抄録
The structures of Ti-4∼14% Al-2∼8% Co alloys have been examined by optical microscopy, after annealing for a long period in the range of 600°∼1100°C. A partial titanium-aluminium-vanadium ternary diagram for this range has been established.
To distinguish the α and α2 phases, use was made of the fact that no precipitation from α2 occurs with decreasing temperature, but α2 is precipitated from α in the high aluminium alloys.
Ti-6% Al-4% V alloy is situated on the boundary for the formation of the α2 phase. The increase of aluminium or vanadium contents in this alloy brings about the formation of the α2 phase.
