Study on micro-plastic behavior and tribological characteristics of granular materials in friction process

Purpose This paper aims to investigate the micro-plastic behavior of granular material in three-body friction interface and its effect on friction characteristics. Design/methodology/approach A numerical model of particle breakage in friction contact was constructed based on the discrete element method. The influence of friction pair working condition and internal bonding strength on the micro-plastic behavior of particulate matter was analyzed. A reciprocating linear tribometer was used to verify the simulation results. Findings The results show that when the granular materials are squeezed and sheared by the friction pair, a shear zone inclined to the left is gradually formed, which leads to particle breakage. The breakage of the particle leads to the reduction of load-bearing capacity and the increase of friction coefficient. Due to the differences in bond strength and friction pairs working conditions, the particle plastic behavior is divided into the following three states: elastic deformation, breakage and plastic rheology. Originality/value This study is helpful to understand the effect of the micro-plastic behavior of particles on the three-body friction characteristics.