双孔微剪切评定焊接接头的局部强度  

Evaluation of local strength of welding joint by using double holes micro shear test

作　　者：蔡淑娟[1] 朱亮[1] 张忠发[1] 

机构地区：[1]兰州理工大学省部共建有色金属先进加工与再利用国家重点试验室,兰州730050

出　　处：《焊接学报》2016年第4期43-46,131,共4页Transactions of The China Welding Institution

基　　金：国家自然科学基金资助项目(51264026)

摘　　要：提出一种评价力学性能不均匀焊接接头强度的方法,研制了测量材料局部力学性能的双孔微剪切试验装置,对焊接接头各区域进行微剪切试验.记录加载过程中载荷传感器和位移传感器传输的数据,转化得到剪切应力-应变曲线.建立双孔微剪切试验的有限元模型,选择不同屈服应力和加工硬化指数的材料进行有限元模拟,建立试验剪切应力-应变曲线与材料强度参数的相关性,并利用拉伸试验对其准确性进行了验证.结果表明,利用双孔微剪切试验曲线可直接得到材料的强度参数,并利用双孔微剪切试验测定X70管线钢焊接接头上各区的强度.A new approach,double holes micro shear test,is presented for determining the localplastic deformation properties in welded joints.A device for measuring the local mechanical properties of materials is developed and the micro shear test of the welded joint is carried out.The response between applied load and indentor displacement is recoroled.shear stressstrain curve,the finite element model of double hole micro-shear lest is established.The finite element computation were carried out for various combination of yield stress and work hardening exponent.The equations were constructed to material strength properties and load-displacement curves from double holes microshear tests.The accuracy of this equations method is validated by tensile test.The results show that the material strength properties can be obtained directly from the experimental curves with double hole micro-shear test.The local distortion properties in X70 pipeline steel welded joints were evaluated by double holes micro shear test.

关 键 词：双孔微剪切试验 有限元模拟 屈服强度 抗拉强度 

分 类 号：TG407[金属学及工艺—焊接]