TiAl-BASED ALLOY, PROCESS FOR PRODUCING SAME, AND ROTOR BLADE USING SAME

摘要

A hot-forged TiAl-based alloy having excellent oxidation resistance and high strength at high temperatures, and a process for producing such an alloy. A TiAl-based alloy comprising Al: (40+a) atomic % and Nb: b atomic %, with the remainder being Ti and unavoidable impurities, wherein a and b satisfy formulas (1) and (2) below. 0≦̸a≦̸2  (1) 3+a≦̸b≦̸7+a  (2) Also, a TiAl-based alloy comprising Al: (40+a) atomic % and Nb: b atomic %, and further comprising one or more elements selected from the group consisting of V: c atomic %, Cr: d atomic % and Mo: e atomic %, with the remainder being Ti and unavoidable impurities, wherein a to e satisfy formulas (3) to (9) shown below. 0≦̸a≦̸2  (3) 3+a≦̸b+1.0c+1.8d+3.8e≦̸7+a  (4) b≧2  (5) c≧0  (6) d≧0  (7) e≧0  (8) c+d+e>0  (9)