METHOD FOR MANUFACTURING HIGH-STRENGTH STEEL SHEET PARTS SUBJECT IN USE TO FATIGUE STRESSES

摘要

The manufacturing method comprises the steps of: carrying out one or more forming operations so as to give the desired geometry to the part; and subjecting the part thus formed to a single heat treatment having only a stress relieving treatment, which is preferably carried out at a temperature in the range from 530° C. to 580° C. for a time in the interval from 45 to 60 minutes and is followed by cooling of the part in air. By virtue of the formed part being subjected to a stress relieving heat treatment, the residual stress state due to the initial forming process and to the bead welding, if any, is eliminated or at least significantly reduced.