异种钢接头沿界面蠕变脆断的力学控制参量

On Mechanical Parameter Controlling Creep Brittle Rupture Along Interface of Dissimilar Metal Welded Joints

沿焊缝界面发生的蠕变脆性断裂是异种钢接头早期失效的典型特征，本文利用有限元计算、高温密栅云纹和蠕变断裂试验方法，分析了铬－钼－钒系异种钢接头的蠕变应变分布特性，提出了临近界面低强母材侧的应力三轴度（σ＿ｈ／σ）是控制接头早期脆性断裂的主要力学控制参量的观点。

Creep brittle rupture along the weld interface is a typical premature failurecharacteristic of dissimilar metal welded joints,In this paper,the creep strain distribution of CrMoV dissimilar metal welded joints was analysed by means of FE calculation, thermostablemoire and creep rupture teSts. It is concluded that the stress triaxiality(σ_h/σ)in thelow-strength base metal adjacent to the interface is a predominant mechanical parametercontrolling the premature brittle rupture of the joints.