Critical size, recovery, and mechanical property of nanoimprinted Ni–Al alloys investigation using molecular dynamics simulation

Abstract

The nanoimprinting process of nickel–aluminum (Ni–Al) alloys is studied using molecular dynamics (MD) simulations based on the many-body tight-binding potential. The effects of the temperature, loading and unloading velocities, holding/dwelling time, and composition of Ni–Al alloys are evaluated in terms of molecular trajectories, imprinting force, potential energy, stress, slip vector, and elastic recovery ratio. Simulation results show that the imprinting force increases with decreasing temperature and increasing loading velocity and Ni content. The average potential energy of a specimen decreases and its stress increases with increasing loading velocity. Slip planes of (1 1 0) and (1 1 0) form during Ni–Al alloy imprinting. During unloading, the adhesion force increases with increasing unloading velocity. The formability of a Ni–Al alloy can be enhanced by increasing the Ni content. Elastic recovery for a pattern can be avoided by decreasing the imprinting temperature and increasing the holding time. At a critical line width of 6.5 nm, elastic recovery ratios can be maintained in a range of 8–11%.