METHOD FOR REDUCING RESIDUAL STRESS IN TWO-PHASE STAINLESS STEEL STRUCTURE

摘要

PURPOSE:To reduce the residual stress in a two-phase stainless steel structure by heating and holding the structure at a specified temp. and rapidly cooling it to inhibit embrittlement. CONSTITUTION:A two-phase stainless steel structure is heated to 500-650 deg.C between the temp. range in which carbides and sigma-phase are precipitated and the temp. range in which embrittlement is caused and the heated structure is held at the temp. for a limited time to inhibit embrittlement caused at about 450 deg.C and to reduce the residual stress. The held structure is rapidly cooled from the temp. to inhibit embrittlement due to brittleness at 457 deg.C. This method is effective in reducing residual stress produced in a cast monolithic structure during soln. heat treatment, welding or bending.