带环形焊缝双金属复合管屈曲失效研究

The three-dimensional finite element model of the bi-material metal pipes with girth weld was established. Considering the residual stress in the process of bi-material metal pipes composite forming, the buckling failure mechanism of bi-material metal pipes with girth weld under complex load was studied. The effects of the girth weld, the wall thickness of lined pipe, the outer diameter of outer pipe, the initial gap between lined and outer pipe and the yield strength of lined pipe on buckling failure and deformation of bi-material metal pipes were analyzed. The results show that the existence of girth weld obviously decreases the curvature of the lined pipe of bi-material metal pipes when buckling failure occurs. The increase of the outer diameter of outer pipe, the initial gap between lined and outer pipe, and the yield strength of lined pipe, and the decrease of the wall thickness of lined pipe can make the bi-material metal pipes with girth weld more prone to buckling failure.