Microstructures and properties of welded joint of TiNi shape memory alloy and stainless steel^①

来源期刊：中国有色金属学报(英文版)2004年第3期

论文作者：邱小明 孙大谦 李明高 刘卫红

文章页码：475 - 479

Key words：TiNi shape memory alloy; stainless steel; welding; tensile strength; structure

Abstract: The fracture characteristics of the joint were analyzed by means of scanning electron microscope(SEM). Microstructures of the joint were examined by means of optical microscope, SEM and an image analyzer. The results show that the tensile strength of the inhomogeneous joint of TiNi shape memory alloy and stainless steel is lower than that of the homogeneous joint and a plastic field appears in the heat affected zone on the side of TiNi shape memory alloy. Because Ti- Ni shape memory alloy and stainless steel melted, a brittle as-cast structure was formed in the weld. The tensile strength and the shape memory effect of the inhomogeneous joint are strongly influenced by the changes of composition and structure of the joint. Measures should be taken to reduce the base metal melting and prevent the weld metal from the invasion by O for improving the properties of the TiNi shape memory alloy and stainless steel inhomogeneous joint.