Wire rod of boron-bearing low-carbon steel for direct deep drawing

Abstract

The Moldavian Metallurgical Plant has developed an integrated technology for making steel, a continous-cast semifinished product, and wire rod in accordance with the requirements of international standards. The technology involves optimizing the chemical composition of the steel (normalizing the contents of the chemical elements and the carbon equivalent C e , inoculating the steel with calcium to lower its content of nonmetallic inclusions, and microalloying it with boron) and using efficient regimes for rolling and two-stage cooling (thermomechanical treatment) of the wire rod on a Stelmore line. The low-carbon wire rod is easily cleaned of scale by mechanical or chemical means and can be reduced from 5.5 to 0.5 mm in diameter by drawing at speeds up to 30 m/sec without an intermediate heat treatment to soften the wire rod/wire.