Research Progress of Refractory High Entropy Alloys: A Review

Abstract

Owing to superior comprehensive performance than conventional superalloys at high temperature, refractory high entropy alloy (RHEA) is becoming a promising candidate for the next generation high-temperature material. Herein, contemporary aspects of corresponding development of RHEAs are reviewed to discuss various factors affecting the organization structure and service performance. It mainly covers alloying system and strengthening mechanism, the preparation method, plastic deformation and the related mechanism, as well as microstructure control by heat treatment. Firstly, the alloy systems and strengthening mechanism are introduced. This is followed by different preparation methods and the comparison of strengths and shortcomings based on different RHEAs. Then, hot deformation behavior and plastic deformation under different loadings are analyzed. Based on this, the influence of heat treatment on microstructures prior to and after the deformation is further summarized. Finally, some important research areas to be carried out in future are pointed out. This review will give a deep understanding of the effects of different factors on the service performance and provide scientific guide in designing RHEAs with improved performance.

Ways to improve the properties of high-entropy alloys Cantor CoCrFeNiMn and CoCrFeNiAl

“…В работе [38] Подводя краткий итог рассмотрения публикаций по упрочнению пятикомпонентных ВЭС, можно констатировать, что количество статей по всем семействам ВЭС, упрочненных ванадием, цирконием, ниобием, ограничено [41; 42]. Из работ по классическому металловедению, посвященных изучению влияния микролегирования на свойства сталей, известна положительная роль ванадия, циркония и ниобия в упрочнении, например, перлитных сталей.…”

Design and Development of Stable Nanocrystalline High‐Entropy Alloy: Coupling Self‐Stabilization and Solute Grain Boundary Segregation Effects

“…HEAs possess remarkable properties such as high strength and hardness, good thermal stability, good ductility, excellent wear, oxidation, and corrosion resistance, as a result of their unique core effects. [ 46,50,51 ] Grain‐boundary segregation has been observed in microcrystalline HEAs. For example, Li et al.…”

“…Highentropy alloys (HEAs) are one of those complex multi-element alloys; these are concentrated solid solution alloys of at least four principal elements in equiatomic or near-equiatomic ratios typically within the range of 5-35 at%. [43][44][45][46][47][48][49] These alloys are characterized by a high configurational entropy of mixing as compared to conventional alloys. HEAs possess remarkable properties such as high strength and hardness, good thermal stability, good ductility, excellent wear, oxidation, and corrosion resistance, as a result of their unique core effects.…”

Recent research progress on the passivation and selective oxidation for the 3d-transition-metal and refractory multi-principal element alloys

“…Thus, MPEAs with a single-phase structure and uniform distribution of alloying elements will be expected, contributing to enhancing the composition uniformity and structural stability of the passive films [31][32][33] . MPEAs with refractory elements, such as Ti, Zr, Nb, Ta, Mo, V, W, and Hf, namely refractory multi-principal element alloys (RMPEAs), have mostly sample BCC crystal structures and may also contain some intermetallic phases, mainly B2 and/or laves [34][35][36][37][38][39] . Some RMPEAs can maintain stability in the phase structure with increasing alloying elements and heat treatment temperature [40][41][42][43] , which will be conducive to maintaining high corrosion resistance.…”