| 1. |
- Dimkovski, Zlate, et al.
(författare)
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Interference Measurements of Deposits on Cylinder Liner Surfaces
- 2011
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Ingår i: Wear. - Amsterdam : Elsevier. - 0043-1648 .- 1873-2577. ; 270:3-4, s. 247-251
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Tidskriftsartikel (refereegranskat)abstract
- The accumulation of deposits in the honing grooves of the cylinder liner surfaces of internal combustion engines is undesirable as they seal the grooves (reducing their oil retention capability) and increase engine's oil consumption. As part of a long-term programme of truck engine development, after different running times and under similar conditions of load, engine speed and lubrication, a number of grey iron cylinder liners were axially sectioned, measured, inspected and a presence of deposits was discovered. These deposits were characterised in order to gain knowledge about their origin and quantities. The X-ray energy dispersive analysis revealed elements stemming from the oil/fuel (C, O and S), from the detergent (Ca and Mg), from the anti-wear additive (Zn and P), and from some contaminants (K and Si). Higher concentration of S and Ca were mostly found in the honing grooves covered with deposits suggesting a domination of the detergent additive. Deposit thickness measurements obtained by a white light interferometer revealed patchy deposit topographies concentrated at the top region reducing towards the bottom of the liner which was also confirmed by scanning electron microscope measurements. Despite the limitations of the interferometer, it has been shown that the interference measurements are sufficiently reliable for a quick and objective quantification of the overall deposit accumulation.
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| 2. |
- Flys, Olena, 1971-, et al.
(författare)
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Piston ring topography variation and robust characterization
- 2014
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Konferensbidrag (refereegranskat)abstract
- It is a constant challenge for the automotive industry to reduce friction losses and oil consumption in automobile engine. The piston ring friction accounts for approximately 20% of the total mechanical energy losses in a modern engine. Oil control rings limit and control the oil consumption of the engine as well. They scrape off excess lubricating oil from the cylinder walls and return it to the crank case. Piston rings are designed to distribute the thin oil film evenly to ensure piston and ring lubrication. The surface topography of a piston ring is an efficient variable in the control of the oil consumption and friction losses. In places where the interacting surfaces come in contact, the oil film thickness is extremely thin and the surface asperities may deform because of the high pressures. There are different types of oil control rings.The most common one is the twin land oil control ring, which consists of two narrow lands that scrape off the oil on the liner and a spring on the back that exerts the load. In this paper, the surfaces of the two lands were investigated, since they play the key role in its function. The goal is to map the variation in surface roughness of piston rings that appear at different scales from form and waviness to micro and nano roughness. Areal topography measurements were made by white light interferometer designed at the Halmstad University able to measure and scan the total functional area of a piston ring. An significant amount of oil control piston rings of heavy duty truck engines were examined and 24 measurements were made in circumferential direction and on each ring land. The results show both the variation and uncertainty of the ring topography and discuss the instrument and measuring methodology uncertainty. The most stable parameters were found and recommended for an effective quality control. Comparisons between established coherence scanning interferometer and the instrument built in Halmstad were made. To ensure a good quality, the measurements were made both on calibration standards and on piston ring surfaces. Finally the influence on function and energy losses in the final engine assembly is discussed to indicate future design and metrology improvements.
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| 3. |
- Rosén, Bengt Göran, 1962-, et al.
(författare)
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Analysis of 3-D surfaces in forming dies and sheet metal - Today and tomorrow
- 2004
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Ingår i: Proceedings of the International Conference on Recent Advances in Manufacture and Use of Tools and Dies and Stamping of Steel Sheets. ; , s. 29-53
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Konferensbidrag (refereegranskat)abstract
- The effects of surface roughness on production of steel sheet are critically reviewed. New developments in the measurement and characterisation of surface roughness seem likely to improve our understanding of its effect on sheet metal production. Much useful information can still be acquired by 2D techniques but increasingly the evidence is that sheet metal surface roughness is better measured and characterised by 3D methods. The facility for direct surface visualization in 3D is shown to be particularly helpful. When measuring 3D the measurement area size and sampling space are critical and for evaluation the filtering of surface data into roughness and waviness is more complicated than for 2D profiles.
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| 4. |
- Rosen, Bengt-Göran, 1962, et al.
(författare)
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Topographic modelling of haptic properties of tissue products
- 2014
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Ingår i: Journal of Physics: Conference Series. - Bristol : IOP Publishing. - 1742-6588 .- 1742-6596. ; 483:1
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Konferensbidrag (refereegranskat)abstract
- The way a product or material feels when touched, haptics, has been shown to be a property that plays an important role when consumers determine the quality of products For tissue products in constant touch with the skin, softness becomes a primary quality parameter. In the present work, the relationship between topography and the feeling of the surface has been investigated for commercial tissues with varying degree of texture from the low textured crepe tissue to the highly textured embossed- and air-dried tissue products. A trained sensory panel at was used to grade perceived haptic «roughness». The technique used to characterize the topography was Digital light projection (DLP) technique, By the use of multivariate statistics, strong correlations between perceived roughness and topography were found with predictability of above 90 percent even though highly textured products were included. Characterization was made using areal ISO 25178-2 topography parameters in combination with non-contacting topography measurement. The best prediction ability was obtained when combining haptic properties with the topography parameters auto-correlation length (Sal), peak material volume (Vmp), core roughness depth (Sk) and the maximum height of the surface (Sz). © Published under licence by IOP Publishing Ltd.
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| 5. |
- Rosén, Bengt Göran, et al.
(författare)
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Topographical characterisation of artificial femoral heads : a Benchmarking study
- 2004
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Ingår i: Wear. - : Elsevier. - 0043-1648 .- 1873-2577. ; 257:12, s. 1275-1280
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Tidskriftsartikel (refereegranskat)abstract
- The main functional demands on artificial joints are that they last more than 20 years. This means optimising the friction coefficient to minimise forces transmitted to the surrounding bone and the wear of the contacting surfaces. Surface roughness has an important influence on friction and wear. Traditionally, the 2D Ra-parameter has been the preferred way to characterise the joint's topography. Today ongoing development of 3D techniques are available for the research, and the aim of the present paper is to highlight the importance and possibilities using high-resolution 3D atomic force microscope ( AFM) and the optical phase-shifting interferometer for texture characterisation of eight commercially available femoral heads. The results show a significant variation of topography and surface-lay for the different femoral heads in the study. The variation and difference between heads were further underlined by the use of different characterisation techniques and measuring strategy. Results highlight the importance of the selection of measurement strategy, parameters, instrumentation, and scale of measurement in order properly to characterise the femoral heads in this study.
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| 6. |
- Rosén, Stefan, et al.
