Studies in Lithium Oxide Systems: VII, Li ₂ O–B ₂ O ₂ –SiO ₂

Abstract

Phase relations in the system Li 2 O–B 2 O 3 –SiO 2 were studied by quenching and solid‐state reactions. No ternary compounds were detected in the portion of the system containing less than 53% Li 2 O. Compatibility triangles were formed from the binary borate and silicate compounds. Liquidus data obtained by quenching are reported for four joins, Li 2 O·2SiO 2 –Li 2 O·2B 2 O 3 , Li 2 O·SiO 2 ‐Li 2 O·2B 2 O 3 , Li 2 O·SiO 2 ‐Li 2 O·B 2 O 3 , and Li 2 O·2B 2 O 3 ‐SiO 2 . The last join cuts across the two‐liquid region and is not a true binary system. Some probable ternary invariant points were located in the portion of the system which was quenchable to glass and adjacent to the two‐liquid region. Further data on the previously reported immiscible liquid formation are given and the significance is discussed. Data on the thermal expansion behavior of certain glasses are presented.