Microstructural Investigation on Heat Treatment of Hypoeutectic High Chromium White Cast Irons

Abstract

High chromium white cast irons (HCWCI) are widely used as abrasion resistant materials in cement manufacturing, mineral processing and slurry pumping industries. Their high resistance to wear in these demanding situations stems from the presence of hard eutectic (Cr, Fe)7C3 carbides in their microstructures. In this context, the properties of hypoeutectic iron of HCWCI containing 25 wt. %Cr-2.5 wt. %C were investigated after destabilisation heat treatments, cooling (slow and fast cooling) to ambient temperatures, their influence on the microstructure was investigated. For characterization of the hypoeutectic iron of HCWCI, several experimental tests were performed using the following laboratory equipment: Light optical microscope, scanning electron microscope. The amount of retained austenite also depends on the alloying additions in the melt during melting processes, destabilisation temperatures, soaking time and the cooling rates during heat treatment processes.