Effects of Carbon and Molybdenum on Mechanical and Hot Wear Properties of Multi-component White Cast Irons for Steel Rolling Mill Roll

Abstract

Multi-component white cast irons containing carbide-forming elements such as Cr ， Mo ， W and V have been widely popularized as ro11 materials for hot rolling mills because of their excellent performance. In this research ， influence of C and Mo contents on mechanical properties ， hot wear properties and their cor. relation were investigated using Fe-5%Cr-5%W -5%V -5%Co-Mo-C (mass%) cast a11oys. Cast irons with M 2 C eutectic carbides and martensitic matrix were obtained in a wide range of Mo contents above 2.5 mass%. Micro 一 hardnessin such martensitic matrices showed over 600 HV ， and macro-hardness showed similar tendency to matrix hardness. Tensile strength ， compressive 0.2% proof strength ， and frac. ture toughness were found to be high in cast irons with high hardness ， but they were decreased in cast irons with excessive carbide conten t. It was found that wear resistance was greater in cast irons with high Mo content which show high hardness and high fracture toughness.