铝合金厚板淬火残余应力的有限元模拟及其对加工变形的影响

 航空整体结构件在加工过程中容易发生较大变形。为了研究毛坯的初始残余应力对整体结构件加工变形的影响,采用准耦合方法,利用有限元软件ABAQUS模拟7075铝合金毛坯的淬火过程,研究该过程中温度的变化和残余应力的分布规律,并在含有淬火残余应力的毛坯上进行材料去除模拟。结果表明,模拟产生的比例件的变形与实际加工的比例件的变形非常近似,从而证明了毛坯的初始残余应力是引起整体结构件加工变形的主要因素,同时验证了准耦合淬火模拟的有效性。

Finite Element Method Simulation for Residual Stress in Quenched Aluminum Alloy Thick-Plate and Its Effect on Machining Distortion

Large aviation integrated structure part is prone to distortion during machining. To assess the effect of initial residual stress in blank on the deformation, a quenching analysis of 7075 aluminum alloy is carried out by employing a sequentially coupled thermal and mechanical procedure. The changing temperature and the resultant distribution of residual stress are investigated. Furthermore, redundant material is removed from the blank which possesses quenched residual stress, and a reduced scale large integrated structure part is obtained. Both the two steps are finished by using finite element code ABAQUS. To testify the finite element result, a reduced scale large integral structure part is machined from a quenched blank. Good agreement is found between the finite element method result and the test values. It is indicated that the original residual stress is the main factor to cause deformation, and the reliability of sequentially coupled thermal and mechanical method is tested at the same time.