Studies of Annealing Process in Severely Cold Drawn Pearlitic Steel Wires

Abstract

The effects of spheroidizing annealing process on SWRH72B heavily cold drawn pearlite steel wires were studied and the mechanisms of low-temperature spheroidizing annealing were discussed. The results show that, with increasing drawing strain, the spheroidizing annealing temperature and time decreased and uniformity of the spheroidizing increased; the mechanism of low-temperature spheroidizing annealing was different from the traditional one of heavily cold drawn pearlite steel wires. When the true strains were between 2.85 and 5.1, the spheroidizing process of carbide could be divided into two stages: partial dissolution of lamellar carbide, and the precipitation and accumulation of compulsory dissolved cementite. When the true strains were larger than 5.1, the spheroidizing process of carbide was only characterized by precipitation and accumulation of compulsory dissolved cementite.