耳片接头的断裂失效数值模拟

Fracture Failure Numerical Simulation of Lug Joint Structure

金属材料断裂研究属于工程计算中的难点问题。目前对于金属构件延性断裂问题的研究,多是基于10种经典塑性材料断裂试样,分析构件延性断裂的表征参数和断裂机理,对延性金属断裂准则在耳片接头类结构中的应用研究较少。本文对4种结构形式的耳片接头进行拉伸断裂试验,采用应力三轴度准则,模拟接头在拉伸试验中的断裂失效,对比接头的结构形式对断裂性能的影响和算法精度。研究表明:在材料的线弹性阶段,4种接头的位移变形基本一致;接头的断面主要集中在耳片开孔中心位置;在耳片开孔处增加凸台,可以提高接头的断裂强度;立筋、R角对接头断裂性能影响较小。

Fracture of metallic materials is a difficult problem in engineering calculation.At present,researches on the ductile fracture of metal components are mostly based on the fracture samples of 10 kinds of classical plastic materials to analyze the characterization parameters and fracture mechanism of the ductile fracture of components,and there are few studies on the application of ductile metal fracture criteria in lugs and joints.Tensile fracture tests are carried out on lug joints of four types of structures.The fracture failure of lug joints in tensile tests is simulated by using the stress triaxial criterion,and the influence of joint structure on fracture performance and the accuracy of the algorithm are compared.Study shows that:at the linear elastic stage of the material,the displacement and deformation of the 4 joints are basically the same;the cross section of the joint is mainly concentrated in the center of the opening of the lug;the fracture strength of the joint can be improved by adding a boss at the opening of the lug;the effect of stud and R-angle and different loading rate on the fracture property of the joint is little.