The sintered compacts of Ni
3Al intermetallic compounds(Ni-25Al, Ni-24Al and Ni-23Al(at.%))with high density (more than 96%) could be obtained by powder injection molding(PIM)process, using Ni and NiAl(Ni-50Al)powders as the starting materials. The debound compacts were sintered at 1325 °C for 2 hours in vacuum(10
-2Pa order). The structures were single phase of γ' in the Ni-25Al and Ni-24Al compacts, while that was two phases of γ' and a small amount of γ in the Ni-23Al compact. Tensile tests were performed in air at room temperature, 200°C, 400°C, 600°C and 800°C. The resuls of tensile tests were summarized as follows.
(1) At room temperature, the yield stresses for all compacts were a little over 400MPa. On the other hand, both elongation to fracture and tensile strength increased with increasing Ni content. The most Ni-rich compact Ni-23Al showed the good tensile properties of 13% elongation and 850 MPa tensile strengh.
(2) The yield stresses for all compacts increased with increasing temperature up to 400°C. However, the elongations of them decreased at over 400°C. They all fractured in elastic regions at 600°C.
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