Effects of the nitrogen addition on high temperature tensile properties and
creep resistance of the fully lamellar and the duplex Ti-48.5Al-1.5Mo (at.
%) alloy were investigated. High temperature yield strength of the nitrogen
-doped alloys increased due to solute hardening and precipitation hardening
of Ti3AlN. Nitrogen addition led to remarkable improvement of creep resist
ance in the duplex microstructure as well as in the fully lamellar microstr
ucture. In particular, the primary creep deformation of the 1.0 at.% nitrog
en-doped alloy with the duplex microstructure decreased definitely to a sim
ilar or superior level of the fully lamellar alloy. We consider that precip
itate hardening of p-phase (Ti3AlN) and solute hardening of nitrogen atoms
may be responsible for such remarkable creep resistance of the nitrogen-dop
ed alloys. (C) 2000 Kluwer Academic Publishers.