| 1. |
- Cao, Pingxiang, et al.
(författare)
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Effect of rake angle on cutting performance during machining of stone-plastic composite material with polycrystalline diamond cutters
- 2019
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Ingår i: Journal of Mechanical Science and Technology. - : Springer. - 1738-494X .- 1976-3824. ; 33:1, s. 351-356
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Tidskriftsartikel (refereegranskat)abstract
- This study investigates the effect of rake angle on cutting performance during machining of stone-plastic composite material with diamond cutters. To that end, an orthogonal cutting experiment was designed, in which stone-plastic composite material was planed by a polycrystalline diamond (PCD) cutter to produce chips. The features studied include cutting forces, cutting heat, chip formation and cutting quality. The conclusions are as follows: Firstly, increased rake angle causes frictional force and resulting force to decrease, promoting an increase in normal force. Secondly, during planing, cutting heat is primarily distributed in the chips, with less retained in the cutting edge, and the least retained in the machined surface. The temperatures of both cutting edge and chip decline with an increase in rake angle. Thirdly, as rake angle increases, chip morphology changes from segmental to curved and then to particle chips, with chip-breaking lengths first increasing and then decreasing. Finally, an increased rake angle leads a more stable cutting process and improved cutting quality. Therefore, with the precondition of blade strength, a diamond cutter with a larger rake angle can be used to machine stone-plastic composite to improve production quality by forming a smoother machined surface.
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| 2. |
- Guo, Xiaolei, et al.
(författare)
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Cutting Forces and Chip Morphology during Wood Plastic Composites Orthogonal Cutting
- 2014
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Ingår i: BioResources. - : BioResources. - 1930-2126. ; 9:2, s. 2090-2106
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Tidskriftsartikel (refereegranskat)abstract
- The effect of chip thickness, rake angle, and edge radius on cutting forces and chip morphology in wood plastic composites (WPCs) orthogonal cutting was investigated. Three types of WPCs, Woodflour/polyethylene composite (WFPEC), wood flour/polypropylene composite (WFPPC), and wood flour/polyvinyl chloride composite (WFPVCC), that were tested exhibited different behavior with respect to the machinability aspects. The cutting forces of WFPVCC were the highest, followed by WFPPC and WFPEC. The most significant factor on the parallel cutting force of these three types of WPCs was the chip thickness, which explained more than 90%, contribution of total variation, while rake angle, edge radius, and the interactions between these factorshad small contributions. The most significant factor on the normal cutting force of WPCs was also the chip thickness, which accounted for more than 60% of the total variation. The chips produced included long continuous chips, short continuous chips, flake chips, and granule chips when cutting these three types of WPCs.
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| 3. |
- Guo, Xiaolei, et al.
(författare)
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Effect of average chip thickness and cutting speed on cutting forces and surface roughness during peripheral up milling of wood flour/polyvenyl chloride composite
- 2015
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Ingår i: Wood research. - 1336-4561. ; 60:1, s. 147-156
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Tidskriftsartikel (refereegranskat)abstract
- Wood flour/polyvinyl chloride composite (WFPVCC) is a kind of composite material that, over the years, is becoming more popular in constructions applications. In this work, cutting forces and machined surface roughness were studied during peripheral up milling of WFPVCC under different average chip thickness which was obtained by adjusting rotation speed and feed rate at both high and low speed cutting conditions. The results indicated that cutting forces components, parallel force (F-x) and normal force (F-y) greatly varied during the cutting process. Maximum F-x, maximum F-y and surface roughness increased with the increase of average chip thickness. Maximum F-x and maximum F-y at high speed cutting conditions were lower than that at low speed cutting conditions at a same average chip thickness. The machined surface roughness at high speed cutting conditions was better than that at low speed cutting conditions at a same average chip thickness. When meeting the requirement of certain surface roughness, higher cutting speed can allow higher chip thickness and then decrease the tool wear than lower speed cutting condition. Maximum negative F-y had great impact in machined surface roughness. Machined surface roughness increased with the increase of maximum negative F-y. Thus, high speed cutting conditions not only increase the machining productivity, but also decrease machined surface roughness during the peripheral up milling of WFPVCC.
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| 4. |
- Guo, Xiaolei, et al.
(författare)
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Effects of surface treatment on the properties of UV coating
- 2015
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Ingår i: Wood research. - 1336-4561. ; 60:4, s. 629-638
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Tidskriftsartikel (refereegranskat)abstract
- The influence of the surface treatment of raw medium-density fiberboard on the properties of 1st ultraviolet putty coating film and the effects of primer coating arrangement on the qualities of 1st ultraviolet primer film were investigated. With regard to surface roughness and the recorded adhesion of the coating film, there were significant variations when the surface treatment was modified or when the coating arrangement was changed. The findings led to the conclusion that there was a close relationship between the surface treatment as well as the coating arrangement and properties of the coating film.
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| 5. |
- Guo, Xiaolei, et al.
(författare)
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The cutting performance of Al2O3 and Si3N4 ceramic cutting tools in the milling plywood
- 2018
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Ingår i: Advances in Applied Ceramics. - : Taylor & Francis. - 1743-6753 .- 1743-6761. ; 117:1, s. 16-22
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Tidskriftsartikel (refereegranskat)abstract
- This research focuses on the cutting performance of Al2O3 and Si3N4 ceramic cutting tools in upmillingplywood, the results of which are as follows. First, whether the tool material is Al2O3 orSi3N4 ceramic, the cutting forces at low-speed cutting were less than those at high-speedcutting, and the machining quality at low-speed cutting was greater than that at high-speedcutting. Then, whether at low- or high-speed cutting, the cutting forces of Al2O3 cutting toolswere higher than those of Si3N4 cutting tools, and the machining quality of plywood milledby Al2O3 ceramic cutting tools was poorer than that milled by Si3N4 ceramic cutting tools.Finally, Si3N4 ceramic cutting tools were more suitable to machine the wooden productionswith much glue content than Al2O3 ceramic cutting tools for the better machined quality.
