Abstract
The equilibrium diagram of the binary systems, titanium-oxygen and titanium-carbon have been thoroughly investigated by the present authors. Following these investigations, the ternary equiliblium diagram of titanium-oxygen-carbon system has been studied similarly. In this ternary system, there exist the following solid phases; α-titanium, β-titanium, carbon, δ(TiC-TiO), ε(Ti2O3), and η(TiO2).
The α-phase containing about 10% oxygen dissolves about 1.5% of carbon as its solid solution, and the β-phase is considered to be produced at the titanium rich side of this ternary system by a ternary peritectic reaction; Liquid+δ(TiC-TiO)+α(Ti,O,C)\
ightleftarrowsβ(Ti,O,C) and the β-phase exists at the temperature higher than the transformation temperature α\
ightleftarrowsβ of titanium at 885°. The δ-phase is a continuous solid solution of NaCl type cubic stracture, and existing in the wide range of composition between TiC(δ) phase in the titanium-carbon binary system and TiO(δ) phase in the titanium-oxygen binary system. In this ternary system, three invariant reactions containing gaseous phases as; & Liquid + Graphite \
ightleftarrowsδ Phase + Vapour at about 3000°
& Liquid + ε phase \
ightleftarrowsδ phase + Vapour at about 1800°
& Liquid \
ightleftarrowsη phase + δ phase + Vapour at about 1670° are considered to exist.
