Surface Tension and Wettability Between Silicon Nitride of RE2O3-MgO-SiO2 (RE=Y, Gd, Nd and La) Melts

The effect of RE2O3 (RE=Y, Gd, Nd, and La) additives on the surface tension of 45.2MgO-54.8SiO2 (mol%) melts have been investigated using the ring (detachment or maximum pull) method. Furthermore, the wettability of RE2O3-MgO-SiO2 melts between the silicon nitride polycrystalline substrate is determined using the sessile drop method. The surface tension of RE2O3-MgO-SiO2 melts were found to increase with the content of any rare-earth additions, which suggests that a rare-earth oxide behaves as a network modifier of the complex silicate anions in high temperature melts. The surface tension increased in the order of the cationic radius of rare-earth oxides as follows: Y2O3More