Mass transport phenomena at the liquid metal/substrate (metal, carbide) interface

Abstract We have developed a model that describes surface mass transport in dissimilar materials such as liquid metal/substrate (metal, structural ceramic) and verified the model with experimental data taken from the literature and generated in our research on liquid aluminum and silicon carbide at 933 and 1253 K. Knowing the size of contact angles of drops on substrates as a function of time and temperature in a controlled atmosphere allows the calculation of apparent surface diffusion coefficients that are characteristic of the systems under consideration. Apparent surface diffusion appear to be two components related to adhesional wetting (physical effect), D s , and reactive wetting (chemical effect), D r , and can be expressed by the following equation: D s + D r = (γ LV / η) cos π e λLT = constant, where γ LV and η are the surface tension and viscosity of the liquid, respectively; λ is a geometrical roughness of the solid surface; and π e is a contact angle at equilibrium.