Abstract
The CoCrNi and precipitate-hardened (CoCrNi)94Ti3Al3 medium entropy alloys (MEAs) have attracted much attention, due to their exceptional mechanical properties, whereas the hot deformation characteristics have not been revealed. In the present study, we investigated the dynamic recrystallization behavior and microstructure evolutions of the two MEAs hot-compressed at single-phase temperatures. The constitutive equation was obtained, and microstructures were observed. Discontinuous dynamic recrystallization acted as a key mechanism of grain refinement at a relatively higher temperature and lower strain rate, which leads to the formation of a homogeneous grain structure. The addition of Ti and Al promoted dynamic recrystallization due to the solid solution hardening effect. The results provide valuable guidelines for microstructure refinement via thermomechanical processing.
Highlights
High entropy alloys (HEAs) comprising more than four principles elements have attracted much academic attention, due to their unusual structures and properties [1,2]
medium entropy alloys (MEAs) were investigated by uniaxial hot-compression to a height reduction of 63% corresponding to a true strain of 1.0, which was conducted at temperature ranges from 850 to 1100 ◦ C with strain rate ranges from 0.001 to 1 s−1
The apparent activation energy for the hot deformation was evaluated as 401.08 kJ/mol (CoCrNi) and 566.128 kJ/mol ((CoCrNi)94 Ti3 Al3 ), respectively, which is higher than that of CoCrFeMnNi high entropy alloys
Summary
High entropy alloys (HEAs) comprising more than four principles elements have attracted much academic attention, due to their unusual structures and properties [1,2]. HEAs, the face-centered cubic (fcc) single-phase CoCrFeMnNi and CoCrFeNi alloys are the most widely investigated, which exhibit exceptional mechanical properties at both ambient and cryogenic temperatures [2,3,4,5]. An intermediate SFE (15–45 mJ/m2 ) promotes the formation of mechanical twinning [10], whereas a low SFE (
Sign-in/Register to view highlights & summary 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 callDisclaimer: 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.
