Nanocrystalline Al7075+1 wt % Zr Alloy Prepared Using Mechanical Milling and Spark Plasma Sintering.

0480207 - ÚFP 2018 RIV CH eng J - Journal Article
Molnárová, O. - Málek, P. - Veselý, J. - Šlapáková, M. - Minárik, P. - Lukáč, František - Chráska, Tomáš - Novák, P. - Průša, F.
Nanocrystalline Al7075+1 wt % Zr Alloy Prepared Using Mechanical Milling and Spark Plasma Sintering.
Materials. Roč. 10, č. 9 (2017), č. článku 1105. E-ISSN 1996-1944
R&D Projects: GA ČR(CZ) GA15-15609S
Institutional support: RVO:61389021
Keywords : gas atomization * mechanical milling * spark plasma sintering * microstructure * microhardness * recrystallization
OECD category: Materials engineering
Impact factor: 2.467, year: 2017
http://www.readcube.com/articles/10.3390/ma10091105

The microstructure, phase composition, and microhardness of both gas-atomized and mechanically milled powders of the Al7075 + 1 wt % Zr alloy were investigated. The gas-atomized powder exhibited a cellular microstructure with layers of intermetallic phases along the cell boundaries. Mechanical milling resulted in a grain size reduction to the nanocrystalline range along with an increase of the powder microhardness. Compacts prepared by spark plasma sintering (SPS) exhibited negligible porosity. The grain size of the originally gas-atomized material was retained, but the continuous layers of intermetallic phases were replaced by individual particles. Recrystallization led to a grain size increase in the SPS compact prepared from the originally milled powder. Small precipitates of the Al3Zr phase in the SPS compacts are responsible for the retainment of the sub-microcrystalline microstructure during SPS.
Permanent Link: http://hdl.handle.net/11104/0276078