| 1. |
- Abiri, Olufunminiyi, et al.
(författare)
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Controlling Thermal Softening Using Non-Local Temperature Field in Modelling
- 2016
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Ingår i: Journal of Machining and Forming Technologies. - : Nova Science Publishers, Inc.. - 1947-4369. ; 8:1-2, s. 13-28
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Tidskriftsartikel (refereegranskat)abstract
- One of the aims of this work is to show that thermal softening due to the reduced flow strength of a material with increasing temperature may cause chip serrations to form during machining. The other purpose, the main focus of the paper, is to demonstrate that a non-local temperature field can be used to control these serrations. The non-local temperature is a weighted average of the temperature field in the region surrounding an integration point. Its size is determined by a length scale. This length scale may be based on the physics of the process but is taken here as a regularization parameter.
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| 2. |
- Abiri, Olufunminiyi, et al.
(författare)
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Non-Local Modelling of Strain Softening in Machining Simulations
- 2017
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Ingår i: IOP Conference Series. - : Institute of Physics (IOP). - 1757-8981 .- 1757-899X. ; 225
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Tidskriftsartikel (refereegranskat)abstract
- Non-local damage model for strain softening in a machining simulation is presented in this paper. The coupled damage-plasticity model consists of a physically based dislocation density model and a damage model driven by plastic straining in combination with the stress state. The predicted chip serration is highly consistent with the measurement results.
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| 3. |
- Kalhori, Vahid, et al.
(författare)
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Simulation of mechanical cutting using a physical based material model
- 2010
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Ingår i: International Journal of Material Forming. - : Springer Science and Business Media LLC. - 1960-6206 .- 1960-6214. ; 3:Suppl. 1, s. 511-514
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Tidskriftsartikel (refereegranskat)abstract
- A dislocation density material model based on model-based-phenomenology has been used to predict orthogonal cutting of stainless steel Sanmac 316L. The chip morphology and the cutting forces are used to validate the model. The simulated cutting forces and the chip morphology showed good conformity with practical measurements. Furthermore, simulation of cutting process utilizing the dislocation density based material model improved understanding regarding material behaviour such as strain hardening and shear localization at the process zone.
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| 4. |
- Lindgren, Lars-Erik, et al.
(författare)
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Improved and simplified dislocation density based plasticity model for AISI 316 L
- 2017
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Ingår i: Mechanics of materials. - : Elsevier. - 0167-6636 .- 1872-7743. ; 108, s. 68-76
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Tidskriftsartikel (refereegranskat)abstract
- A previously published dislocation density based flow stress model has been refined and made more consistent with underlying physical assumptions. The previous model included many temperature dependent parameters that are taken as constant in the current work. The model has also been simplified with respect to dynamic strain aging. Additional contributions to flow stress from the Hall-Petch effect and solute hardening have now been explicitly included in the model. Furthermore, the dynamic recovery part of the model has been improved.
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| 5. |
- Lindgren, Lars-Erik, et al.
(författare)
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Material modelling and physical based models with particular emphasis on high strain rates
- 2009
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Ingår i: International Symposium on Plasticity 2009.
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- The problem of calibrating material models with tests in a limited range of conditions and then applying outside this range is discussed. This is the case when machining simulations are performed where very high strain rates (>50000s-1) can be obtained. The paper discusses the Johnson-Cook model, an empirical model that is common for high strain rate applications and a physical based dislocation density model. Test data for AISI 316L ranging from 0.001 to 10s-1 and room temperature up to 1300°C are used for calibration of the models and thereafter additional tests up to 9000s-1 at varying initial temperatures are compared with the model predictions
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| 6. |
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| 7. |
- Lindgren, Lars-Erik, et al.
(författare)
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Towards predictive simulations of machining
- 2016
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Ingår i: Comptes rendus. Mecanique. - : Elsevier BV. - 1631-0721 .- 1873-7234. ; 344:4-5, s. 284-295
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Tidskriftsartikel (refereegranskat)abstract
- Machining simulations are challenging with respect to both numerical issues and physical phenomena occurring during machining. The latter are mainly related to the description of the bulk material behaviour (plasticity) and surface properties (friction and wear). The aim of this paper is to present what is required for predictive models, depending on their scopes, as well as the needed developments for the future. The paper includes a short review of selected works that are relevant for this purpose as well as conclusions based on our own experience
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| 8. |
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| 9. |
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| 10. |
- Svoboda, Ales, et al.
(författare)
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Simulation of metal cutting using a physically based plasticity model
- 2010
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Ingår i: Modelling and Simulation in Materials Science and Engineering. - : IOP Publishing. - 0965-0393 .- 1361-651X. ; 18:7
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Tidskriftsartikel (refereegranskat)abstract
- Metal cutting is one of the most common metal shaping processes. Specified geometrical and surface properties are obtained by break-up of the material removed by the cutting edge into a chip. The chip formation is associated with a large strain, high strain rate and a locally high temperature due to adiabatic heating which make the modelling of cutting processes difficult. This study compares a physically based plasticity model and the Johnson-Cook model. The latter is commonly used for high strain rate applications. Both material models are implemented into the finite element software MSC.Marc and compared with cutting experiments. The deformation behaviour of SANMAC 316L stainless steel during an orthogonal cutting process is studied.
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