The effects of nanostructure on the strengthening of NiAl
The relationship between microhardness and grain size was investigated for nanocrystalline and coarse-grained stoichiometric intermetallic NiAl. The nanocrystalline NiAl specimens were synthesized through mechanical alloying with a high-energy Spex 8000 shaker mill and consolidated by shock compaction at a peak pressure of 4--6 GPa, to 83% dense compacts. The nanocrystalline NiAl compacts were also sintered at 1,073, 1,173 and 1,473 K for 2 h. The Vickers hardness of consolidated and sintered NiAl was determined by microhardness testing, and the grain size and microstructure were investigated with transmission electron microscopy. It was found that the hardness values increased with decreasing grain size of the NiAl alloy. The Vickers hardness values were approximately 650{+-}16, 690{+-}6, 800{+-}43 HV, respectively for NiAl with grain-sizes corresponding to approximately 27{+-}18, 11{+-}6 and 9{+-}6 nm. The possible strengthening mechanisms operating in NiAl are discussed.
- Research Organization:
- Georgia Inst. of Tech., Atlanta, GA (US)
- Sponsoring Organization:
- National Science Foundation
- OSTI ID:
- 20001637
- Report Number(s):
- CONF-981104--; ISBN 1-55899-458-0; ISSN 1067-9995
- Country of Publication:
- United States
- Language:
- English
Similar Records
Structure-property correlations in nanocrystalline Al-Zr alloy composites
Microhardness and elastic modulus of nanocrystalline Al-Zr