残余应力对航空整体结构件加工变形的影响分析

基于理论计算和有限元模拟,研究了毛坯的初始残余应力对大型整体结构件数控加工变形的影响,对单向 应力作用的矩形截面梁在剥层过程中的变形挠度值进行了求解。结果表明,理论解与有限元计算值是一致的。面 向工程应用,采用ABAQUS有限元软件模拟了残余应力对隔框类整体结构件加工变形的影响,并进行了试验验证。 有限元仿真结果与试验数值非常吻合。最后,根据工件加工变形的有限元模拟结果,提出了提高整体结构件制造 精度的工艺措施。

Study on machining distortion of unitization airframe due to residual stress

Based on theoretical calculation and finite element simulation, the influence of original residual stress on the machining distortion of large unitization airframe is studied. The deformation deflection of the rectangular section beam, which is acted by one direction residual stress, is calculated while the material is removed. The theoretical solution agreed well with the finite element result. Cater to the engineering application, the effect of residual stress on machining distortion of frame unitization part is simulated by employing ABAQUS software. An experiment is conducted to validate the FEM result. Good agreement is found between the finite element result and the experiment values. Finally, upon the simulation result of the machining distortion, manufacturing process is put forward to improve machining precision of unitization airframe.