Abstract: The effects of the deformation in the molten – weld pool and the solidification shrinkage on the stress – strain fields in the trail of molten – weld pool are revealed. As a result, a numerical model for simulation of stress – strain distributions of welding solidification crack is developed. On the basis of the model. The thesis simulated the driving force of solidification crack of stainless steels, that is, stress-strain field in the trail of molten weld pool. Firstly, the effect of the deformation in the molten – weld pool eliminated after the element rebirth method is adopted. Secondly, the influence of solidification shrinkage is considered by increasing thermal expansion coefficients of the steels at elevated temperature. Finally, the stress – strain fields on different conditions are calculated.

Key words: Driving force, Numerical simulation, Stress – strain field, Welding solidification crack