Microstructures and mechanical properties of HfNbTaTiZrW and HfNbTaTiZrMoW refractory high-entropy alloys

Publication date: Available online 12 June 2019Source: Journal of Alloys and CompoundsAuthor(s): Meng Wang, Zhaolong Ma, Ziqi Xu, Xingwang ChengAbstractW and Mo are added to the HfNbTaTiZr high entropy alloy to improve its high-temperature performance. Microstructures, and mechanical properties of new refractory high-entropy alloys, HfNbTaTiZrW (H-W) and HfNbTaTiZrMoW (H-MoW), were studied. W and/or Mo additions broaden the two-phases temperature range and introduced two disordered BCC phases in contrast with the single BCC phase in HfNbTaTiZr. Attributing to the dual-phases microstructure and the strong solid solution strengthening effect, H-W and H-MoW exhibit substantially improved yield strengths at 25–1200 °C compared with HfNbTaTiZr. Particularly, at 1200 °C, H-W and H-MoW show yield strengths of 345 MPa and 703 MPa, which are much higher than 92 MPa of HfNbTaTiZr. No phase change happens during compressive tests at high temperatures, indicating good phase stabilities of H-W and H-MoW alloys.

Source: Journal of Alloys and Compounds - June 16, 2019 Category: Chemistry Source Type: research