REDUCING METHOD FOR RESIDUAL STRESS AT WELDED JOINT OF STEEL

摘要

PURPOSE:To reduce the residual stress at the welded joint without depending on the heat treatment, by welding at least the final layer of the deposited metal using an austenitic metal, and after that, by cooling to a temperature under the Ms point for causing the martensitic transformation. CONSTITUTION:At least the final layer of the deposited metal of the welded joint is welded with an austenitic metal, and is cooled to a temperature under the starting point of the martensitic transformation (Ms point) for the purpose of causing the martensitic transformation in the welded final layer; hereby, the shrinkage of the deposited metal is canceled by the expansion due to the transformation from the austenite into the martensite. Accordingly, the residual stress at the weld zone is reduced, so that such difficulty as the embrittlement to be accompanied by the heat treatment is dissolved, and the welded joint with good properties can be obtained.