Abstract:Thin-wall samples of Ti-22Al-25Nb alloy are prepared through the laser additive manufacturing process.
The macro morphology, phase composition and microstructure for as-deposited and heat-treated samples are investigated.
In addition, the microstructure and room tensile properties of Ti-22Al-25Nb alloy are analyzed after a series of heat
treatments. The results indicate that for the as-deposited sample, the phase transforms as B2+O+α2→B2+O→B2 along the
build-up direction, while the phase composition and microstructure of heat-treated sample become homogeneous, which
is composed of B2, O and α2 phases. After solution treatment of 930℃ ×2h/air cooling followed by aging treatment of
800℃ × 24h/air cooling, the laser additive manufactured Ti2AlNb alloy shows better tensile properties with ultimate tensile
strength of 1017 MPa and elongation of 6.0%.