Effect of feeding Ca–Mg–RE–Zr composite cored wire during refining of liquid steel on abrasive wear resistance of high-strength steels

Abstract

The abrasive wear performance of high-strength steels was evaluated by two kinds of designed laboratory test methods, i.e. the sliding abrasion test and the stirring wear test. Optical microscopy and scanning electron microscopy were utilized to observe the worn surfaces, microstructures and inclusions. The tested results show that the feeding of a small amount (1.5kg/t) of Ca–Mg–RE–Zr (RE, Rare Earth) composite cored wire replacing 0.31 (wt%) expensive Ni in the steels resulted in better mechanical properties and much better abrasive wear performance, which was attributed to the modification of inclusions and improvement of impact toughness by the addition of Ca–Mg–RE–Zr composite cored wire. Microcutting, microploughing and scratching were the main wear mechanisms in abrasive wear tests. The abrasive loss of high-strength steels was larger in the wet wear condition than that in the dry wear condition in the sliding abrasion test, which was caused by the increasing corrosion wear and reducing debris accumulation.