液氮冷却对铁基形状记忆合金车削加工性能的影响研究

Research on Investigation on Cutting Effect of Cylindrical Turning Fe-based Memory Alloy with Liquid Nitrogen as Coolant

针对铁基形状记忆合金常规冷却切削条件下因材料自身相变点及热滞性所出现的表面加工质量差、超弹性性能受损、切削效率低等问题,研究液氮冷却对改善形状记忆合金性能的影响。设计液氮喷淋低温冷却车削Fe-Mn-Si-Cr-Ni-C系形状记忆合金试验,研究了液氮喷淋低温冷却、常规水基切削液冷却、干切削等不同冷却方式、不同工艺参数下切削振动以及表面粗糙度的变化特性,分析了不同冷却方式对切削表层微观组织结构的影响。结果表明,液氮冷却能较好地改善铁基形状记忆合金的切削性能及微观组织。

Aiming at the technical problems such as poor surface quality,hyper elastic property damage and low cutting efficiency in conventional cooling cutting of the Fe-based shape memory alloy,the effect of liquid nitrogen cooling on improving the properties of shape memory alloy is researched. A Fe-Mn-Si-Cr-Ni-C series shape memory alloy turning experiment which using the liquid nitrogen as the cooling lubricant is designed.The characteristics of cutting vibration and surface roughness variation under different process parameters and cooling modes,such as liquid nitrogen spray low-temperature cooling,conventional water-based cutting fluid cooling and dry cutting are studied.The result shows that the liquid nitrogen cooling method can significantly improve the cutting performance and microstructure of Fe-based shape memory alloy.