Wear evolution of a brazed single diamond grain in ultrasonic vibration-assisted grinding of high volume fraction SiCp/Al composites

Abstract

High volume fraction silicon carbide particle-reinforced aluminum matrix (SiC_p/Al) composites combine the low density of Al alloy with the high stiffness and wear resistance of SiC particles, making them ideal for high-performance equipment manufacturing. However, the high hardness and densely uneven distribution of SiC particles lead to frequent impacts and unstable loading on abrasive grains during conventional grinding (CG), accelerating grain wear and degrading workpiece surface quality. This paper proposes an ultrasonic vibration-assisted grinding (UVAG) method using single diamond grain (SDG) to investigate grain wear behavior and its influence on the material removal. The grinding performance of the SDG, the evolution of grinding forces and grain morphology during wear, and their effects on material removal are analyzed. Results show that UVAG introduces dynamic oscillatory loads, which effectively reduce peak forces, mitigate grain wear, and extend the steady wear stage. Compared with CG, UVAG lowers the grinding force by 19.7 % in the initial state and by 17.3 % during steady wear. The diamond grain primarily undergoes abrasive wear and tends to adhere to the Al matrix and brazing alloy. Under UVAG, the wear width and height of the cutting edges are reduced by 24.9 % and 21.4 %, respectively. As wear intensifies, the workpiece surface shows a flow-like morphology and pronounced adhesion. The pile-up volume ratio and surface roughness S_a under CG are 13.1 % and 15.4 % higher, respectively, than those under UVAG. This study establishes an analytical foundation and offers practical guidance for precision grinding of particle-reinforced composites.