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Atomic Simulations of Deformation Mechanism of 3C-SiC Polishing Process with a Rolling Abrasive

Abstract

In the present study, molecular dynamics (MD) simulations are applied to investigate the polishing process of cubic silicon carbide (3C-SiC) with a rotating abrasive. The influence of abrasive rotational speed and rotation axis orientation on the friction characteristics and deformation behaviors of 3C-SiC is studied. The results show that as the rotational speed increases, the normal force first increases until it reaches its maximum at 25 rad/ns and then decreases. The evolution of transverse force with the rotational speed is more complicated and the smallest transverse force and friction coefficient are obtained at the rotational speed of 50 rad/ns. Besides, the transverse force increases while the normal force decreases with the rotation angle when the angular velocity vector of the rotational abrasive is parallel to the substrate surface. The case when the rotational speed is 25 rad/ns and the rotation angle is 0 is a significant critical situation. At the critical situation, we observe the lowest material removal rate, the deepest subsurface damage layer, the biggest high stress region and the smallest high temperature region for all rotational speeds and rotation axis orientations. Moreover, in the simulations, phase transformation (mainly amorphization) induced by high pressure is more pronounced than that by thermal effect. The results gained can shed light on the atomic-scale material removal and deformation mechanisms of 3C-SiC during polishing process.

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Acknowledgements

This work is supported by Beijing Natural Science Foundation (No. 3202024), National Natural Science Foundation of China (Nos. 51405337 and 51875405), Tribology Science Fund of State Key Laboratory of Tribology (No. SKLTKF20B13) and Beijing Institute of Technology Research Fund Program for Young Scholars. The MD simulations in this paper are performed on the China National Grid (http://www.cngrid.org) / China Scientific Computing Grid (http://www.scgrid.cn) [66].

Funding

This work is supported by Beijing Natural Science Foundation (No. 3202024), National Natural Science Foundation of China (Nos. 51405337 and 51875405), Tribology Science Fund of State Key Laboratory of Tribology (No. SKLTKF20B13) and Beijing Institute of Technology Research Fund Program for Young Scholars.

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Correspondence to Pengzhe Zhu.

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Yin, Z., Zhu, P., Li, B. et al. Atomic Simulations of Deformation Mechanism of 3C-SiC Polishing Process with a Rolling Abrasive. Tribol Lett 69, 146 (2021). https://doi.org/10.1007/s11249-021-01526-7

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Keywords

  • Molecular dynamics
  • 3C-SiC
  • Polishing
  • Rolling abrasive
  • Deformation behaviors