Molecular dynamics study on shear deformation of b-silicon nitride single crystal
Ogata Shigenobu; Kitagawa Hiroshi; Hirosaki Naoto; Yasumoto Hiroaki
Abstract:The deformation properties of b-silicon nitride under shear loading are investigated by molecular dynamics simulation using a three body empirical potential. Two cases of shear deformation, {101 over bar 0} < 00001 > and {101 over bar 0} < 12 over bar 10 >, are analyzed, which are reported as the slip systems on the basis of experimental observation. The ideal shear strength of the b single crystal along these directions is somewhat smaller than the one of a-silicon nitride single crystal reported previously. Slip deformations take place in narrow bands, thickness of which are very thin. For the {101 over bar 0} < 0001 > case, it is almost equal to the distance between the nearest neighbor atoms and for the {101 over bar 0} < 12 over bar 10 > case about 0.4 nm. Key Words:Molecular dynamics, b-silicon nitride, Slip system, Shear deformation, Sliding mechanism, Three body potential