Stability of ordered L12 and B2 precipitates in face centered cubic based high entropy alloys - Al0.3CoFeCrNi and Al0.3CuFeCrNi2

By Bharat Gwalani, V. Soni, D. Choudhuri, M. Lee, Junyeon Hwang, S. Nam, H. Ryu, S. Hong, Rajarshi Banerjee. 2016

216 citations recorded by the source corpus.

Abstract Adding a small amount of Al to the well-known high entropy alloy (HEA), Al 0.1 CoCrFeNi, to form Al 0.3 CoCrFeNi, leads to the precipitation of highly refined ordered L1 2 precipitates, which are stable at 550 °C. However, the L1 2 precipitates (stoichiometry of (Ni,Cr) 3 (Al,Fe,Co)) are de-stabilized and replaced by coarser B 2 precipitates on annealing at 700 °C. Contrastingly, in the Co-free, Al 0.3 CuCrFeNi 2 high entropy alloy, the L1 2 precipitates are stable at both 550 °C (~ 5 nm) and 700 °C (~ 50 nm), and exhibit a stoichiometry of (Ni,Cu) 3 (Al,Fe,Cr). These results lead to interesting insights into the stability of ordered phases in HEAs as a function of composition and temperature.

Subfields: Aerospace Engineering, Mechanical Engineering

View Paper: https://www.semanticscholar.org/paper/d75c8e0b92eba86b9a038290e6fd93e743217f97