Investigation of plastic strain accommodation and recrystallization behavior in CoCrNiCux medium-entropy alloy

• Published in: Materials letters Vol. 253; pp. 327 - 330
• Main Authors: Jodi, Dennis Edgard, Lee, Yongsu, Jang, Myeong Hyeon, Jung, Juhee, Jang, Jonggwan, Kim, Dong Woon, Kim, Jeoung Han, Jeon, Jong Bae, Park, Nokeun
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 15.10.2019; Elsevier BV
• Subjects: Accommodation; Alloys; Copper; Enthalpy; Entropy; Face centered cubic lattice; Grain boundary wetting; Interfaces; Materials science; Medium entropy alloys; Metals and alloys; Microstructure; Phase separation; Plastic deformation; Recrystallization; Solid solutions; Strain analysis; Interfaces; Metals and alloys; Medium-entropy alloys; Microstructure; Grain boundary wetting; Recrystallization
• ISSN: 0167-577X; 1873-4979
• DOI: 10.1016/j.matlet.2019.06.084

•The plastic strain and recrystallization behavior in CoCrNiCux were studied.•A phase separation of Cu-lean and Cu-rich FCC phases was observed.•Recrystallization behavior was different between the Cu-lean and Cu-rich regions.•Grain boundary wetting occurred at the Cu-lean and Cu-rich coherent interface.•The plastic strain accommodation difference was caused by the hardness difference. The plastic strain accommodation and recrystallization behavior of the medium-entropy alloy (MEA) CoCrNiCux (x = 0, 0.66, 1 in molar ratio) were investigated. The addition of Cu induced phase separation phenomenon due to the positive mixing enthalpy of Cu with other constituent elements. This resulted in an alteration of the microstructure from a single solid-solution face-centered cubic (FCC) structure to Cu-lean FCC1 and Cu-rich FCC2 phases. Here, a higher recrystallization concentration in the Cu-rich region was observed compared to that of Cu-lean region. This occurred due to the lower hardness of Cu-rich region than Cu-lean region, which caused a greater plastic strain was accommodated in the Cu-rich region than in the Cu-lean region. Consequently, Cu-rich region tended to be more extensively recrystallized compared to that of Cu-lean region.