(författare)
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The Stedman diagram revisited
- 2014
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Ingår i: Surface Topography : Metrology and Properties. - Bristol : Institute of Physics (IOP). - 2051-672X. ; 2:1
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Tidskriftsartikel (refereegranskat)abstract
- The Stedman diagram has been used for some years to display aspects of the performance of instruments measuring surface roughness. Such diagrams are herein employed to compare the features of a range of proprietary measuring instruments, including contact and non-contact devices. An extension of the basic diagram is proposed, which would allow it to include a further aspect: the speed of data collection. Figures of merit based on the revised diagram are computed, which enable instruments to be ranked on these particular aspects of their performance. Contact instruments emerge as comparable to non-contact, as their slower rate of data acquisition can be offset by the greater area they can access in amplitude–wavelength space. © 2014 IOP Publishing Ltd.
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| 7. |
- Rosén, Stefan, et al.
(författare)
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The Stedman diagram revisited
- 2013
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Ingår i: Metrology and Properties of Engineering Surfaces, 2013. ; , s. 201-206
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Konferensbidrag (refereegranskat)abstract
- The Stedman diagram has been used for some years to display aspects of the performance of surface roughness measuring instruments. Such diagrams are herein employed to compare the features of a range of proprietary measuring instruments, including contact and non-contact devices. An extension of the basic diagram is proposed which would allow it to include a further aspect, speed of data collection. Figures of merit based on the revised diagram are computed which enable instruments to be ranked on these particular aspects of their performance. Contact instruments emerge as comparable to non-contact, as their slower rate of data acquisition can be offset by the greater area they can access in amplitude-wavelength space.
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| 8. |
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| 9. |
- Anderberg, Cecilia, et al.
(författare)
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Alternative descriptions of roughness for cylinder liner production
- 2009
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Ingår i: Journal of Materials Processing Technology. - Amsterdam : Elsevier. - 0924-0136 .- 1873-4774. ; 209:4, s. 1936-1942
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Tidskriftsartikel (refereegranskat)abstract
- The roughness of stratified surfaces such as cylinder liners, produced by plateau honing, is functionally important in their tribology but is notoriously difficult to characterise. An issue in manufacturing quality control related to their tribological function is the comparative ability of various roughness characterisation systems. In this paper the Rk family of parameters is compared with the Rq family as regards stability and discrimination. When coefficients of variation of the two parameter families are compared as a measure of stability, CVs of individual parameters vary between 8% and 20% but do not seem to indicate a clear advantage to either family. When the correlation of parameters within and between the two groups is computed as a measure of relative discriminative ability, many parameters are found to be highly correlated, to the point where values of Rpk and Rpq are effectively indistinguishable. The relative robustness of the parameters is also established by simulation of surface or measurement artefacts: outlying peaks and valleys, high-frequency noise, changes in stylus or skid radius, changes in high-pass filter and in assessment length. Outlying peaks cause a large increase in Rpk, while outlying valleys have little effect. The Rq parameters are more sensitive to high-frequency noise than the Rk parameters. Increasing the stylus radius reduced the valley parameters, while adding a 25 mm radius skid increased Rk and Rpq by as much as 15%. Increasing the short-wavelength cut-off from 2.5 m to 8 m reduced most parameters, particularly the peak parameters, while replacing the robust Gaussian filter used throughout by a valley-suppression filter had little effect. Finally reducing the assessment length from 17 mm to 4 mm decreased the values of many parameters by up to 11%. Increasing plateau honing time decreased plateau roughness, while increasing pressure during coarse honing increased valley roughness, but these changes could not be correlated with roughness parameters. This suggests that the optimum parameter set has not yet been found. 2008 Elsevier B.V. All rights reserved.
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| 10. |
- Anderberg, Cecilia, et al.
(författare)
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Combined SEM and Stylus Profiling Sensoring for Improved Cylinder Liner Honing
- 2006
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Ingår i: Proceedings of Austrib 06 - International Tribology Conference. - Brisbane : Queensland University of Technology. ; , s. 6-
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Konferensbidrag (refereegranskat)abstract
- The demands on decreased environmental impact from vehicles are resulting in a strong push for decreased engine oil and fuel consumption.Recent engine tests have shown a promising reduction in oil consumption when using cylinder liners with a smoother finish than the current plateau honing.One approach to produce smoother liner surfaces is to replace SiC ceramic honing stones with diamond tools. However, even though the diamond honing process results in higher productivity, improved quality control is needed to monitor the degree of cold worked material - “blechmantel” (German), and the resulting risk of increased wear and scuffing.A number of petrol and diesel engine cylinder liners have been mapped to be able to verify the quality and consequences, in terms of wear and function, of the honing process. A new mapping method, combining SEM images and quantitative image analysis with traditional 2D profilometry has been developed and tested in this study. The surface mapping method developed was employed before and after the test to study effect of running-in wear on the surface, features characterized with the SEM- and the 2D profilometer.The results show that combining SEM- and profilometric methods gives a good picture of the effects of varying the cylinder liner pressure and roughness. The core roughness decreases more for diesel liners than for petrol liners.. A probable cause is that the more severe diesel high pressure run-in conditions are able to effectively “truncate” the plateaux and remove residing plastically deformed un-cut honing residues while the less severe petrol liner conditions do not manage to remove the blechmantel and irregularities to an important extent.
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| 11. |
- Anderberg, Cecilia, et al.
(författare)
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Cylinder Liners and Consequences of Improved Honing
- 2006
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Ingår i: Proceedings of Nordtrib conference 2006, Helsingor, Danemark. ; , s. 13-
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Konferensbidrag (refereegranskat)abstract
- The demands on decreased environmental impact from vehicles are resulting in a strong push for decreased engine oil and fuel consumption. Engine oil and fuel consumption are to a great extent controlled by the topography of the cylinder liner surface.Recent engine tests have shown a promising reduction in oil consumption when using cylinder liners with a smoother finish than the current plateau honing.One approach to produce smoother liner surfaces is to replace SiC ceramic honing stones with diamond tools. However, event though the diamond honing process results in higher productivity, improved demands of quality control is needed to monitor the degree of cold worked material - “blechmantel” (German), and the resulting risk of increased wear and scuffing.A number of petrol and diesel engine cylinder liners have been mapped to be able to verify the quality and consequences, in terms of wear and function, of the honing process. A new mapping method, combining SEM images and quantitative image analysis with traditional 2D profilometry has been developed and tested in this study. The liners where tested in a reciprocating rig of 8 mm stroke and with a frequency of 10 Hz, simulating the top-dead center conditions in a running engine.The tests where carried out in high- and low pressure conditions with smooth respectively rough liner roughnesses against PVD coated piston rings. The developed surface mapping method was employed before and after the test to study effect of running-in wear on the surface, features characterized with the SEM- and the 2D profilometer.The results show that combining SEM- and profilometric methods gives a good picture of the effects of varying the cylinder liner pressure and roughness. The core roughness decrease more for diesel liners than for petrol liners. In average (rough and smooth liners) the diesel core roughness decrease 265% while the petrol liners average on a 60% decrease. Blechmantel- and Irregularities ratio show a high sensitivity to varying conditions and decrease 1180% to 100% for the diesel liners while the parameters increase between 106% to 18% for all the petrol liners. A probable cause is the more severe diesel high pressure run-in conditions are able to effectively “truncate” the plateaux and remove residing plastically deformed un-cut honing residues while the less severe petrol liner conditions not manage to remove the blechmantel and irregularities in an important extent.
