The Research On Microstructures And Properties Of The High Alloy White Cast Iron Used In Grinding Ball

The article on the basis of analyzing the latest research of grinding ball and the condition of the grinding ball used in molybdenum mineral joins the right amount copper and vanadium in the high chromium white cast iron prepares the high alloy white cast iron. The paper is study the effects of structure and property of the modification and heat treatment of the high alloy white cast iron grinding ball by means of adding the modification agent RE and RE-B. The article studies the effects of RE, RE-B, cooling ways and tempering temperature on structure, toughness, hardness and abrasion corrosion resistance of high alloy white cast iron using the metallographic microscope, scanning electron microscope(SEM), X-ray diffractometer spectrum(XRD), hammer impact machine, hardness measure apparatus and three body grinding compound abrasion testing machine.The chemical composition selected ultimately of the high alloy white cast iron: chromium12.0%, carbon2.6%,copper1.0%,vanadium1.0%,silicon1.0%,manganese0.7%, sulphur and phosphorus<0.05%, modification agent RE0.6%-B0.05%. The research results show that the structure, hardness, toughness and abrasion corrosion resistance of high alloy white cast iron can improve by uses RE, RE-B modification. When RE joins 0.9%, the modification effect is fine and the carbide lattice separation and nubbin form. The carbide lattice separates completely, the hardness, toughness and abrasion corrosion resistance are ideal when adding RE is 0.6% and that of adding B is 0.05%. The impact toughness and hardness of the alloy can enhance with different quenching medium. When the alloy air cooled, its impact toughness and hardness are good, but the abrasion corrosion resistance is worse than the sodium silicate quenching. The toughness of the alloy can enhance in different temperature tempering. The matrix disseminates the distribution massive tiny secondary carbides and the properties are best in 400℃tempering. The alloy best quenches the tempering craft for 980℃×2h air cooled and 400℃×3h air cooled may obtain the best hardness, toughness and the abrasion corrosion resistance.