Strong bimetallic structural material alloyed with nitrogen

Abstract

The production of strong two-layer steel sheet—a bimetallic structure with a basic layer of low-carbon manganese microalloyed bainitic steel and an applied layer of two-phase austenite–ferrite stainless steel alloyed with nitrogen—is considered. In trials, the production of bimetallic material on the basis of the electrical-arc surfacing is investigated: specifically, the application of high-alloy steel to a plane microalloyed steel blank, by means of welding wire (under a flux layer), with subsequent hot deformation. The trials include the simulation of forced sheet cooling on the exit conveyer of the broad-strip mill and slow cooling of the final coiled strip. The microstructure, mechanical strength, and corrosion resistance of the bimetallic structural material are investigated. The proposed material matches the corrosion resistance of existing bimetals. Its yield point and the adhesive strength of the two layers exceed those of traditional two-layer steel by at least 30–50% and are three times the standard requirements.