Cutting, compression and shear of silicon small single crystals

Abstract

This paper describes the results of high speed deformations of pure silicon small crystals using molecular dynamics. The paper suggests that plastic deformation may be possible for silicon with a high speed deformation at room temperature. The potential used was the three body Stillinger–Weber potential. The size of the crystal is 6( x) × 16( y) × 2( z) [nm], with x, y and z axes being taken in the [1̄ 1 0], [1̄ 1̄ 2] and [1 1 1] directions, respectively. (1 1 1) is the cutting plane and a slip plane. [1̄ 1 0] is the cutting direction. A sharp vertical solid edge was advanced in the x direction with a speed of 10 m/s. Surfaces are free and no periodic boundary conditions were used. The time step interval was taken to be 1 × 10 −16 s. In another numerical experiment, the same crystal was compressed in the [1̄ 1̄ 1̄] direction also using molecular dynamics. It was found that silicon crystals can be compressed with a high speed deformation, and suggests that silicon may be plastically deformed under such conditions.