Abstract:In the present study, V-shaped arc welding of the AISI 1045 steel is modeled by using 2D Finite Element Model (FEM). The temperature distribution, microstructure, grain growth, and the hardness of the heat-affected zone (HAZ) of the welding are simulated. The experimental work is carried out to validate the FE model. The very close agreement between the simulation and experimental results show that the FE model is very effective for predicting the microstructure, the phase transformation, the grain growth and the hardness. The effect of preheat temperature on the martensite formation is analysed, and it is shown that 225 • C preheating completely eliminates the martensite formations for the 12 mm thick plate.