大型薄壁整体结构件加工变形仿真

现代航空工业中为减轻飞机重量,提高飞机的各项机械性能,越来越多的使用整构件.加工大型整体薄壁构件时,有90%以上的材料被切削加工去除,由于材料去除后零件刚度的降低以及应力的释放,造成过大的加工变形.针对某薄壁零件加工后的变形问题,提出将加工薄璧整体结构件的铝合金毛坯分为粗加工毛坯和精加工毛坯进行加工的方法,建立了薄壁整体结构件加工变形仿真有限元模型并进行了仿真计算.仿真结果表明:通过增加粗加工毛坯的厚度,并先对粗加工毛坯进行切削加工成精加工毛坯,再在精加工毛坯的基础上进行薄璧零件的成形加工可以有效的减小薄璧零件的加工变形.随着粗加工毛坯厚度的的增加,精加工毛坯内部残余应力的分布更趋均匀,数值更小.

Simulation of Thin Wall Integral Structure Distortion During Machining

In order to reduce the weight of airplane and increase its mechanical behavior, more and more large integrated parts are applied in modern aviation industry. When machining thin-walled aero-plane parts, more than 90% of the materials could be removed, resulting in severe distortion of the parts due to the weakened rigidity and the release of residual stress. The reason which induced the distortion was analyzed and the method which classified the aluminum alloy blank as finish machining blank and rough machining blank were proposed to reduce the distortion. The finite element analysis model was established and the distortion of the thin wall integral structure was simulated. The result of simulation indicates that the machining distortion and the value of residual stress on finish machining blank was reduced effectively as the thickness of rough machining blank increased.