Influence of Surface Pits on Roughness in Single-Point Diamond Turning of Particle-Reinforced Polymer Composites: A...

In this study, the surface pit formation mechanism during single-point diamond face turning of a particle-reinforced polymer matrix composite (PRPMC) was investigated using finite element simulations. Based on the identified pit formation mechanisms, a surface roughness prediction model was developed and validated through face turning experiments. The results show that particle fracture and interfacial debonding are the primary origins of surface pits. Increasing cutting depth promotes the transition from particle fracture to interfacial debonding, leading to larger pits and higher surface roughness. A rake angle of -15° and a larger tool nose radius improve surface quality by suppressing pit formation and plastic side flow. The proposed model accurately predicts the effects of cutting depth, rake angle, and tool nose radius on surface roughness, with a maximum prediction error of 9.20% and an average error of 4.66%. This study provides a theoretical basis for surface roughness prediction and process parameter optimization in single-point diamond face turning of PRPMCs.