Microstructure and Mechanical Strength of Attritor-Milled and Spark Plasma Sintered Mg-4Y-3Nd Alloy

0531570 - ÚJF 2021 RIV CH eng J - Journal Article
Zemková, M. - Minárik, P. - Knapek, Michal - Šašek, S. - Dittrich, J. - Král, R.
Microstructure and Mechanical Strength of Attritor-Milled and Spark Plasma Sintered Mg-4Y-3Nd Alloy.
Crystals. Roč. 10, č. 7 (2020), č. článku 574. ISSN 2073-4352. E-ISSN 2073-4352
R&D Projects: GA MŠMT EF16_013/0001794
Institutional support: RVO:61389005
Keywords : magnesium * spark plasma sintering * attritor-milling * microstructure * mechanical strength
OECD category: Condensed matter physics (including formerly solid state physics, supercond.)
Impact factor: 2.589, year: 2020
Method of publishing: Open access
https://doi.org/10.3390/cryst10070574

Gas-atomized powder of an Mg-4Y-3Nd magnesium alloy was attritor-milled at room temperature in an argon atmosphere for two time periods-1.5 and 5 h. Subsequently, the gas-atomized powder as well as both of the milled powders were spark plasma sintered at four temperatures, 400, 450, 500, and 550 degrees C, for 3 min. The effect of the milling on the powder particles' morphology and the microstructure of the consolidated samples were studied by advanced microscopy techniques. The effect of the microstructural changes, resulting from the pre-milling and the sintering temperature, on the mechanical strength was investigated in compression along and perpendicular to the sintering load direction. Both the compression yield strength and ultimate compression strength were significantly affected by the grain size refinement, residual strain, secondary phase particles, and porosity. The results showed that attritor-milling imposed severe deformation to the powder particles, causing a significant grain size refinement in all of the consolidated samples. However, 1.5 h of milling was insufficient to achieve uniform refinement, and these samples also exhibited a distinctive anisotropy in the mechanical properties. Only a negligible anisotropy and superior yield strength were observed in the samples sintered from 5 h milled powder, whereas the ultimate strength was lower than that of the samples sintered from the gas-atomized powder.
Permanent Link: http://hdl.handle.net/11104/0310198