Numerical Simulation on Interfacial Creep Failure of Dissimilar Metal Welded Joint between HR3C and

• 作 者: 张建强 TANG Yi ZHANG Guodong ZHAO Xuan GUO Jialin LUO Chuanhong
• 机 构: Key Laboratory of Hubei Province of Water Jet Theory and New Technology, Wuhan University,Research I
• 出 处: Journal of Wuhan University of Technology(Materials Science)
• 发表日期: 2016年05期
• 关键词: creep welded nucleation expand Mises joints exactly outer constrain vicinity

The maximum principal stress, von Mises equivalent stress, equivalent creep strain, stress triaxiality in dissimilar metal welded joints between austenitic(HR3C) and martensitic heat-resistant steel(T91) are simulated by FEM at 873 K and under inner pressure of 42.26 MPa. The results show that the maximum principal stress and von Mises equivalent stress are quite high in the vicinity of weld/T91 interface, creep cavities are easy to form and expand in the weld/T91 interface. There are two peaks of equivalent creep strains in welded joint, and the maximum equivalent creep strain is in the place 27-32 mm away from the weld/T91 interface, and there exists creep constrain region in the vicinity of weld/T91 interface. The high stress triaxiality peak is located exactly at the weld/T91 interface. Accordingly, the weld/T91 interface is the weakest site of welded joint. Therefore, using stress triaxiality to describe creep cavity nucleation and expansion and crack development is reasonable for the dissimilar metal welded joint between austenitic and martensitic steel.

The maximum principal stress, von Mises equivalent stress, equivalent creep strain, stress triaxiality in dissimilar metal welded joints between austenitic (HR3C) and martensitic heat-resistant steel (T91) are simulated by FEM at 873 K and under inner pressure of 42.26 MPa. The results show that the maximum principal stress and von Mises equivalent stress are quite high in the vicinity of weld / T91 interface, creep cavities are easy to form and expand in the weld / T91 interface. There are two peaks of equivalent creep. joint, and the maximum equivalent creep strain is in the place 27-32 mm away from the weld / T91 interface, and there exists creep constrain region in the vicinity of weld / T91 interface. The high stress triaxiality peak is located exactly at the weld / T91 interface. Thus, the weld / T91 interface is the weakest site of welded joint. Therefore, using stress triaxiality to describe creep cavity nucleation and expansion and crack development is reasonable for the dissimilar metal welded joint between austenitic and martensitic steel.