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| 12. |
- Anderberg, Cecilia, 1963-, et al.
(författare)
-
Liner surface improvements for low friction piston ring packs
- 2014
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Ingår i: Surface Topography : Metrology and Properties. - Bristol : Institute of Physics (IOP). - 2051-672X. ; 2:1
-
Tidskriftsartikel (refereegranskat)abstract
- The development of engine components in the automotive industry is governed by several constraints such as environmental legislation and customer expectations. About a half of the frictional losses in an internal combustion engine come from the interactions between the piston assembly and cylinder liner surface. The tribological considerations in the contact between the piston ring and cylinder liner have attracted much attention over the past few decades. Many non-conventional cylinder liner finishes have been, and are being, developed with the aim to reduce friction losses and oil consumption, but the effects of the surface finish on piston ring pack performance is not well understood. One way of reducing friction in the cylinder system is to reduce the tangential load from the piston ring pack, focusing on the oil control ring. However, the side-effect of this is a disappointingly increased oil consumption. In this study a number of different cylinder liner surface specifications were developed and implemented in test engines with the aim of maintaining the level for oil consumption when decreasing the tangential load for the piston ring pack. To improve our understanding of the result, the same surfaces were evaluated in elastic and elasto-plastic rough contact and hydrodynamic flow simulation models. It is shown that oil consumption is strongly related to surface texture on the cylinder liners and at lower speeds (900–1200 rpm), a 'rougher surface' with a high core (e.g. Sk) and valley roughness (e.g. Svk) results in higher oil consumption. At the medium speed range (1200–3600 rpm), oil consumption continues to dominate for the 'rough' surfaces but with a visible influence of a lower oil consumption for a decreased roughness within the 'rough' surface group. 'Smooth' surfaces with a 'smooth' core (Sk), irrespective of the valley component (Svk), show similar oil consumption. For engine speeds above 3600 rpms, an increase in plateau roughness results in higher oil consumption. Throughout the study, standard roughness parameters were computed to compare with the results from engine testing and simulation. Future work will be directed to continuous optimization between oil consumption and friction. Improving the understanding of the functional cylinder system surfaces' ability to form oil films in the cylinder system opens up opportunities, not only in reducing the tangential load of piston ring packs but also in optimizing oil viscosity in order to reduce friction.
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| 13. |
- Anderberg, Cecilia, et al.
(författare)
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Liner Surface Improvements for Low Friction Piston Ring Packs
- 2009
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Ingår i: Society of Tribologists and Lubrication Engineers annual meeting & exhibition 2009. - Red Hook, NY : Curran Associates, Inc.. - 9781615674374 ; , s. 455-459
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Konferensbidrag (refereegranskat)
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| 14. |
- Anderberg, Cecilia, et al.
(författare)
-
Low friction and emission cylinder liner surfaces and the influence of surface topography and scale
- 2019
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Ingår i: Tribology International. - Kidlington : Pergamon Press. - 0301-679X .- 1879-2464. ; 133, s. 224-229
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Tidskriftsartikel (refereegranskat)abstract
- A low friction piston ring pack, with tangential load halved, was tested in engines with four different cylinder liner finishes. Oil consumption, oil temperature and liner surface temperature were monitored at different load and speed levels, under similar test conditions. The two smoother surfaces generally kept lower oil consumption compared to the two rougher ones. Results were correlated using an area-fractal analysis. The relative area of the surface was calculated at different scales and the result was compared with the level of oil consumption for the different liner surfaces at different engine speeds. It was found that oil consumption was strongly correlated with scale for areas of above 1000 μm2 and below 20 μm2. © 2018
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| 15. |
- Anderberg, Cecilia, et al.
(författare)
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Wear Resistance of Smooth Automotive Cylinder Liner Surfaces
- 2005
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Ingår i: World Tribology Congress III, Volume 2. - New York, NY : ASME Press. - 0791842029 ; , s. 603-604
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Konferensbidrag (refereegranskat)abstract
- Demands for decreased environmental impact from vehicles are resulting in a strong push for decreased engine oil, fuel consumption and weight. New machining and coating technologies have offered ways to attack these problems. Engine oil and fuel consumption are to a great extent controlled by the topography of the cylinder liner surface and it is therefore important to optimise this surface. Recent engine tests have shown a reduction in oil consumption when using cylinder liners with a smoother finish than that given by the current plateau honing. However, engine manufacturers are hesitant to introduce smoother liner surfaces because of fears of severe wear and scuffing. There is also the possibility that smoother liner surfaces may be more sensitive to the choice of piston ring finishes. This paper therefore seeks to investigate the functional performance and resistance to wear of these smooth cylinder liners and the mating top ring surfaces. Copyright © 2005 by ASME
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| 16. |
- Andersson, Martin
(författare)
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An experimental investigation of spur gear efficiency and temperature : A comparison between ground and superfinished surfaces
- 2017
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- This thesis focuses on reliability when testing gear efficiency and on how gear mesh efficiency can be increased without detrimental effects on the gears. Test equipment commonly used in gear research was analysed to identify important parameters for gear efficiency testing. The effect of the bearing model's load-dependent losses on gear mesh efficiency was also investigated. Two different surface finishes of gears, ground and superfinished, were investigated to determine how two different load levels during running-in affect gear mesh efficiency and changes in surface roughness. Efficiency and gear temperature were also measured for ground and superfinished gears with dip lubrication, as well as two different forms of spray lubrication (before and after gear mesh contact).Tests on a gear test rig, showed that different assemblies of the same test setup can yield different measurements of torque loss. The applied bearing model had a significant effect on the estimated gear mesh efficiency. The mesh efficiency of ground gears is affected by the running-in procedure, with a higher running-in load resulting in a higher mesh efficiency than a lower load. This effect was not seen for superfinished gears, which show the same gear mesh efficiency for both running-in loads. Gearbox efficiency increased with spray lubrication rather than dip lubrication. The gear mesh efficiency increased, and thus gear temperatures were reduced, when superfinished gears were used rather than ground gears. A lower gear temperature was measured when gears were spray lubricated at the mesh inlet rather than the mesh outlet.
