Hall-Petch and grain growth kinetics of the low stacking fault energy TRIP Cr40Co40Ni20 multi-principal element alloy

Autor(es)

Bertoli, Gustavo ^[1] ; Otani, Lucas B. ^[1] ; Clarke, Amy J. ^[2] ; Kiminami, Claudio S. ^[3] ; Coury, Francisco G. ^[3]

Afiliação do(s) autor(es)

^[1] Univ Fed Sao Carlos, Grad Program Mat Sci & Engn, Km 235 SP-310, BR-13565905 Sao Carlos, SP - Brazil

^[2] Colorado Sch Mines, George S Ansell Dept Met & Mat Engn, 1500 Illinois St, Golden, CO 80401 - USA

^[3] Univ Fed Sao Carlos, Dept Mat Engn, Km 235 SP-310, BR-13565905 Sao Carlos, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Applied Physics Letters; v. 119, n. 6 AUG 9 2021.
• Citações Web of Science: 0

Resumo

The Cr40Co40Ni20 multi-principal element alloy (MPEA) displays a single-phase face centered cubic initial structure, which partially transforms to hexagonal close packed (HCP) phase by transformation-induced plasticity (TRIP) during straining, as evidenced by nanometric HCP lamellae that provide enhanced mechanical properties. This MPEA also exhibits significant yield strength-grain size dependence, given by the high Hall-Petch coefficients (k = 667 MPa/mu m(-0.5) and sigma(0) = 299 MPa). The high activation energy for grain growth (Q(G) = 533 kJ/mol) leads to refined grain structures after conventional heat treatments. These features, combined with the large solid solution strengthening of Cr-rich Cr-Co-Ni MPEAs, grant the Cr40Co40Ni20 alloy a great combination of strength and ductility under tension. Finally, an empirical equation is proposed to describe the stacking fault energy (SFE) of Cr-Co-Ni alloys, contributing to the prediction of the acting deformation mechanisms. Such findings highlight the potential of compositional tuning to enhance multiple strength and deformation mechanisms in the Cr-Co-Ni system. (AU)

• Processo FAPESP: 19/00229-4 - Equilíbrio de fases e propriedades mecânicas da liga multicomponente de média entropia Cr40Co40Ni20
• Beneficiário: Gustavo Bertoli
• Modalidade de apoio: Bolsas no Brasil - Mestrado