The effect of cold work and heat treatment on the fatigue behaviour of 3CR12 corrosion resistant steel wire

The fatigue behaviour of 3CR12 corrosion resistant steel wires has been investigated as a function of combined effects of heat treatment, such as annealing, quenching as well as mechanical treatments, such as a cold drawing. The samples were heat-treated, cold drawn and subjected to fatigue testing under load control mode. The results obtained for cold drawn 3CR12 steel wires having initial annealed microstructure, showed that the drawing strain increases both static mechanical properties and fatigue limit. Further drawing above 0.47 strain does not increase the fatigue strength significantly. However, an application of quenching treatment followed by cold drawing, improves the fatigue limit more significantly than in case where the 3CR12 steel was annealed and cold drawn. Dual-phase microstructure obtained by quenching treatment acts beneficially in terms of delaying fatigue crack initiation and propagation processes and most importantly, a notch effect on the fatigue behaviour of 3CR12 steel wires treated in this way become insignificant.