Mechanical and fatigue properties of stress relieved type 302 stainless steel wire

Abstract

Type 302 stainless steel wire is manufactured using a cold extrusion process. The cold working increases the ultimate strength of the wire from approximately 690 MPa to 2070 MPa. However, the cold working process creates residual stresses and surface microcracks in the wire. The residual stresses and microcracks reduce the fatigue life of the wire considerably. Elimination or minimization of residual stresses and microcracks is necessary if longer fatigue life is required. Residual stresses or microcracks in a wire can be minimized by a heat treatment process, which could improve both its mechanical properties and fatigue properties.