Finite-element Simulation of Low-alloy High Strength Steel Welding Incorporating Improved Martensite Transformation Kinetics and Recrystalization Annealing

Abstract

An experimental and numerical investigation was conducted to study the continuous cooling transformation kinetics for the welding simulation of low-alloy steels. A modified Koistinen-Marburger (K-M) equation was proposed based on the transformation kinetics characteristic of low-alloy steels. The modified K-M equation was proved to be more accurate in predicting the stress evolution of low-alloy by a cyclic uniaxial test. Finite-element simulation of Weldox960 steel welding incorporating the improved martensite transformation kinetics and recrystallization annealing was performed to predict the stress evolution and residual stress. The simulation results indicated that the transformation kinetic equations and the recrystalization annealing both had non-ignorable effects on the stress evolution. In addition, the simulated residual stress based on the modified K-M equation and annealing model compared well with the data measured by the hole drilling method.