Wetting and Spreading Kinetics between Liquid CaO–SiO₂ Slags and a Solid SiO₂

Abstract

Wetting and spreading phenomena between SiO 2 single crystal and CaO-SiO 2 slags with difference composition; SiO 2 saturated and non-saturated slags at 1 600°C were investigated by using the dispensed drop technique (DDT) with a high-speed camera (1 000 frames/s). The apparent contact angle and height of non-saturated slag were significantly smaller than those of saturated slag. The apparent radii of saturated and non-saturated slags were significantly different after 0.01 s. The change in the apparent volume of the slags was analyzed by using a spherical cap model. The apparent volume of the saturated slag was constant, but that of the non-saturated slag decreased because of film type spreading. After quenching, the film type spreading was verified, and a dissolution reaction occurred in the non-saturated slag, whereas no such phenomena were observed in the saturated slag. For the saturated slag, the spreading kinetics fit well with the non-reactive viscous model suggested by a previous study. However, nonsaturated slag could not be applied to spreading kinetics due to the film type spreading.