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| 17. |
- Barth, Henrik, 1971-, et al.
(författare)
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From Traditional Manufacturing to Digital Manufacturing : Two Swedish Case Studies
- 2023
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Ingår i: Innovation - Research and Development for Human, Economic and Institutional Growth. - Rijeka : InTech. - 9781837689965 - 9781837689972 - 9781837689989
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Bokkapitel (refereegranskat)abstract
- Digital manufacturing can produce new and advanced tools more rapidly and at lower cost than traditional manufacturing. This new technology means manufacturers need to develop innovative business models adapted to this change in the manufacturing landscape. With digital manufacturing, companies have both an opportunity and a challenge. They can enter new markets where large-scale production provides competitive advantage. They can enter niche markets that become more attractive as old boundaries and structures lose relevance. Yet their additive manufactured components must meet the same standards set for conventional manufactured components. However, we know little about how companies manage this change as they make the transition from traditional manufacturing to digital manufacturing. This chapter presents two co-creation digital manufacturing projects between university researchers and Swedish companies. In each project, the goal was to develop sustainable and efficient digital production methods that offer tailor-made product solutions. Various technical methods used in the projects are described as materials, and prototypes are developed, tested, and analyzed.
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| 18. |
- Barth, Henrik, 1971-, et al.
(författare)
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The use and abuse of 3D-printing from a business model perspective
- 2016
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Konferensbidrag (refereegranskat)abstract
- The paper analyses changes in user activities and behaviour across different types of actors following the introduction of 3D printers. 3D printing, or additive manufacturing, has been claimed to disrupt manufacturing, allowing firms to move from prototyping to full-scale end-part production and replacement part production in a one-step process. 3D printing has many different uses, for example, the manufacturing of toys, shoes, lamps and fashion accessories, and by implication many different types of users and buyers. There are few empirical studies on the types of uses and users of 3D, hampering our understanding in what ways the 3D printers may change the behaviour of users, and whether 3D printers affect the likelihood and the nature of entrepreneurship or business model innovation. To investigate this, a model was created based on the 3DP literature. The model is applied on a distributor customer database and four interview-based illustrative case studies. The empirical findings show that the use of 3DP a) lowers the knowledge and resource barriers for experimentation and entrepreneurial entry, b) increases product and concept prototyping in product development, c) provides a potential for business model innovation by expanding the boundaries of the firm upstream and downstream, and d) becomes a ticket for entrepreneurial entry. Based on our results, the paper suggests that the potential of 3D printers alter user innovative activities is high but most of the potential is latent.
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| 19. |
- Barth, Henrik, 1971-, et al.
(författare)
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The use and abuse of 3D printing - Towards a mobile business model framework
- 2019
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Ingår i: International Journal of Engineering Research and Applications. - Ghaziabad : International Journal of Engineering Research and Applications. - 2248-9622. ; 9:11, s. 1-9
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Tidskriftsartikel (refereegranskat)abstract
- The paper aim to clarify changes in user activities and behaviour across different types of actors following the development of 3D printers. It proposes a mobile business model and outlining the features of development for direct digital manufacturing.The exploratory study show that the use of 3D printing a) lowers the knowledge and resource barriers for experimentation and entrepreneurial entry, b) increases product and concept prototyping in product development, c) provides a potential for business model innovation by expanding the boundaries of the firm upstream and downstream, and d) becomes a ticket for entrepreneurial entry
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| 20. |
- Berglund, Johan C, 1978, et al.
(författare)
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A method development for correlation of surface finish appearance of die surfaces and roughness measurement data
- 2009
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Ingår i: Tribology letters. - Berlin : Springer Berlin/Heidelberg. - 1023-8883 .- 1573-2711. ; 36:2, s. 157-164
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Tidskriftsartikel (refereegranskat)abstract
- In die and mould manufacturing, the method used for quality control of finished surfaces is usually visual and tactile inspection of the finish, which is not easily quantifiable. In the present study, an evaluation of the connection between surface finish appearance and measured surface roughness was carried out using scale-sensitive fractal analysis to find functional correlations and to determine suitable cut-off limits for functional data filtration. A selection of ball-nose end-mills in combination with two different tool steels (hardness 39 and 47 HRC) were used to manufacture surfaces that were inspected and measured. It was found that the method developed in the present study for evaluating functional correlations and designing filters worked well. It was also found that there is a correlation between the surface roughness parameter Sq and the surface finish appearance and that this correlation is stronger in certain wavelengths on the surface.
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| 21. |
- Berglund, Johan C, 1978, et al.
(författare)
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A Method for Visualization of Surface Texture Anisotropy in Different Scales of Observation
- 2011
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Ingår i: Scanning. - : John Wiley & Sons. - 0161-0457 .- 1932-8745. ; 33:5, s. 325-331
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Tidskriftsartikel (refereegranskat)abstract
- Anisotropy of functional surfaces can in many practical cases significantly influence the surface function. Tribological contacts in sheet forming and engine applications are good examples. This article introduces and exemplifies a method for visualization of anisotropy. In a single graph, surface texture properties related to the anisotropy as a function of scale are plotted. The anisotropy graph can be used to explain anisotropy properties of a studied surface such as texture direction and texture strength at different scales of observation. Examples of milled steel surfaces and a textured steel sheet surface are presented to support the proposed methodology. Different aspects of the studied surfaces could clearly be seen at different scales. Future steps to improve filtering techniques and an introduction of length-scale analysis are discussed.
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| 22. |
- Berglund, Johan C, 1978, et al.
(författare)
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Machine Hammer Peening – A Substitute for Polishing of Pressing Die Surfaces?
- 2009
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Ingår i: Proceedings of the International 3'rd Swedish Production Symposium. - 9789163360060 ; :Day 1, s. 184-189
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Konferensbidrag (refereegranskat)abstract
- Machine Hammer Peening (MHP) is a new method for finishing of surfaces. With this method the workpiece surface is hammered with a spherical carbide tool. The main objective of the study was to evaluate whether the MHP method could be used as a plausible substitute for manual polishing in pressing die manufacturing. To do this, sample surfaces were hammered and evaluated. Changes to the surfaces were assessed using surface roughness measurements, hardness measurements and optical images. First of all, the workpiece surface was smoothened. Secondly, the surface hardness was increased significantly. Thirdly, the nodules on the workpiece surface were effected. They appeared to be smaller and not as visible. It is probable that they had been plastically deformed and that some of the graphite in the nodules was replaced by material from the surrounding steel matrix. By replacing the graphite in the larger nodule cavities by surrounding steel material, a die surface is created which would be less prone to galling. In addition, with MHP, the amount of polishing needed to manufacture a die surface can be reduced because of the smoothening effect.
