Nanophase structure in Nb rich - Nb3Al alloy by mechanical alloying

Autor:	J.R. Groza, M.J. Tracy
Rok vydání:	1992
Předmět:	Diffraction Materials science Diffusion Metallurgy Alloy engineering.material Condensed Matter Physics Chemical engineering Torr engineering General Materials Science Grain boundary Steady state (chemistry) Dislocation Solid solution
Zdroj:	Nanostructured Materials. 1:369-378
ISSN:	0965-9773
DOI:	10.1016/0965-9773(92)90087-e
Popis:	Mechanical alloying (MA) of elemental powders was used to produce nanometer size crystals in the Nb-15.4 at. % Al alloy. A nanosize solid solution was reached when the steady state regime in the MA process was attained. The solid solution formation was explained by the enhanced diffusion due to dislocation and grain boundary multiplication by mechanical alloying. The study of solid state reactions using DTA and X-ray diffraction indicated that Nb3Al compound forms in the milled powders by heating up to 1145–1150 K. The activation energies for Nb3Al compound formation were 372.8 kJ/mole and 340.3 kJ/mole after milling for 4 and 8 h, respectively. Densities of 7.57−7.6 g/cm3 were achieved by plasma activated sintering of milled powders at 1470 K for 4 minutes in 0.5 torr vacuum under 30 MPa pressure. Nb3Al compound was formed during this short consolidation process.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::f8c3743b41889d55a4e5ea963a46863b https://doi.org/10.1016/0965-9773(92)90087-e Zobrazit plný text záznamu