Computer Aided Interfacial Measurements

The sessile drop profile method was combined with X-ray radiography to develop a precise method to measure interfacial tensions and contact angles of liquid metals at high temperatures and in a variety of atmospheres. An accurate method of digital image processing was developed to capture, enhance and determine the coordinates of the X-ray shadow image of the droplet. Laplace's equation was then solved numerically to allow a non-subjective determination of interfacial tension and contact angles. Examples of the determination of the interfacial tension of mercury in argon, of liquid iron at 1 550°C under various CO/CO2 gas mixtures, of iron carbon alloys and of liquid iron in contact with a lime-alumina-silica slag at 1 550°C, are given.