Work Hardening and Flow Softening of γ-TiAl Containing Ni
This paper presents the true stress - strain curves and data analyses of a Ni-containing TiAl and its reference alloy based on the isothermal compression tests at 1000°C and 0.01 - 1.0s-1 strain rates. The results show that the minor Ni addition makes the flow softening coming sooner and therefore significantly lowers the peak stress. Those effects, in addition with a better balance between the work hardening and flow softening during hot deformation, improve the steady state flow behavior of TiAl. The Ni-influence mechanisms are also suggested based on the TEM observation of dislocation configurations and lamellar breakdown during the deformation.
S.-G. Kang and T. Kobayashi
J. H. Zhang et al., "Work Hardening and Flow Softening of γ-TiAl Containing Ni", Materials Science Forum, Vols. 449-452, pp. 833-836, 2004