Hot tensile properties and deformation response of a gamma/Ni/-gamma prime/Ni3Al/-delta/Ni3Nb/ eutectic compositeThree distinct regions of tensile, deformation and fracture behavior were observed in a 2.5 wt. per cent Al gamma/gamma prime-delta eutectic alloy as the testing temperature was varied. The major finding was an extraordinary ductility maximum at about 550 C. It was shown that this phenomenon is caused by the deflection of transverse cracks at the eutectic grain boundaries when yielding occurs. This delamination between eutectics grains caused by fracture of a gamma prime eutectic grain boundary film leads to a distinctly different 'wood-like' fracture surface morphology. Above 690 C to 926 C, yield and tensile strength values decrease while ductility increase slightly. Cooperative twinning of both phases develops giving rise to block-like deformation of the microstructure quite in parallel to the behavior observed previously in the gamma-delta system.
Document ID
19760045064
Acquisition Source
Legacy CDMS
Document Type
Conference Paper
Authors
Bertorello, H. R. (Cordoba, Universidad Nacional, Cordoba, Argentina)
Hertzberg, R. W. (Cordoba National Univ. Argentina)
Kraft, R. W. (Lehigh University Bethlehem, Pa., United States)