镍基合金蜂窝材料冰固持条件下的超低温铣削研究

由于低刚度航天用薄壁镍基合金蜂窝材料在机械加工后常伴有卷曲、开焊、塌边等缺陷，故需改进其固持和加工方法。将该材料进行冰固持方法处理，采用数控铣床进行高速超低温加工。分析蜂窝铣削性能和加工缺陷产生原因，揭示冰固持超低温铣削机理。试验结果表明：相比于传统固持加工方式，冰固持超低温铣削后，蜂窝表面质量有很大提高，相关加工缺陷得到了有效抑制，切削深度对表面质量影响较大；获得了加工参数对铣削力影响顺序：切深最大，可提高3倍，其次为主轴转速，进给速度最小。该方法提高了蜂窝强度，改善了断屑方式。冰固持超低温工艺为面内径向等效强度小、低刚度薄壁金属蜂窝材料的高效加工提供了新方法。

Research on Milling of Ni-based Alloy Honeycomb Material at Ice Fixation and Cryogenic Temperatures

Considering the burr and collapse edge of machined low stiffness and thin-walled nickel-based alloy honeycomb material using in aerospace, the fixation and processing method should be improved. The material is treated by ice fixation method. CNC milling machine is used for the cryogenic processing. The honeycomb milling properties and the causes of machining defects are analyzed. Low-temperature milling mechanism of ice fixation is established. Results show that, compared to the traditional processing way, the quality of surfaces milled at ice fixation is significantly improved, and the processing defects are effectively suppressed. The cutting depth has greater influence on surface quality than spindle speed. The proposed method can be used to improve the strength of honeycomb. The effects of cutting parameters on milling force are analyzed: the cutting depth has the most significant effect on milling force, followed by spindle speed and feed speed.