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| 23. |
- Berglund, Johan C, 1978, et al.
(författare)
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Measuring strategies for smooth tool steel surfaces
- 2008
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Ingår i: Proceedings. - Aachen : Shaker Verlag. - 1610-4773. - 9783832269128 - 3832269126 ; , s. 110-119
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Comparisons between different measuring strategies were made on three types of smooth tool steel surfaces. Three replica materials were tested to study possibilities within replication techniques. An optical interferometer as well as a mechanical stylus was used to evaluate the surfaces. The results showed that the tested replica materials generated good representations of both the form and the surface roughness (Sq > 300 nm). The evaluated surfaces were quite homogeneous, thus, few measurements are needed to get representative results. However, it was found that caution must be taken regarding manually polished surfaces which can be less homogenous and therefore require more measurements to get representative results.
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| 24. |
- Berglund, Johan C, 1978, et al.
(författare)
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Milled die steel surface roughness correlation with steel sheet friction
- 2010
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Ingår i: CIRP Annals - Manufacturing Technology. - Bern : Elsevier BV. - 1726-0604 .- 0007-8506. ; 59:1, s. 577-580
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Konferensbidrag (refereegranskat)abstract
- This work investigates correlations between the surface topography of milled steel dies and friction with steel sheet. Several die surfaces were prepared by milling. Friction was measured in bending under tension testing. Linear regression coefficients (R^2) between the friction and texture characterization parameters were tested. None of the height, spacing, material volume, void or segmentation parameters showed good correlations. Developed area, rms surface gradient, relative area and complexity showed strong correlations (R^2 > 0.7). For area-scale fractal complexity the correlation increases markedly at scales below 200 μm^2, with a maximum R^2 of 0.9 at 50 μm^2.
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| 25. |
- Berglund, Johan C, 1978, et al.
(författare)
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On discovering relevant scales in surface roughness measurement : an evaluation of a band-pass method
- 2010
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Ingår i: Scanning. - London : John Wiley & Sons. - 0161-0457 .- 1932-8745. ; 32:4, s. 244-249
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Tidskriftsartikel (refereegranskat)abstract
- When characterizing surfaces and searching for correlations to functional properties, such as friction, finding the right scale of roughness for evaluation can improve correlations. However, in traditional roughness parameter analysis, a wide range of scales, or all scales of topography in the surface roughness measurements are evaluated together. In this study a multi-scale method using a series of band-pass filters is employed for finding scales of topography with strong correlations to friction.
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| 26. |
- Berglund, Johan C, 1978, et al.
(författare)
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On finishing of pressing die surfaces using machine hammer peening
- 2011
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Ingår i: The International Journal of Advanced Manufacturing Technology. - Berlin : Springer Berlin/Heidelberg. - 0268-3768 .- 1433-3015. ; 52:1-4, s. 115-121
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Tidskriftsartikel (refereegranskat)abstract
- Machine hammer peening (MHP) is a new method for finishing of surfaces. With this method, the workpiece surface is hammered with a spherical carbide tool. The main objective of the study was to evaluate whether the MHP method could become a plausible substitute for manual polishing in pressing die manufacturing where nodular cast iron is a common workpiece material. To do this, sample nodular cast iron surfaces were hammered and evaluated. Changes to the surfaces were evaluated using surface roughness measurements, hardness measurements and optical images. First of all, the workpiece surface was smoothened. Secondly, the surface hardness was increased significantly. Thirdly, the nodules on the workpiece surface were affected. They appeared to be smaller and not as visible. This effect would likely create a die surface less prone to galling since the cavities would not be filled with sheet metal to the same extent in a forming operation. In addition, with MHP, the amount of polishing needed to manufacture a die surface can be reduced because of the smoothening effect.
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| 27. |
- Berglund, Johan C, 1978, et al.
(författare)
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Robust and Easy to Use Quality Control of Roughness on Milled Tool Steel Surfaces
- 2008
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Ingår i: Proceedings of the 18th International Conference on Flexible Automation and Intelligent Manufacturing. - 9789163327575 ; , s. 284-289
-
Konferensbidrag (refereegranskat)abstract
- This study was an evaluation of measuring strategies using a handheld 2D profiler for quality control of finish milled tool steel with regard to surface roughness. A selection of ball nose end mills in combination with two different tool steels (hardness 39 and 47 HRC) were used to manufacture the surfaces that were to be measured. It was found that using an appropriate measuring strategy it is possible to measure the roughness of these relatively smooth surfaces (0.1
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| 28. |
- Berglund, Johan C, 1978, et al.
(författare)
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Surface Finish and Roughness Measurement in Die and Mould Manufacturing
- 2008
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Ingår i: Proceedings of the 2'nd Swedish Production Symposium. ; , s. 385-391
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Konferensbidrag (refereegranskat)abstract
- In die and mould manufacturing, the method used for quality control of finished surfaces is usually visual and tactile inspection of the finish, which is not easily quantifiable. In this study, an evaluation of the connection between surface finish appearance and measured surface roughness was carried out using scale-sensitive fractal analysis to find functional correlations and to determine suitable cut-off limits for functional data filtration. A selection of ball nose end mills in combination with two different tool steels (hardness 39 and 47 HRC) were used to manufacture surfaces that were measured. It was found that the method employed in this study for evaluating functional correlations and designing filters worked well. It was also found that there is a correlation between the surface roughness parameter Sq and the surface finish appearance and that this correlation is stronger in certain wavelengths on the surface.
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| 29. |
- Berglund, Johan, et al.
(författare)
-
Robust and Easy to Use Quality Control of Roughness on Milled Tool Steel Surfaces
- 2008
-
Ingår i: Proceedings of the 18th International Conference on Flexible Automation and Intelligent Manufacturing. - Skövde : Skövde University. - 9789163327575 ; , s. 284-289
-
Konferensbidrag (refereegranskat)abstract
- This study was an evaluation of measuring strategies using a handheld 2D profiler for quality control of finish milled tool steel with regard to surface roughness. A selection of ball nose end mills in combination with two different tool steels (hardness 39 and 47 HRC) were used to manufacture the surfaces that were to be measured. It was found that using an appropriate measuring strategy it is possible to measure the roughness of these relatively smooth surfaces (0.1<1µm) with satisfactory accuracy using a handheld profiler. However, it was also found that, in contrast to what is common practice, Ra is not a suitable parameter to use for evaluation. Instead, using Rz or Rp is suggested. To be able to control quality, the machining process (selection of cutting tool, cutting data, workpiece material etc) as well as limits for the evaluated parameters first have to be established.
