3-REGIONS IN THE POWER-LAW CREEP REGIME OF TIAL

Three regions in the power-law creep regime have been recognized on the creep features of polycrystalline single-phase TiAl intermetallics at 1100 K under 63 approximately 400 MPa. In each region, creep curves show a distinctive type. The parameters which indicate the effects of composition, grain size, stress and temperature on the minimum creep rate also have characteristic values in each stress range. The deformation process in the high stress range is necklace-type dynamic recrystallization. Deformation processes operating in the intermediate- and low-stress ranges remain to be specified.