Study on the making and heat treatment of some advanced high-strength steels

Abstract

This paper presents the results of a research on the technology of producing some advanced high-strength steels (AHSS) in Vietnam from sponge iron (DRI) of MIREX. Sponge iron which has low C, P, S contents has not been widely used in Vietnam yet. This research, initially, has solved the technology of making the carbon steels and alloys from sponge iron in the induction furnace with the capacity of 10 tons. Some AHSS billets, made from DRI, which have special mechanical properties such as S10C, DP800, and TRIP800 steels have been studied thanks to the integration of such technologies as refining and making, deformation, and heat treatment for the CMnSi steel group. The resulted steels have good mechanical properties, both high durability and plasticity, even better than that of high-strength low alloy (HSLA) steel (CMnSi stell). In particular, the S10C-M deep-drawing steel has been tested in two military plants and shown the satisfaction of technical requirements.