薄壁壳体件装夹变形机理有限元分析与控制

摘要

The thin-wall shell workpiece with insufficient rigidity is liable to deform during the machining process, and the requirement of its planeness is very strict. The paper took a typical aeronautical aluminum-alloy for example. The finite element models were established to simulate the effect of locating points, clamping sequence and loading mode on the deformation of thin-wall shell part by the action of intensive load and even load. The result shows that the clamping forces are preferably applied step by step so that the deformation of thin-wall shell part can be effectively controlled and the planeness is further improved. In the same clamping sequence and loading mode, the uniform load is better than the concentrated load. The thickness of pad was optimized for uniform loading.%针对薄壁壳体件刚性较差,对表面平面度要求较高,而制造过程中极易产生装夹变形的难题,本文以典型的铝合金航空材料构件为例,采用有限元分析方法,对装夹过程中的薄壁壳体件装夹方案进行了优选,主要模拟了在集中载荷与均布载荷作用下,装夹位置、装夹顺序及加载方式对薄壁壳体零件产生变形的影响,结果表明夹紧力分步施加为较优方案,可以有效控制薄壁壳体零件变形,进而提高平面度.在相同装夹顺序、加载方式下,施加均布载荷优于施加集中载荷,并对均布载荷时采用垫铁的厚度进行了优化.