Oxide glass processing in space

The experimental work performed thus far has resulted in the preparation of new glass compositions not reported heretofore in the open literature. Recent experiments which have resulted in the formation of 1/4-inch-diameter glass samples from two compositions, suggest that containerless melting and cooling as envisioned for space operations is of real technological significance. To date studies of space glasses have by choice been confined to oxide glasses only. It is felt that the applications for such glasses are more readily predictable than for the other materials, and that many of the principles that will evolve from a study of oxide glasses, which can be melted in air, permit a more direct approach to non-oxide materials in the future. The compositions being studied are all very simple in terms of traditional glass practices, none of them containing more than three major constituents. Future efforts should be concerned with more complex compositions, both to cover a broader range of optical properties and to enhance glass-forming tendencies.