Precipitation of molybdenum carbide in steel: multicomponent diffusion and multicomponent capillary effects

Alloy carbides are of considerable importance in the design of steels resistant to creep deformation during service at elevated temperatures. Their formation in ternary or higher order steels involves the diffusion of both substitutional and interstitial solutes. Because these solutes diffuse at vastly different rates, there are difficulties in adopting the theory for diffusion controlled growth in binary alloys. The present work presents a method, de:eloped in the context of molybdenum carbine precipitation in steels, for modelling growth With local equilibrium at the interface while at the same time accounting for capillarity effects. The theory is tested against published expelimental data.