The wettability at high temperatures in the technological development of materials

Reference Presenter Authors
14-061 Sebastiao Ribeiro Ribeiro, S.(Escola de Engenharia de Lorena);

Wettability is an important property of solid-liquid interface. Thermodynamically it is a solid-liquid-gas energies balance. The study of wettability is very important in several areas of technology, for instance, sintering of many ceramics materials or metals, production of materials by infiltration processes, corrosion behavior, brazing and so one. The wettability can be measured from low temperatures to very high temperatures, but this work will show a review using studies and results from high temperatures measurements. The main goal of this talk is to show a brief revision about works involving wettability applications in selecting additives for sintering via liquid phase, studies about prevision of corrosion in refractories at high temperatures and metal-ceramics composites or functional materials to work at high temperatures. Some examples are described as following: silicon carbide and oxides or oxides mixtures involving rare earths, silicon nitride wetted with Ti-Cu alloys, alumina with liquid aluminum, zirconia with metals, carbides with nickel or cobalt metals, some refractories and real or synthetic slags, and others examples. In these cases the temperatures varies from 1300°C to 1900°C and the method used to measure the contact angle was the sessile method.  The contact angle can vary from 5°, for liquids used to sintering covalent ceramics to 120° for graphite and liquid slags.