Development of Fine‐Grained High‐Carbon Steel in High Reduction Low Temperature Rolling

Abstract

AbstractAfter blanking and bending to form parts with the desired shape, high‐carbon steels are quenched and tempered to produce various machine parts. Thus, the spheroidization, formability and hardenability are very important properties for high‐carbon steels. Thermo‐Mechanical control Process of rolling has been widely used in the steel industry. However, it is difficult to apply this process to high‐carbon steels because of the heavy rolling load. Thus, fine‐grained high‐carbon hot strips were developed through high‐reduction and low‐temperature rolling by using single roll rolling mills with different diameters and laminar flow cooling devices in the finishing train, the grain size of these steels was about 3 microns. Also developed annealed strips with fine homogeneously dispersed spheroidal cementite had many excellent characteristics. For example, burring formability investigated by the hole‐expanding and surface hardness evaluated by laser hardening of the developed high‐carbon annealed steels, were excellent.