The origin and the effect of the fcc phase in sintered HfNbTaTiZr

0538131 - ÚFP 2021 RIV NL eng J - Journal Article
Lukáč, František - Vilémová, Monika - Klementová, Mariana - Minárik, P. - Chráska, Tomáš
The origin and the effect of the fcc phase in sintered HfNbTaTiZr.
Materials Letters. Roč. 286, March (2021), č. článku 129224. ISSN 0167-577X. E-ISSN 1873-4979
R&D Projects: GA MŠMT LM2018110; GA ČR GA17-17016S
Institutional support: RVO:61389021 ; RVO:68378271
Keywords : HfNbTaTiZr * Phase transformation * Powder technology * Refractory high-entropy alloys
OECD category: Materials engineering; Condensed matter physics (including formerly solid state physics, supercond.) (FZU-D)
Impact factor: 3.574, year: 2021
Method of publishing: Limited access
https://www.sciencedirect.com/science/article/abs/pii/S0167577X20319327?via%3Dihub

The growing interest in preparing refractory high entropy alloys via powder metallurgy reveals significant sensitivity to impurities, influencing the phase composition and microstructure and, consequently, the mechanical properties. Mechanical alloying of commercial purity powders is a cost-effective way of material preparation leading to a very fine microstructure when spark plasma sintering is used. However, the atmosphere of the milling process plays a significant role. This study shows that the phase composition of the HfNbTaTiZr alloy may be tailored by milling in ambient atmosphere, in argon or in nitrogen. Formation of a new fcc-ZrHfTi phase as a complex nitrogen and oxygen compound was elucidated and its significant hardening effect was shown. Finally, exceptional hardness was achieved by the synergic effect of nano-grained structure and high volume fraction of fcc-ZrHfTi phase.
Permanent Link: http://hdl.handle.net/11104/0315956