Preparation of Dense Ultrafine TiAl Alloys by Spark Plasma Synthesis from Mechanically Activated Powders

Abstract:

Powder of Ti-46at%Al alloy was synthesized through mechanical activation (MA) and then sintered and concurrently consolidated in a short sintering time of 900 s by using spark plasma sintering (SPS) process. The XRD and SEM profiles show that the microstructures of TiAl alloys contained γ TiAl and small amount α-2 Ti3Al phase, whose amount can be controlled by the sintering temperature. The compacts retained the original fine-grained fully densified bodies by avoiding an excessively high sintering temperature. The alloys sintered at higher temperature with this process showed a coarser microstructure. So it is possible to produce dense nanostructured TiAl alloys by mechanically activated spark plasma sintering (MASPS) within a very short period of time.

• Periodical: Advanced Materials Research (Volumes 217-218)
• Pages: 1747-1752
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.217-218.1747
• Online since: March 2011
• Authors: Zhi Wei Wang, Dong Dong Zhang, Xiu Hong Zhang
• Keywords: Mechanical Activation (MA), Spark Plasma Sintering (SPS), Titanium Aluminide

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