Published online by Cambridge University Press: 28 February 2011
A Ni3AI + B base composition and derivatives containing Hf, Zr, Nb, or Nb + Hf substitutions for Al were processed by powder metallurgy, consolidated by compaction + extrusion, and evaluated for mechanical properties. The mechanical property evaluation consisted of tensile tests performed in air and vacuum, and fatigue crack growth tests performed in air. Microstructures, test specimen fracture morphologies, and tensile and fatigue deformation features were also studied. Some of the substitutions improved certain properties, but none improved ductility. The discussion considers property-fracture morphology-deformation structure relationships.