Accelerated oxidation in ductile refractory high-entropy alloys
Artikel i vetenskaplig tidskrift, 2018
Refractory high-entropy alloys (RHEAs) are promising candidates for new-generation high temperature materials, but they generally suffer from room temperature brittleness and unsatisfactory high-temperature oxidation resistance. There currently lack efforts to address to these two critical issues for RHEAs at the same time. In this work, the high temperature oxidation resistance of a previously identified ductile Hf0.5Nb0.5Ta0.5Ti1.5Zr RHEA is studied. An accelerated oxidation or more specifically, pesting, in the temperature range of 600-1000 degrees C is observed for the target RHEA, where the oxidation leads the material to catastrophically disintegrate into powders. The pesting mechanism is studied here, and is attributed to the failure in forming protective oxide scales accompanied by the accelerated internal oxidation. The simultaneous removal of zirconium and hafnium can eliminate the pesting phenomenon in the alloy. It is believed that pesting can also occur to other equiatomic and non-equiatomic quinary Hf-Nb-Ta-Ti-Zr or quaternary Hf-Nb-Ti-Zr and Hf-Ta-Ti-Zr RHEAs, where all currently available ductile RHEAs are identified. Therefore, the results from this work will provide crucial perspectives to the further development of RHEAs as novel high-temperature materials, with balanced room-temperature ductility and high-temperature oxidation resistance.
Refractory high-entropy alloys
Pesting
High temperature materials
Oxidation resistance
Författare
Saad Ahmed Sheikh
Chalmers, Industri- och materialvetenskap, Material och tillverkning
Muhammad Kurnia Bijaksana
Chalmers, Industri- och materialvetenskap
Amir Motallebzadeh
Koç Üniversitesi
Samrand Shafeie
Uppsala universitet
Adrianna Lozinko
Chalmers, Industri- och materialvetenskap, Material och tillverkning
Lu Gan
Waseda University
National Institute for Materials Science (NIMS)
Te-Kang Tsao
National Institute for Materials Science (NIMS)
Uta Klement
Chalmers, Industri- och materialvetenskap, Material och tillverkning
Demircan Canadinc
Koç Üniversitesi
Hideyuki Murakami
Waseda University
National Institute for Materials Science (NIMS)
Sheng Guo
Chalmers, Industri- och materialvetenskap, Material och tillverkning
Intermetallics
0966-9795 (ISSN)
Vol. 97 58-66Ämneskategorier
Keramteknik
Metallurgi och metalliska material
Korrosionsteknik
DOI
10.1016/j.intermet.2018.04.001