Tuning phase-stability and short-range order through Al-doping in FeMnCoCrAlx (x
Indexed on: 18 Mar '18Published on: 18 Mar '18Published in: arXiv - Physics - Materials Science
Abstract
For FeMnCoCrAlx high-entropy alloys, we investigate the phase evolution with increasing Al-content (0 <= x <=20 at.%). From first-principles theory, the Al-doping transitions the alloy structurally from fcc to bcc separated by a narrow two-phase region (fcc+bcc), which is well supported by our experiments. We highlight the effect of Al-doping on the formation enthalpy and electronic structure of FeMnCoCrAlx alloys. As chemical short-range order (SRO) in multicomponent alloys indicates the nascent local order (and entropy changes), as well as expected low-temperature ordered behavior, we use thermodynamic linear-response to predict SRO and ordering instabilities and their phase transformation temperatures present in FeMnCoCrAlx. The predictions agree with our present and other reported experimental findings.