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| 30. |
- Bergman, Martin, 1985-, et al.
(författare)
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Material & Surface design methodology-the user study framework
- 2020
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Ingår i: Surface Topography-Metrology and Properties. - Bristol : Institute of Physics Publishing (IOPP). - 2051-672X. ; 8:4
-
Tidskriftsartikel (refereegranskat)abstract
- A material and surface selection within the car industry is usually based on a comprehensive study based on sensation and perception, focusing on particular perceived qualities and impressions (emotional functions) through visual and tactile interaction of plastic surfaces. On top of that 'emotional function', the 'technical function' such as surface roughness or gloss for a certain matter in symbiosis, will result in a number of material and surface proposals. The range of materials fitting into the window of these requirements varies depending on the industry's ability to hit the target specified in regard to the 'emotional functions', usually defined by the designer's intention. Thus, to be able to get a deeper understanding of how to frame the 'emotional functions' and link them to the 'technical functions', two user studies were made in this paper. The user studies were made with two different designs however with the same main research target to be able to understand the varieties of these two. The aim of doing so was to be able to find the user study design that was the most time efficient and providing the most significant data linked to the 'technical functions' and process control/traceability. However also finding the user study design with the least strains for the participating users in regard to uninterrupted brain activity. By designing the user study in relevant subsets in a certain sequence, user study design nr 2 has proven to be more time efficient and provide more data regarding the soft metrology. Future work will focus on deeper knowledge about how these surfaces different material- and surface properties correlate to the participants responses regarding perceived quality of a car interior design. The development of a new non-contact measurement is also discussed, enabling the possibility to complement and improve the hard metrology set up.
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| 31. |
- Bergman, Martin, 1985-, et al.
(författare)
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Surface appearance and impression
- 2012
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Ingår i: Proceedings of the International Conference on Kansei Engineering and Emotion Research. - Tainan : Department of Industrial Design, National Cheng Kung University. - 9789860324884
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Konferensbidrag (refereegranskat)
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| 32. |
- Bergman, Martin, 1985-, et al.
(författare)
-
Surface design methodology : challenge the steel
- 2013
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Ingår i: Metrology and Properties of Engineering Surfaces, 2013. - Bristol, UK : Institute of Physics Publishing (IOPP). ; 483:1, s. Art. no. 012013-
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Konferensbidrag (refereegranskat)abstract
- The way a product or material is experienced by its user could be different depending on the scenario. It is also well known that different materials and surfaces are used for different purposes. When optimizing materials and surface roughness for a certain something with the intention to improve a product, it is important to obtain not only the physical requirements, but also the user experience and expectations. Laws and requirements of the materials and the surface function, but also the conservative way of thinking about materials and colours characterize the design of medical equipment. The purpose of this paper is to link the technical- and customer requirements of current materials and surface textures in medical environments. By focusing on parts of the theory of Kansei Engineering, improvements of the companys' products are possible. The idea is to find correlations between desired experience or «feeling» for a product, -customer requirements, functional requirements, and product geometrical properties -design parameters, to be implemented on new improved products. To be able to find new materials with the same (or better) technical requirements but a higher level of user stimulation, the current material (stainless steel) and its surface (brushed textures) was used as a reference. The usage of focus groups of experts at the manufacturer lead to a selection of twelve possible new materials for investigation in the project. In collaboration with the topical company for this project, three new materials that fulfil the requirements -easy to clean and anti-bacterial came to be in focus for further investigation in regard to a new design of a washer-disinfector for medical equipment using the Kansei based Clean ability approach CAA. © Published under licence by IOP Publishing Ltd.
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| 33. |
- Bergstedt, Edwin, 1986-
(författare)
-
A Comparative Investigation of Gear Performance BetweenWrought and Sintered Powder Metallurgical Steel : Utilizing In-situ Surface Profile Measurements to Investigate theInitiation and Evolution of Micropitting and Pitting Damage
- 2021
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Vehicle electrification is a strong trend that introduces new challenges, such as increased input speed of the transmission and increased power density. Alsothe noise emittance of the gearbox is of increasing importance, as the sound of the gearbox is no longer masked by the internal combustion engine. Pressed and sintered powder metallurgical steel could be an interesting alternative towrought steel; the internal porosity has a dampening effect on the noise, and gears can be made in a fast and efficient process. However, current manufacturing of powder metallurgical steel has significant performance limitations. The Nanotechnology Enhanced Sintered Steel Processing project aims to reduce the gap in performance between conventional steel and powder metallurgical steel. One of the potential benefits is that with the inclusion of nano-powder the density can be increased. To validate the new material, its performance needs to be compared to the performance of current generation powder metallurgical materials and also to wrought steel. It is therefor crucial to be able to test and evaluate different materials and gears. This thesis has developed methods for testing, comparing, and evaluating the performance of gears. Powder metallurgical steel has been tested and compared to wrought steel; the efficiency as well as pitting life have been investigated in an FZG test rig. Also the effects of different surface finishing operations have been evaluated. The gear flanks were measured in-situ in the gearbox using a stylus instrument; an optimisation routine was created to fit the measurements to the theoretical involute profile. This enabled an in-depth analysis of surface wear and presented an opportunity to investigate micropitting initiation. It was found that the damage mechanisms of wrought steel and powder metallurgical steel are similar and related to the surface finishing method. However, the powder metallurgical steel was also susceptible to sub-surface cracks. Superfinished gears can be negatively influenced by the lack of tip relief as cracks initiate in the surface layer of the root, rapidly destroying the tooth.
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| 34. |
- Braun, Greta, 1995, et al.
(författare)
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Ingenjör4.0 – A National Upskilling Programme to Bridge Industry’s Skill Gap
- 2023
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Ingår i: Procedia CIRP. - Amsterdam : Elsevier. - 2212-8271. ; 120, s. 1286-1291, s. 1286-1291
-
Konferensbidrag (refereegranskat)abstract
- Manufacturing industry needs major transformation to meet disruptive environmental, social, and economic challenges, thus requiring a highly skilled workforce. This paper presents key functionalities, results, and best-practices for the launch and operation of a national upskilling platform. The Swedish upskilling programme Ingenjör 4.0's operations have been constantly user-monitored through participant surveys measuring appreciation for training content from the participants and identifying areas with potential for improvement. Thematic analysis of 137 survey responses identified dimensions relevant for an upskilling programme's success. Results show that success factors and hurdles typically lie within the following dimensions: relevance, organization and structure, working life competencies, support from teachers, and collaboration with other learners. The paper concludes that national programmes like Ingenjör4.0 can, in a short time, have deep impact on skill levels for manufacturing industries in areas such as industrial digitalization. Highlighted success factors are: participant appreciation of highly relevant content, collaboration with other participants, highly competent teachers, and the collaboration between universities. Obstacles for the learners are feelings of mismatch in challenges and prior knowledge, lack of feedback and applicable working life examples in the teaching, and the need for increased collaboration with other participants.
