RELIEVING METHOD FOR RESIDUAL STRESS OF WELDED PRODUCT MADE OF AUSTENITE STAINLESS STEEL

摘要

PURPOSE:To economically relieve the residual stress of a welded product made of austenite stainless steel by heating and keeping the product at a relatively low temp. and rapidly cooling it to superpose residual stress due to heat deformation on the residual stress due to welding. CONSTITUTION:The whole of a welded product made of austenite stainless steel or its weld zone is heated to a temp. as high as possible within a range below a temp. at which carbide begins to precipitate remarkably, i.e. to 350-550 deg.C, and it is kept at the temp. for a prescribed time in accordance with the thickness. The welded product is then water cooled from the temp. or rapidly cooled at a cooling rate almost equal to or higher than that of the water cooling to produce compression side residual stress at the outside of the produce and tension side residual stress at the central part by a temp. difference in the through thickness direction at the time of the cooling. The stresses are superposed on the residual stress distribution of the welded product to relieve the residual stress of the product.