The Exceptional Strong Face-centered Cubic Phase and Semi-coherent Phase Boundary in a Eutectic Dual-phase High Entropy Alloy AlCoCrFeNi.

ABSTRACT: Second phase strengthening has been applied to high entropy alloys (HEAs) for optimizing mechanical properties. In this study, by conducting mechanical testing of a eutectic dual-phase AlCoCrFeNi HEA with homogenous distribution of body-centered cubic (BCC) and face-centered cubic (FCC) lamellar phases inside a transmission electron microscope, we found that although BCC was truly the hard phase, decreasing the proportion of BCC phase in fact increased the strength due to the existence of chemically disordered semi-coherent phase boundaries, which acted as potent impediments to dislocation motion resulting in dense dislocation storage in FCC phases. Moreover, the difficulty in dislocation glide caused massive cross-slip, and the interaction between primary slip arrays and cross-slip system

SUBMITTER: Wang Q 

PROVIDER: S-EPMC6175879 | biostudies-literature | 2018 Oct

REPOSITORIES: biostudies-literature