Optimization of Spheroidizing Annealling Process in Dual-phase Region of 80WVRe Steel Wire

Adopting orthogonal test to research the spheroidizing annealling process in dual-phase region of cold drawn 80WVRe steel wire. The results show, austenizing temperature, isothermal time, isothermal temperature and holding time had almost equivalence effects on hardness of 3.39 mm steel wire, while isothermal time had an obviously larger effect on hardness of 1.91 mm steel wire than the another three factors. The optimal spheroidizing annealing process of 3.39 mm steel wires was as follows: with austenizing temperature 760 ℃, holding time 60 min, isothermal temperature 690 ℃, isothermal time 360 min, uniformity and roundness of granule carbonization were improved markedly and hardness of the steel wire was 175 HV0.5. The optimal spheroidizing annealing process of 1.91mm steel wires was as follows: with austenizing temperature 760 ℃, holding time 90 min, isothermal temperature 690 ℃, isothermal time 240 min, uniformity and roundness of granule carbonization were improved markedly and hardness of the steel wire was 177 HV0.2.