Abstract
By using split-Hopkinson pressure bar, scanning electron microscope and transmission electron microscope, the influence of strain rate on mechanical behavior of the as-cast CoCrFeNiNb0.5 high-entropy alloy (HEA) consisting of hexagonal close-packed (HCP) pro-eutectic phase and eutectic structure (HCP laminate and face-centered cubic (FCC) laminate) was investigated. As the strain rate increases from 1×10−4 to 6×103 s−1, it is found that yield strength does not increase evidently and that fracture strain drops drastically. Quasi-static deformation mechanism of HCP laminate is the multiplication of tangled dislocation. However, the dynamic deformation mechanism of HCP laminate is shearing. Shearing may lead to the formation of the micro-crack at low compression strain of 0.1. Since the number of the micro-crack increases rapidly with the increase of dynamic compression strain, the avalanche fracture of HEA, which is caused by the covalence of micro-crack evolved from the shearing of HCP laminate, occurred, contributing to the dynamic compressive embrittlement.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callMore From: Transactions of Nonferrous Metals Society of China
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