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| 35. |
- Bruch, Jessica
(författare)
-
Management of Design Information in the Production System Design Process
- 2012
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- For manufacturing companies active on the global market, high-performance production systems that contribute to the growth and competitiveness of the company are essential. Among a wide range of industries it is increasingly acknowledged that superior production system capabilities are crucial for competitive success. However, the process of designing the production system has received little attention, ignoring its potential for gaining a competitive edge. Designing production systems in an effective and efficient manner is advantageous as it supports the possibility to achieve the best possible production system in a shorter time. One way to facilitate the design of the production system is an effective management of design information. Without managing design information effectively in the production system design process the consequences may be devastating including delays, difficulties in production ramp-up, costly rework, and productivity losses.The objective of the research presented in this thesis is to develop knowledge that will contribute to an effective management of design information when designing production systems. The empirical data collection rests on a multiple-case study method and a survey in which the primary data derive from two industrialization projects at a supplier in the automotive industry. Each industrialization project involved the design of a new production system.The findings revealed ten categories of design information to be used throughout the process of designing production systems. The identified design information categories are grouped in the following way: (1) design information that minimizes the risk of sub-optimization; (2) design information that ensures an alignment with the requirements placed by the external context; (3) design information that ensures an alignment with the requirements placed by the internal context, and (4) design information that facilitates advancements in the design work. In order to improve the management of the broad variety of design information required, a framework is developed. The framework confirms the necessity to consider the management of design information as a multidimensional construct consisting of the acquiring, sharing, and using of information. Further, the framework is based on six characteristics that influence the management of design information. These characteristics are information type, source of information, communication medium, formalization, information quality, and pragmatic information. Supported by the findings, guidelines for the management of design information are outlined to facilitate an effective and efficient design of the production system and thus contribute to better production systems. The guidelines are of value to those responsible for or involved in the design of production systems.
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| 36. |
- Bååth, Lars B., et al.
(författare)
-
Surface topography with PDI holography
- 2008
-
Ingår i: Proceedings of the XII. International Colloquium on Surfaces. - Aachen : Shaker Verlag. - 9783832269128 ; , s. 10-
-
Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- This paper presents topographic measurements of metal surface with Point Diffraction Interferometer (PDI) technique. Interferogram of a surface is created and recorded with different phase offsets. These are then combined to create a phase offset map of the surface. We demonstrate the use with the presentation of our first surface topographic map
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| 37. |
- Bååth, Lars, 1948-, et al.
(författare)
-
Towards New Interferometer Technology for Surface Metrology
- 2012
-
Ingår i: Proceedings of the 12th International Conference of the European Society for Precision Engineering and Nanotechnology. - Bedford : EUSPEN. - 9780956679000 ; , s. 158-161
-
Konferensbidrag (refereegranskat)abstract
- There is an increasing requirement from manufacturing industries for improved technologies to measure surface topography. New instruments have to be accurate; robust to be used on the industry floor; non-invasive; automatic; and sufficiently fast to be used in real time as well as to simultaneously measure over a large area. The industrial applications are plenty:On-line quality control of machined parts,Direct feed back to the manufacturing process,Analysis and selection of surface texture/structure.This paper presents new developments in interferometer techniques for new robust area-based topographic instruments.
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| 38. |
- Cabanettes, Frédéric, 1982-
(författare)
-
Cam Roller Contact : The topographical aspect
- 2008
-
Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The automotive industry and the design of engines are strongly ruled by performance and legislation demands. First order aspects defining the main functions of a component are well known and new challenges appear at a lower scale. Wear reduction is defined as a second order problem and requires decreasing the scale of observation of components down to roughness. This thesis work and its aim lie within the scope of wear improvements and are focused on the injection cam/roller contact of heavy duty diesel engines. In order to reach the aim several material and methods are used: a valve train rig test, roughness characterisation and different manufacturing processes. It is shown by experiments that the flank and nose of injection cams are specific areas with specific roughness (higher density of summits Sds) compared to the rest of the cam. The wear is characterized by rounded-off of summits (Ssc). From those results and since wear processes are strongly linked to the pressure generated between the mating surfaces, the development of a rough contact model is of great interest. An elastic rough contact model is implemented and improved later on by an elasto-plastic description of materials. The simulations are validated by a wear test and are used to rank the ability of surfaces (both cam and roller) to face wear problems. The ratio of plastically deformed peaks shows that the flank and nose of the cam are reacting badly to pressures. Additionally the rough contact allows ranking/optimization of different machining processes with respect to their expected functional contact performance. Future work will be to use such a model to choose a good combination of surfaces (cam and roller) in order to reduce wear.
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| 39. |
- Cabanettes, Frédéric, 1982-
(författare)
-
Cam Roller Contact : Surfaces and Tribology
- 2010
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The automotive industry and the design of engines are strongly ruled by performance and legislation demands. In the valve train, mechanical components such as camshafts and rollers are defined by specifications including more and more constraints concerning their ability to face wear thus prolonging lifetime.The aim of the thesis is to develop tools facilitating the choice between different manufacturing processes for wear optimization purposes of cam and roller components for IC engine valve trains. Tools are both experimental and theoretical.For the experimental part, statistical and relocated studies of wear have been performed. It is shown that measuring the very same surface before and after experiments is preferable to understand wear mechanisms of cams and rollers. A set of analysis tools for describing changes between unworn and relocated worn surfaces is developed. As results, it is found that the predominant mechanism of wear for cams and rollers is a flattening of asperities: surfaces are pressed and plastic deformations occur.In parallel, simulations have been developed to explain theoretically the wear observed. Micro and macro simulations are developed to predict the ability of a given manufacturing process to resist wear. For the microscopic simulation, a rough contact model including elasto-plastic behavior of materials is used and shows good correlations with experiments. Concerning the macroscopic simulation, a model including form deviations due to manufacturing is developed and computes oil film thicknesses and deformations. The different parameters computed by both simulations are indicators of the wear performance of different surfaces. It is shown that such simulation can rank different manufacturing processes in terms of ability to face wear.
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| 40. |
- Cabanettes, Frederic, 1982, et al.
