NITROGEN DISSOLUTION IN PHOSPHATE-GLASSES CONTAINING M(2)O, MO AND M(2)O(3)

Phosphorus oxynitride glasses containing M(2)O, MO and M(2)O(3) were p repared by melting in dry ammonia. The glass composition and the water content in the furnace atmosphere were factors controlling the maximu m nitrogen dissolution in a phosphate glass. For the same cation conce ntration in a phosphate glass the amount of nitrogen that could be dis solved decreased with increasing cation valence. Other properties eval uated included the thermal expansion coefficient and the dissolution r ate in water.