Abstract
Magnesium alloyed by yttrium and neodymium was prepared by powder metallurgy. Attritor-milling of the gas-atomized powder at the room temperature was conducted for two milling times - 1.5 and 5 hours.
Subsequently, the powders were consolidated by spark plasma sintering method at the temperature range of 400-550 °C. The influence of the pre-milling and sintering temperatures on the microstructure was investigated by advanced microscopy techniques.
It was found that attritor-milling lead to produce of highly deformed powder of disc-like morphology. The milling had a minor effect on the particle size but a significant effect on their microstructure.
Consequently, the milling did significantly affect the microstructure of the sintered samples as well. The severe plastic deformation introduced during the milling caused significant grain refinement in the sintered samples.
Ultrafine-grained structure with the grain size of ~500 nm was achieved in sample sintered from 5 h milled powder at 400 °C. The increasing sintering temperature lead to the grain growth.
The formation of disc-like particles after milling cause formation of a layer-like microstructure which caused formation of strong texture.