Deformation behavior of a Ni−30Al−20Fe−0.05Zr intermetallic alloy in the temperature range 300 to 1300 K

摘要: The deformation behavior of an extruded Ni-30 (at. pct) Al−20Fe−0.05Zr intermetallic alloy was studied in the temperature range 300 to 1300 K under initial tensile strain rates varying between about 10−6 and 2×10−3 s−1 constant load compression creep 1073 K. microstructures fractured specimens were characterized by transmission electron microscopy (TEM). Three regimes observed: Region I consisted athermal regime low ductility (less than 0.3 occurring 400 673 K, where substructure slip bands a few grains. Exponential dominant region II changed from mixture dislocation tangles, loops, dipoles at microstructure consisting subgrains tangles 973 generally 2.0 2.5 pct below 980 this region. A significant improvement observed III, which occurred An analysis data suggests that viscous glide with stress exponent,n, 3 high-temperature climb withn≈4.5 two mechanisms depending on temperature. average activation energy for 310±30 kJ mol−1 both processes. In case, transition when σ/E<1.7×10−4, σ is applied andE Young’s modulus.