Microstructure and Mechanical Properties of Al Added Ni3(Si,Ti) Intermetallic Thin Sheets
The effect of Al addition on microstructures and tensile properties of cold-rolled Ni3(Si,Ti) intermetallic alloys with L12 ordered structure, which were fabricated through thermomechanical processing from arc-melted ingots, were investigated. Addition of 4 and 8 at.% Al to Ni3(Si,Ti) was conducted in two ways that Al substituted for Ti site and both for Ni and Ti sites, respectively. The alloys made by the former way showed a two-phase microstructure consisting of disordered fcc Ni solid solution dispersions in the L12 matrix, irrespective of Al contents, while the 4 at.% Al alloy made by the latter way exhibited an L12 single-phase microstructure. These alloys were successfully cold-rolled to thin sheets with a thickness of 200 μm except the 8 at.% Al alloy made by the latter way. For the thermomechanically processed 4 at.% Al alloys, high-temperature yield stress was higher in the alloy made by the latter way than in the alloy made by the former one, suggesting that the single-phase microstructure consisting of whole L12 ordered structure is favorable for high-temperature tensile property.
Jian-Feng Nie and Allan Morton
Y. Kaneno et al., "Microstructure and Mechanical Properties of Al Added Ni3(Si,Ti) Intermetallic Thin Sheets", Materials Science Forum, Vols. 654-656, pp. 480-483, 2010