Theory of ultrathin films at metal-ceramic interfaces

TL;DR

This paper presents a theoretical model combining density functional theory and thermodynamics to understand ultrathin film formation at metal-ceramic interfaces, specifically applied to VC-doped WC-Co cemented carbides.

Contribution

It introduces a novel integrated theoretical approach to predict ultrathin film formation at interfaces in multicomponent systems, explaining VC's grain growth inhibition in WC-Co.

Findings

Ultrathin VC films are predicted to form at high temperatures in WC/Co interfaces.

The model explains the grain growth inhibiting effect of VC in WC-Co systems.

The approach combines interface energy calculations with thermodynamic modeling.

Abstract

A theoretical model for understanding the formation of interfacial thin films is presented, which combines density functional theory calculations for interface energies with thermodynamic modeling techniques for multicomponent bulk systems. The theory is applied to thin film formation in VC-doped WC-Co cemented carbides. It is predicted that ultrathin VC films may exist in WC/Co interfaces at the high temperature sintering conditions where most of the WC grain growth occurs, which provides an explanation of the grain growth inhibiting effect of VC additions in the WC-Co system.