Penetration and dissolution mechanisms are phase (which is the first to be penetrated by liquid), reviewed for predominantly single phase oxide, two phase oxide, and oxide-carbon composite and the characteristics of melt and reaction products refractories by liquid silicates. Theoretical models affect the rate of the reaction. Consequently, to underof these processes, as well as static (sessile drop, stand the corrosion mechanisms, refractories microdipping, and crucible) and dynamic (rotating finger structures (in particular, composition and texture of and rotary slag) experimental tests, along with grain and bond phases, the linkage of grain to bond, their practical limitations are considered. Direct and internal or residual stress), melt properties (congruent or homogeneous) attack involves (especially composition and viscosity as a function of dissolution of a solid into a liquid with no temperature), and their wetting and interaction at intermediate solid phase leading to active high temperatures should be examined together. corrosion. Indirect (incongruent or heterogeneous) Almost all liquid metals do not wet ceramics while attack leads to formation of one or more new solid phases at the original solid/liquid interface. This almost all slags, glasses, and fluxes do, so attack at may lead to passive corrosion. Examples of direct the slag line, where the less dense (typically silicate) and indirect attack in a range of refractory-liquid liquid floats on the denser metal liquid, is frequently systems are described highlighting the critical a problem. Carbon based ceramics are not wetted by influence of the composition and hence viscosity silicate liquids, behaviour which has led to their of the local liquid adjacent to the solid. Penetration extensive use in iron-and steelmaking refractories.
and corrosion can be controlled either through the Wetting behaviour gives an indication of penetration local liquid composition via the refractory or the (simple permeation via open porosity without chemibulk liquid or by microstructural control of the cal reaction) but not attack or corrosion (penetration refractory by, for example, internal generation of and chemical reaction). This review begins by examindense layers or external deposition/generation of passive coatings. IMR/325 ing simple theoretical treatments of these phenomena. Much research has examined refractories in different