Impact of vanadium (V) content on in-situ oxidation, high temperature mechanical strength and tribological properties of Al0.5CrFeNiVx high entropy alloys
In this study, four vanadium (V) containing high entropy alloys (HEAs) Al0.5CrFeNiVx (x = 0.25, 0.5, 0.75, 1.0) were developed and investigated, in terms of examining the influence of V content on their microstructure, in-situ oxidation behavior, high temperature mechanical strength, and high temperature tribological performances. An increase in the V content causes precipitation of the Laves phase (VAl2) in the body-centered cubic (BCC) matrix. This structural transition increases the alloy hardness and compressive strength through solid solution strengthening, precipitation strengthening and grain refinement strengthening. When x is increased from 0.25 to 1, the maximum compressive strength increases from about 2476 to 3241 MPa at room temperature and from about 521 to 797 MPa at 700 °C, respectively. In-situ oxidation investigation reveals that a higher V content accelerates the oxidation and provides a direct evidence of vanadium oxides melting at 700 °C and thus forming the liquid oxide phases on the surface of HEAs. During high temperature tribological contact, the liquid oxide phases minimize the friction, allowing thicker and more complex oxide layers to form on the worn surface to improve the HEAs’ wear resistance. The findings in this work contribute to the development of novel HEAs with superior properties for potential applications that need outstanding mechanical strength, wear resistance, and thermal stability.
Funding
Fabrication of large-scale 2D metallic nanosheets by accumulative rolling : Australian Research Council (ARC) | DE180100124
ARC Training Centre for Innovative Composites for the Future of Sustainable Mining Equipment : Australian Research Council (ARC) | IC220100028
History
Journal title
Tribology InternationalVolume
202Article/chapter number
ARTN 110375Total pages
20Publisher
ELSEVIER SCI LTDPublisher website/DOI
Publication status
- Published