As the new generation of secondary metallurgy and advanced continuous casting technologies have been developed in the last decade, refractory materials have met the greatest challenge in order to secure the high metal quality under economical and ecological aspects. During service refractories must not only tolerate high temperature but also withstand stresses (thermal and/or mechanical) as well as resist combined attacks by liquids such as molten metals, slags and fluxes. Especially in near net shape casting technologies enhanced corrosion and erosion performance is required followed by thin wall thickness design of functional components such as submerged entry nozzles /1/, /2/. Corrosion of refractories by molten liquids involves reactant contact enabling the reaction to take place and product transport to allow it to proceed it. The wettability of refractories against metal- and metal/slag- melts affects greatly the corrosion, erosion and clogging behaviour /3/. The change of the contact angle (wetting angle) as a function of time up to a constant value observed in so called hot stage microscopes due to the sessile drop method is of great technological importance and especially in the beginning of casting.
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