Microstructure and Mechanical Properties of Al Added Ni₃(Si,Ti) Intermetallic Thin Sheets

Abstract:

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.

• Periodical: Materials Science Forum (Volumes 654-656)
• Pages: 480-483
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.654-656.480
• Online since: June 2010
• Authors: Yasuyuki Kaneno, Yasunori Fujimoto, Takayuki Takasugi
• Keywords: Cold Rolling, Microstructure, Ordered Intermetallic, Tensile Properties, Workability

References

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[3] Y. Fujimoto, Y. Kaneno and T. Takasugi: Mater. Res. Soc. Symp. Proc. Vol. 1128 (2009), p. U05-31. Fig. 4 SEM fractography of the alloys (a) #A4, (b) #B4 and (c) the unalloyed Ni3(Si, Ti) sheets tensile-deformed at 873K. (a) (b) (c) 10µµµµm.