Effect of Friction Depth, Velocity, and Cu Content on the Friction Behavior of AgCu Alloy by Molecular Dynamics Simulation

Abstract The AgCu alloy is widely used in numerous industries such as electronics and electrical engineering due to its excellent electrical conductivity, thermal conductivity, and workability. However, the friction problems during its service can seriously affect the operational stability and service life. Therefore, it is of great significance to deeply explore the friction and wear behavior of the AgCu alloy. In this study, the molecular dynamics simulation method was employed to conduct an in-depth investigation of the friction and wear behavior of AgCu alloy with different friction depths, velocities, and Cu contents. It found that as the depth increases, the contact area enlarges, and the atomic packing, phase transformation, and dislocations increase, resulting in a roughly linear increase in the average and normal friction force. The characteristic of this wear mechanism is that it will create grooves on the surface and cause material transfer. At friction speeds of 0.5 Å/ps, 1 Å/ps, and 1.5 Å/ps, the average friction force increases with the increase of speed, accompanied by expanded strain localization and reduced twinning with intensified temperature under dynamic loading. The content of the Cu has a significant impact on the friction behavior. When the content increases, the softening of the alloy leads to a linear decrease in the average friction force. At the same time, the plasticity is enhanced, the strain region expands, and the disordered atomic structures increase. The results of this study provide an important theoretical basis for a deep understanding of the friction and wear mechanism of the AgCu alloy and the optimization of its performance.