PSI - Issue 43

Kevin Blixt et al. / Procedia Structural Integrity 43 (2023) 9–14

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Author name / Structural Integrity Procedia 00 (2022) 000 – 000

Fig. 6. Fig. 4a) with red atoms above d and blue atoms below d. The line shows the original workpiece height. r = 200nm.

Fig. 7. Temperature distribution at velocities: a) v c = 100m/s and b) v c = 300m/s. Orientation [100]. R = 200nm.

5. Conclusions Nanometric cutting of a copper workpiece by a stiff cylindrical cubic diamond tool has been investigated using MD simulations. The focus is on the effects of different crystallographic orientations of the workpiece. Three crystallographic orientations, named [100], [110] and [111], were treated. The cutting force increases rapidly in the beginning of the cutting process and stabilizes as the tool advances over the workpiece. No significant difference in the cutting force magnitude was observed for the different crystallographic orientations despite significantly different deformation patterns. During the cutting process, the chip forms in an evolutionary manner. Small cutting velocities or large tool radii results in material pileup at the surface and no chip is formed. Small tool radii create long chips that fall backward, and fold over the tool. A chip might also form by folding of itself, thus increasing the chip thickness after each fold. This effect is enhanced by increasing cutting velocity, which also creates longer chips. A higher overall temperature is observed for higher cutting velocity, and maximum temperature is observed just beneath the tool which might affect the tool durability. References Daw, M.S. and Baskes, M.I., 1984. Embedded-atom method: Derivation and application to impurities, surfaces, and other defects in metals, Phys. Rev. B 29, 644 Foiles, S.M., Baskes, M.I. and Daw, M.S., 1986. Embedded-atom-method functions for the fcc metals Cu, Ag, Au, Ni, Pd, Pt, and their alloys. Physical review B, Vol. 33, No. 12. Hansson, P., Ahadi, A. and Melin, S., 2022. Molecular dynamic modelling of the combined influence from strain rate and temperature at tensile loading of nanosized single crystal Cu beams. Materials Today Communications 31 (2022) 103 277 Kelchner, C.L., Plimpton, S.J. and Hamilton, J.C., 1998. Dislocation nucleation and defect structure during surface indentation Phys. Rev. B 58:11085-8 Melin, S., Hansson, P. and Ahadi, A., 2019. Grain boundary influence on the mechanical response to tensile loading for nanosized copper beams modelled by MD simulations. Structural Integrity Procedia 00 (2019) 000-000 www.sciencedirect.com Plimpton, S., 1995. Fast Parallel Algorithms for Short-Range Molecular Dynamics, J. Comp. Phys. 117, 1-19 Stukowski, A., 2010. Visualization and analysis of atomistic simulation data with OVITO – the Open Visualization Tool. Modelling Simul. Mater. Sci. Eng. 18. Zhang, L. and Tanaka, H., 1997. Towards a deeper understanding of wear and friction on the atomic scale — a molecular dynamics analysis Wear 211 (1997) 44-53 Zhen, T., Yingchun, L., Xuechun, Y. and Xichum, L., 2014. Investigation on the thermal effects during nanometric cutting process while using nanoscale diamond tools. International Journal of Advanced Manufacturing Technology 74.9-12, 1709-1718