Effect of dilution on the microstructure and properties of CoCrMoSi alloy coatings processed on high-carbon substrate

Abstract

The Laves phase reinforced CoCrMoSi alloy system has emerged as a candidate material to protect the surface of components to withstand harsh environments under wear and/or corrosion. However, previous reports have raised some concerns and restricted a wider selection of iron-based substrates to be coated, especially limiting the carbon content. This work aims to outline the Laves - Carbides phases in the microstructure and its effect on the properties of T400 alloy deposited on GGG40 ductile iron. Dilution of 26 % ensured Laves formation either as primary or secondary, due to high-silicon substrate selected. Departing from 41 % dilution, the alloy changed to a completely carbide strengthened system. Therefore, for the lowest dilution the coatings hardness is dictated by Laves phase whereas, for higher ones, carbides are the most influent phases.