SiC_p/Al复合材料切削仿真及实验研究

Study on Cutting Simulation and Experiment of SiC_p/Al Composites

对SiC_p/Al复合材料的颗粒和基体分别进行定义建立有限元仿真模型,使用ABAQUS有限元软件从微观角度分析了不同切削速度和切削深度对切削力的影响以及应力场分布情况,研究切屑的形成过程、基体和颗粒的内部应力分布、刀具和颗粒之间的相互作用以及简要分析了材料表面缺陷的成因,通过车削实验进行验证。研究表明:微观仿真模型中由于高硬度SiC颗粒的存在会产生大量的微裂纹以及单一小空洞和不连续空洞,形成表面缺陷,且剪切区域微裂纹的扩展是产生切屑的重要因素;通过对比,实验获得的切削力变化及其波动和形成机制与仿真结果一致。

This paper establishes the finite element simulation model that defines the characteristic of SiC particles and Al matrix respectively, and analyzes the influence of cutting depth and cutting speed on cutting forces and the distribution of stress field to study chips＇forming process, internal stress distribution of matrix and particles, the interaction among tool and particles. This paper briefly analyzes the reason of machined surface defects and verifies through turning experiment. The research indicates that a mass of micro-cracks and single and discrete cavities emerge because of high hardness SiC particles which results in surface defects in microscopic model. Propagation of micro-crack in shear zone is a key factor for chips emergence. By means of comparison, the variation and fluctuation of cutting force as well as formation mechanism obtained from the experiment are consistent with the simulation results.