Quantitative microanalysis of carbide/carbide interfaces in WC–Co-base cemented carbides

TLDR: Carbide/carbide boundaries in WC-Co-base cemented carbides containing 6-20 wt-%Co were studied with two high resolution microanalytical techniques: atom probe field ion microscopy and analytical transmission electron microscopy as discussed by the authors.

Abstract: Carbide/carbide boundaries in WC–Co-base cemented carbides containing 6–20 wt-%Co were studied with two high resolution microanalytical techniques: atom probe field ion microscopy and analytical transmission electron microscopy. All boundaries studied, i.e. WC/WC boundaries and, in materials containing cubic carbides (γ-phase), WC/γ and γ/γ boundaries, were found to contain about half a monolayer of cobalt, localized to a zone of monolayer thickness. The carbide/carbide boundaries may thus be described as grain (phase) boundaries to which cobalt has segregated. The carbide skeleton model for WC–Co is thereby confirmed. In WC–Co materials which contain Cr3C2 as a grain growth inhibitor, chromium segregates to WC grain boundaries.MST/354