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

Te-Kang Tsao

National Institute for Materials Science

Uta Klement

Chalmers, Industri- och materialvetenskap, Material och tillverkning

Demircan Canadinc

Koç Üniversitesi

Hideyuki Murakami

Waseda University

National Institute for Materials Science

Sheng Guo

Chalmers, Industri- och materialvetenskap, Material och tillverkning

Intermetallics

0966-9795 (ISSN)

Vol. 97 58-66

Ämneskategorier

Keramteknik

Metallurgi och metalliska material

Korrosionsteknik

DOI

10.1016/j.intermet.2018.04.001

Mer information

Senast uppdaterat

2018-11-19