Durable phosphate glasses with lower transition temperatures

A composition study was used in the present work to find an easily fabricated phosphate glass with a suitable glass transition temperature for simple annealing and the production of molded phosphate optics, which would be more durable than traditional phosphates with low transition temperatures. Glasses were characterized for hardness, transition temperature, and chemical durability. An interesting composition with small amounts of tin oxide, alumina, and borate, with a decreased amount of P2O5 was found to have increased durability (in comparison to an old phosphate composition) with a glass transition temperature in an acceptable range for melting and molding. Future work could include further composition improvement to increase durability and lower transition temperature and doping with rare-earth ions to study their electro-optical effects in the glass.