Analysis of the Creep Failure of P92/HR3C Dissimilar Steel Welded Joint

Abstract

Harsh service environments, such as high temperature and pressure, cause many unforeseen premature failures, especially for welded joint structures, whose heat-affected zones have been in service. Cases of pressure vessel damage caused by premature cracking in the process often occur. In this paper, the finite element model of dissimilar welded joints of P92/HR3C steel was established to simulate the actual service process, and the variation law of maximum principal stress, equivalent stress, and stress triaxiality on the inner and outer surfaces of the joint and both sides of the welding were analyzed. The results show that in the long-term use of welded joints, the stress concentration occurs in the weld fusion zone; with the increase in service time, the creep strength of the HR3C weld interface is much higher than the P92 weld interface, the structural shape changes and the stress concentration is transferred from the HR3C-weld to the P92-weld.