Abstract
This paper presents recent results on the production and properties of compacts of ultrafine powders of γ-TiAl, Metallic vapor was produced by magnetron sputtering of a TiAl target and inert gas-mediated condensation of nanometer sized particles. After collection, the particles were compacted in situ under ultrahigh vacuum conditions. The material was characterized by X-ray diffraction and hardness as a function of sintering time and temperature. Greater than 95% density was achieved in the compacts after sintering for 2 h at 450°C at which time the average grain size was still less than 20 nm. Hardness was measured as a function of grain size, and normal Hall-Petch behavior was observed, but only at grain sizes above approximately 30 nm, at which point a hardness of 12 GPa was measured. At finer particle sizes the hardness decreased with decreasing grain size.
Original language | English (US) |
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Pages (from-to) | 676-678 |
Number of pages | 3 |
Journal | Materials Science and Engineering A |
Volume | A153 |
Issue number | 1 -2 pt 2 |
State | Published - Jan 1 1992 |
Event | Proceedings of the 2nd International ASM Conference on High Temperature Aluminides and Intermetallics - San Diego, CA, USA Duration: Sep 16 1991 → Sep 19 1991 |
ASJC Scopus subject areas
- General Materials Science
- Condensed Matter Physics
- Mechanics of Materials
- Mechanical Engineering