HIGH-MODULUS GLASSES BASED ON CERAMIC OXIDES.

Abstract : An investigation was conducted of glass formation among alumina-base oxide compositions. Modulus measurements were made on those compositions which formed glasses to determine the influence of compositional variations on elastic properties. It was found that the presence of Cao and a small amount (< 10 percent) of Sio2 as components was necessary for good glass formation. Among other components considered, Li2o and Mgo had the greatest effect on increasing the specific and absolute modulus, respectively. In analyzing the dependence of modulus on composition, a useful correlation between Young's modulus and the 'true ionic volume fraction' was found with which certain predictions could be made concerning the effect of various components on modulus. The most promising glass found was one containing Mgo (Glass R105). This glass has a modulus of 16 million psi, a specific modulus of 5.5 million psi and a specific gravity of 2.9. Strength, static fatigue, water durability, devitrification temperature, fiberizability, and reactivity with potential container and bushing materials were also evaluated for this glass. (Author)