(författare)
-
Evaluation of cam and roller surfaces and their manufacturing process by functional characterisation
- 2008
-
Ingår i: Proceedings of the Swedish Production Symposium 2008, Stockholm, Sweden. ; , s. 7-
-
Konferensbidrag (refereegranskat)abstract
- Friction and wear are constant problems encountered in camshaft development. Thecontact between roller and cam is a mix of sliding and rolling which leads to a wide rangeof failure modes. The uniqueness of this contact is also due to variations all around thecam of a multitude of parameters. A previous study described surface topography as afunction of cam shape. The different types of wear mechanisms are strongly linked tocontact pressures which are also dependent on roughness. The aim of the paper is toevaluate the quality of camshafts and rollers produced with different manufacturinghistories. The evaluation utilises standard roughness parameters as well as rough contactparameters. The surfaces measurements are made by a non-contact light interferometerand a set of 3D roughness parameters is evaluated for each measure. The Greenwood-Williamson contact model has been developed and also applied to the measurements inorder to collect characteristics of the microscopic pressures. The results of the study showthe significant effect of topography variations on the tribological behaviour of the camroller contact and rank the different manufacturing processes according to functionalcharacterization. The verification of the ranking using experiments is the continuity of thisstudy.
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| 41. |
- Cabanettes, Frederic, 1982, et al.
(författare)
-
Evaluation of cam and roller surfaces by wear testing and functional characterisation
- 2008
-
Ingår i: Proceedings of the 35th Leeds Lyon Symposium on Tribology. ; , s. 8-
-
Konferensbidrag (refereegranskat)abstract
- Friction and wear are constant problems encountered in camshaft development. The contact between roller and camis a mix of sliding and rolling which leads to a wide range of failure modes. The uniqueness of this contact is also dueto variations all around the cam of a multitude of parameters such as load and radius. A previous study describedsurface topography as a function of cam shape. The different types of wear mechanisms are strongly linked to contactpressures which are also dependent on roughness. The aim of the paper is to develop a rough contact model which willbe utilized as a tool to rank surfaces and their ability to face wear problems. In order to verify the tool, rough contactresults are compared to roughness parameter variations due to wear produced in a cam roller rig test. The surfacemeasurements used for this study are made by a non-contact light interferometer. The Greenwood-Williamson contactmodel has been developed in a deterministic way and the elasto-plastic behaviour of the material has been integratedto the model. The outputs of the simulation give a ranking of surfaces which is compared to their roughness variationsdue to wear. The study shows that the model developed is a reliable tool to rank and define surface quality since theresults are correlated to wear. However, the results show as well some discrepancies which could be corrected in thefuture by integrating to the model two new features: a rough to rough contact including sliding between surfaces. Thisnew model should be verified by an accurate experimentation using relocation between unworn and worn surfaces.
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| 42. |
- Cabanettes, Frédéric, 1982-, et al.
(författare)
-
Evaluation of cam surfaces by wear testing and functional characterization
- 2008
-
Ingår i: Synopses / 35th Leeds-Lyon Symposium on Tribology. - Leeds : Leeds University.
-
Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Friction and wear are constant problems encountered in camshaft development. The contact between roller and cam is a mix of sliding and rolling which leads to a wide range of failure modes. The uniqueness of this contact is also due to variations all around the cam of a multitude of parameters such as load and radius. A previous study described surface topography as a function of cam shape. The different types of wear mechanisms are strongly linked to contact pressures which are also dependent on roughness. The aim of the paper is to develop a rough contact model which will be utilized as a tool to rank surfaces and their ability to face wear problems. In order to verify the tool, rough contact results are compared to roughness parameter variations due to wear produced in a cam roller rig test. The surface measurements used for this study are made by a non-contact light interferometer. The Greenwood-Williamson contact model has been developed in a deterministic way and the elasto-plastic behaviour of the material has been integrated to the model. The outputs of the simulation give a ranking of surfaces which is compared to their roughness variations due to wear. The study shows that the model developed is a reliable tool to rank and define surface quality since the results are correlated to wear. However, the results show as well some discrepancies which could be corrected in the future by integrating to the model two new features: a rough to rough contact including sliding between surfaces. This new model should be verified by an accurate experimentation using relocation between unworn and worn surfaces.
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| 43. |
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| 44. |
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| 45. |
- Cabanettes, Frederic, 1982-, et al.
(författare)
-
Global and local mapping of motor blocks liners roughness for the analysis of honing performance
- 2014
-
Ingår i: Journal of physics. - Bristol : Institute of Physics Publishing (IOPP). - 1742-6588 .- 1742-6596. ; 483:1
-
Tidskriftsartikel (refereegranskat)abstract
- The manufacturing and finishing (honing) of cylinder liners for the automotive industry is a constant challenge in order to reduce friction losses and oil consumption. A better knowledge of surfaces generated during plateau honing is then required for optimization of the process. Despite a well-known and controlled honing process, variations in surface roughness appear at both global (due to honing tool wear) and local (TDC, middle stroke, BDC) scales and need to be mapped and analysed. The following paper proposes to map the global and local variations in roughness by using a confocal 3D measuring equipment able to measure and scan any area of a cylinder liner. Six motor blocks (five liners each) are evaluated with twenty topography measurements per liner. In total, six hundred 3D measurements of size 1×1 mm are performed and roughness parameters are computed. The results show that some parameters do correlate with the honing tool wear specific to each cylinder. Experimental models could be built. Furthermore surface roughness varies significantly over the axial length of the liners due to waviness deviations combined with a lack of flexibility of the honing tool in axial direction. © Published under licence by IOP Publishing Ltd.
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| 46. |
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| 47. |
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| 48. |
- Cabanettes, Frédéric, 1982-, et al.
(författare)
-
The evolution of surface topography of injection cams
- 2007
-
Ingår i: Proceedings of the 11th International Conference on Metrology and Properties of Engineering Surfaces. - Huddersfield : Huddersfield University. - 9781862180574
-
Konferensbidrag (refereegranskat)
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| 49. |
- Cabanettes, Frederic, 1982, et al.
(författare)
-
The evolution of surface topography of injection cams
- 2007
-
Ingår i: Proceedings of Mets and Props conference 2007´, Huddersfield, UK. ; , s. 5-
-
Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Friction and wear are constant problems encountered in camshaft development. Among a wide amount of factors, surface topography is an important feature to improve in this complex system. Four parts of different shapes can be differentiated on an injection cam profile. Therefore the machining of such component is quite particular. Considering the complex shape of an injection cam, this paper is divided in two studies: 1. Variations of surface topography around freshly produced cams in order to emphasize the particular profile of cams which leads to a complex machining. 2. Evolution of surfaces during run-in in order to discover the effects of wear process on a group of roughness parameters. The results show a variation of density of peaks along the freshly produced cam surface and highlight also the importance of roller type on the evolution of topography. Further results show that summits of the surface are rounded off but not removed during run-in.
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| 50. |
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