高速切削Inconel718切屑形成过程中塑性变形研究

Plastic deformation during the chip formation process in high-speed cutting Inconel718

镍基高温合金Inconel718是多组元复杂合金,在切削过程中,切屑变形复杂,切削温度高,形成锯齿形切屑。通过切削实验与仿真分析相结合的方法来研究切削Inconel718切屑形成过程中的塑性变形,结合切削实验获取的切屑根金相图片,分析锯齿形切屑演变过程与机理。结果表明:在切削过程中,材料温升导致热软化的发生,材料发生热剪切塑性失稳。同时由于位错引起的裂纹和内部空洞的聚合也加快了锯齿节块的滑移,最终导致锯齿形切屑的形成。

The nickel-based alloy Inconel718 is a multi-component complex alloy. There existed complex chip deformation,higher cutting temperature and formation of serrated chip in the process of machining Inconel718. In this paper,the plastic deformation during the process of chip formation in cutting Inconel718 is studied by the combination of cutting experiment and simulation analysis. Based on the metallographic images obtained in cutting experiments,the evolution and mechanism of serrated chip are analyzed. The results show that during the cutting process,the temperature rise of the material leads to the occurrence of thermal softening,and the thermoplastic shear instability further appears. At the same time due to cracks caused by dislocations and internal void polymerization also accelerate the jagged block slip,eventually leading to the formation of serrated chips.