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| 6. |
- Guo, Xiaolei, et al.
(författare)
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Tool wear and machined surface roughness during wood flour/polyethylene composite peripheral upmilling using cemented tungsten carbide tools
- 2014
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Ingår i: BioResources. - : BioResources. - 1930-2126. ; 9:3, s. 3779-3791
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Tidskriftsartikel (refereegranskat)abstract
- The effect of sharpness angle on tool wear and the effect of tool wear on machined surface roughness were investigated in wood flour/polyethylene composite (WFPEC) peripheral up-milling using cemented tungsten carbide (TC) tools. It was shown that nose width and edge recession increased with increasing feeding length. During the milling process, the wear of the nose width was smallest for the tool with a sharpness angle of 45°, followed by tools with sharpness angles of 55° and 65°. The wear of edge recession was highest for the tool with a sharpness angle of 45°, followed by tools with sharpness angles of 55° and 65°. The nose width increased with increasing sharpness angle, the edge recession decreased with increasing sharpness angle, and the machined surface roughness increased with increasing sharpness angle after a feeding length of 40 m. The nose width had a positive effect on the machined surface roughness, and the machined surface roughness increased with increasing nose width. The edge recession had little effect on the machined surface roughness. The clearance face roughness of the worn tool increased with increasing sharpness angle. The analysis of the SEM micrographs and EDS of the clearance face of the worn tool showed that the wear mechanisms of the cemented tungsten carbide tool were oxidation and abrasion in the range tested during cutting. Thus, a slight wear of the edge recession is gained in exchange for a lower machined surface roughness by decreasing the sharpness angle.
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| 7. |
- Li, Rongrong, et al.
(författare)
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A Novel Sawing Method for Small-Diameter Log
- 2015
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Ingår i: Wood research. - 1336-4561. ; 60:2, s. 293-300
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Tidskriftsartikel (refereegranskat)abstract
- The commercial feasibility of sawmilling mainly depends on the expected productionyield. At the same time, the choice of sawing method is one of primary factors affecting yield.Therefore, choosing a reasonable sawing method is also necessary in small-diameter logs sawingprocess. In this study, a novel sawing method was proposed, and a comparison was made betweenthe volume yield for the most common sawing method in China, and the yield produced by anovel sawing method. This study shows that hexagon sawing give higher yield than the othersawing methods. The mean yield for the whole diameter range is: 82.7 % for hexagon sawing,53.3 % for live sawing, 56.7 % for hexagon sawing, 63.2 % for hexagon sawing.
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| 8. |
- Li, Rongrong, et al.
(författare)
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Effect of Pressure, Feed Rate, and Abrasive Mass Flow Rate on Water Jet Cutting Efficiency When Cutting Recombinant Bamboo
- 2015
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Ingår i: BioResources. - : BioResources. - 1930-2126. ; 10:1, s. 499-509
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Tidskriftsartikel (refereegranskat)abstract
- Recombinant bamboo with a thickness of 15 mm was drilled on a CNC machine. The process parameters considered were spindle speed, feed rate, and diameter of the drill, and the response parameters were thrust force and torque. Mathematical models were developed to establish the relationship between the process parameters and the response parameters. The results showed that the main influence on thrust force came from spindle speed and feed rate. High spindle speed with low feed rate was a combination that minimized the thrust force. The process parameters that have a major effect on torque are the diameter of the drill and the spindle speed.
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| 9. |
- Li, Rongrong, et al.
(författare)
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Experimental and Numerical Study of Moisture-induced Stress Formation in Hexagonal Glulam Using X-ray Computed Tomography and Finite-element Analysis
- 2018
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Ingår i: BioResources. - : University of North Carolina Press. - 1930-2126. ; 13:4, s. 7395-7403
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Tidskriftsartikel (refereegranskat)abstract
- Hexagonal glue-laminated timber with large cross-sections, made from small diameter logs, was studied. Effects of relative humidity variations on the moisture-induced stresses were investigated to evaluate how the prediction model compared to a real outcome. The test samples were exposed to an environment with relative humidity variations from 80% to 30%. The moisture content inside the samples was measured via X-ray computed tomography scanning. A moisture transport and a hygromechanical finite element simulation model was used for the prediction of moisture content and resulting stress distribution. The results from both the test and simulation showed that the moisture content in the edge angles of the samples dropped rapidly due to a large moisture diffusion rate. The moisture gradient was generated via a different moisture transfer rate at the inner and external parts of the samples. The maximum stress perpendicular to the grain in the simulation was 8 MPa and was located at the surface near the corners. This stress peak caused cracking according to the model, which was also seen in the test samples. The results for the measured moisture content agreed with the simulated results and this indicated that the moisture transfer model was adequate for simulation.
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| 10. |
- Li, Rongrong, et al.
(författare)
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Investigation of Glueline Shear Strength of Pine Wood Bonded with PVAc by Response Surface Methodology
- 2015
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Ingår i: BioResources. - : BioResources. - 1930-2126. ; 10:3, s. 3831-3838
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Tidskriftsartikel (refereegranskat)abstract
- The effects of process parameters (adhesive spread, press time, and applied pressure) on the response parameter (shear strength) of pine wood bonded with PVAc were studied. Response surface methodology was applied for design of experiments and for analysis of results. A mathematical model was developed to establish the relationship between the process parameters and response parameters. The results showed that the major factors were adhesive spread and applied pressure. The shear strength increased as the adhesive spread and applied pressure increased within certain ranges.
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