Study on the influence of crack propagation mechanisms in cutting SiCp/Al composites on surface integrity

SiCp/Al composites have extensive applications in the aerospace field, but they often encounter problems such as poor machinability and inferior surface quality during machining. Particle damage is a key factor affecting surface integrity, and the degree of damage mainly depends on the crack propagation path. At present, studies on the influence of crack propagation mechanisms on surface integrity remain insufficient. To address this issue, based on dislocation theory, this study proposes three theoretical models of crack propagation modes, and combines experimental investigations to study the crack propagation mechanism of SiCp/Al composites under different cutting speeds and its influence on surface integrity and mechanical properties. Through theoretical analysis and experimental verification, the intrinsic connection among "process parameters - crack propagation mechanisms - particle damage - surface integrity - mechanical properties" has been clarified.