Prediction of Welding Residual Stress in 2.25Cr-1Mo Steel butt welded joint with considering Solid-state Phase Transformations

摘要

A computational approach based on thermal elastic plastic finite element method was developed for predicting welding residual stress with considering solid-state phase transformation. In this approach, the JMAK equation was used to simulate the formation of diffusive phase transformation, and the K-M relationship was employed to model the austenite-martensite change. Meanwhile, the additive rule based on phase fractions was adopted to describe the variations of mechanical properties such as yield strength and thermal expansion coefficient during the welding thermal cycles. Using the developed approach, welding residual stress distribution in a 2.25Cr-1Mo steel plate joint was computed. Based on the simulation results, the influences of solid-state phase transformation were discussed.