CORRELATIONS FOR THE THERMAL-EXPANSION COEFFICIENTS OF MOLTEN GLASS-FORMING SYSTEMS

The specific volumes of molten Pd40Ni40P20, Pd77Cu6.5Si16.5, Pd82Si18, and Ni80P20, which are all glass formers, and were measured near the liquidus. It was found that the ratio alpha/T-g, where alpha is the thermal expansion coefficient and T-g is the glass transition temperature, remains fairly constant for all these systems. The scaling follows from the fact that with a larger thermal expansion coefficient, the free volume of the molten system would be squeezed out faster resulting in a larger T-g. This scaling behavior also allows us to roughly predict the glass transition temperature of a glass forming system. The glass forming ability can also be predicted by a parameter defined as alpha/T-1. (C) 1995 American Institute of Physics.