Molecular dynamics simulation on formation mechanism of grain boundary steps in micro-cutting of polycrystalline copper

Liu, Dehao1,2,3; Wang, Gang1,2,3; Yu, Jianchao1,2,3; Rong, Yiming (Kevin)1,2,4

2017-01

10.1016/j.commatsci.2016.10.001

COMPUTATIONAL MATERIALS SCIENCE   影响因子和分区

0927-0256

1879-0801

Three-dimensional molecular dynamics (MD) simulations were performed to investigate the formation mechanism of grain boundary (GB) steps in the micro-cutting of polycrystalline copper. The effects of the GB and misorientation angle on the surface quality were studied. Based on the simulation results, the surface maximum peak-to-valley height of polycrystalline copper was greater than that of single crystal copper owing to the formation of grain boundary steps. The dislocations continuously nucleated on the tool-workpiece interface were stopped and piled up at the GB. As the dislocations piled up at the GB, the dislocations became aligned and formed the sub-grain boundary to minimize the total system energy. Sub-grains with transitional crystal orientations formed at the GB during the micro-cutting of polycrystalline copper for the plowing of the cutting edge and crystal rotation. The misalignment in the slip directions between sub-grains and original grain resulted in the grain boundary step. A peak cutting force appeared at the GB in the cutting of polycrystalline owing to the geometrical hardening effects. It is revealed that the GB has a strong effect on the surface quality of a workpiece during the micro-cutting process. (C) 2016 Elsevier B.V. All rights reserved.

Molecular dynamics Micro-cutting Grain boundary steps Sub-grain Polycrystalline copper

SCI ; EI

英语

其他

Beijing Natural Science Foundation[3152013]

Materials Science

Materials Science, Multidisciplinary

WOS:000389089900048

ELSEVIER SCIENCE BV

20164402960195

Copper ; Crystal orientation ; Cutting tools ; Dislocations (crystals) ; Grain boundaries ; Micromachining ; Molecular dynamics ; Single crystals ; Surface properties

Copper:544.1 ; Machine Tool Accessories:603.2 ; Machining Operations:604.2 ; Physical Chemistry:801.4 ; Crystalline Solids:933.1 ; Crystal Lattice:933.1.1 ; Materials Science:951

MATERIALS SCIENCE

Web of Science

1.Tsinghua Univ, State Key Lab Tribol, Beijing 100084, Peoples R China
2.Tsinghua Univ, Inst Mfg Engn, Dept Mech Engn, Beijing 100084, Peoples R China
3.Tsinghua Univ, Beijing Key Lab Precis Ultra Precis Mfg Equipment, Beijing 100084, Peoples R China
4.South Univ Sci & Technol China, Mech & Energy Engn Dept, Shenzhen 518055, Peoples R China

Liu, Dehao,Wang, Gang,Yu, Jianchao,et al. Molecular dynamics simulation on formation mechanism of grain boundary steps in micro-cutting of polycrystalline copper[J]. COMPUTATIONAL MATERIALS SCIENCE,2017,126:418-425.

Liu, Dehao,Wang, Gang,Yu, Jianchao,&Rong, Yiming .(2017).Molecular dynamics simulation on formation mechanism of grain boundary steps in micro-cutting of polycrystalline copper.COMPUTATIONAL MATERIALS SCIENCE,126,418-425.

Liu, Dehao,et al."Molecular dynamics simulation on formation mechanism of grain boundary steps in micro-cutting of polycrystalline copper".COMPUTATIONAL MATERIALS SCIENCE 126(2017):418-425.