Abrasive wear of nanoscale single crystal silicon

Abstract

Nanoscale three-body and two-body abrasive wear on the monocrystalline silicon are investigated using a large-scale molecular dynamics approach. A nanoscale model of three-body abrasion is proposed to evaluate the movement pattern of a sphere particle. It is concluded that the rolling movement of a particle is observed without sliding in the present nanoscale computation process. It is found that there exists a large elastic recovery which prevents the sphere particle from sliding. A modified e/h criterion is proposed to predict the movement pattern of a particle. The result confirms the crucial effect of the elastic recovery on movement pattern. The plowing is also observed as a main wear pattern in three-body abrasion at the nanoscale, whereas the wear mechanism will transform from plowing into cutting at a large indentation depth for two-body abrasion. The cutting tendency is increased with increasing indentation depth. In both the three-body and two-body abrasion, friction force is directly proportional to normal force which governs the friction rule. A turning point is found lied on frictional line related to normal force, which indicates a transition of wear mechanism in two-body abrasion. It is also examined that three-body abrasion is able to cause more massive phase transformation than two-body abrasion although it is with shallower groove in three-body abrasion than in two-body abrasion.