Improving the wear resistance of high chromium cast iron through high entropy alloys concepts and microstructure refinement

Abstract

High Chromium Cast Iron (HCCI) has demonstrated its effectiveness as a potential material for applications in severe environments due to its remarkable wear resistance attributed to the volumetric fraction of carbides in the microstructure. This study investigates a novel high-alloyed composition of white cast iron named High Entropy White Cast Iron (HEWCI), which merges the concepts of HCCI and high entropy alloys. Specifically designed chemical compositions incorporating Vanadium (V), Molybdenum (Mo), and Nickel (Ni) were employed to enhance its wear resistance properties. The solidification path, microstructural characterization, and wear responses of HEWCI were evaluated. XRD and SEM techniques were carried out for characterization purposes. Linearly reciprocating ball-on-flat sliding wear tests were conducted using a high-frequency reciprocation rig (HFRR) tribometer, assessing wear volume, linear wear rate, specific wear rate (κ), and coefficient of friction (COF). The results revealed microstructural refinement and precipitation of new carbides through V, Ni, and Mo additions. This approach demonstrates that adding carbide-forming elements and refining the microstructure are promising strategies for enhancing wear performance in HEWCI alloys.