Abstract
Nanocrystalline Nb3Al powders were prepared by hydrogen-plasma arc melting followed by mechanical grinding of hydrogen-disintegrated powders. They could be dehydrogenated at and above 873 K to yield a pure Nb3Al intermetallic compound with an apparent activation energy for dehydrogenation of 170 kJ/mol. Mechanical grinding of as-disintegrated powders for 180 ks produced Nb3Al containing a very small amount of hydrogen but their crystallite sizes were about 5 nm. On the other hand, mechanical alloying of elemental Nb and Al powders for 180 ks produced a homogeneous mixture of nanocrystalline Nb3Al of about 5 nm with a small amount of unreacted Nb. The apparent activation energy for forming Nb3Al is 240 kJ/mol. Annealing of MG and MA powders in a temperature range of 873 to 1073 K indicates that only a very slight grain growth occurs.
Original language | English |
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Pages (from-to) | 171-176 |
Number of pages | 6 |
Journal | Materials Science Forum |
Volume | 179-181 |
Publication status | Published - 1995 Jan 1 |
Externally published | Yes |
Event | Proceedings of the International Symposium on Metastable, Mechanically Alloyed and Nanocrystalline Materials - Grenoble, Fr Duration: 1994 Jun 27 → 1994 Jul 1 |
ASJC Scopus subject areas
- Materials Science(all)
- Condensed Matter Physics
- Mechanics of Materials
- Mechanical Engineering