Mechanical properties of multicomponent Cr40Co30Ni30 alloy produced by mechanical forming

• Grant number: 19/21133-5
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: November 01, 2019
• End date: December 31, 2021
• Field of knowledge: Engineering - Materials and Metallurgical Engineering - Physical Metallurgy
• Principal Investigator: Francisco Gil Coury
• Grantee: Fernanda Cunha Puosso
• Host Institution: Centro de Ciências Exatas e de Tecnologia (CCET). Universidade Federal de São Carlos (UFSCAR). São Carlos , SP, Brazil

Abstract

Multicomponent or High Entropy Alloys are a new class of metallic materials that do not have a main element. Among the hundreds of existing multicomponent alloys, those from the CrCoNi system stand out for their capacity of conciliating high strength and high ductility. These alloys are among the toughest materials ever developed. Recent studies have shown that non-equiatomic alloys of this system with a face-centered-cubic crystal structure and high Cr contents stand out even more. Through a combination of thermodynamic and solid solution strengthening calculations, the composition Cr40Co30Ni30 was identified as a promising candidate to combine high strength and ductility. A preliminary study presented here indicates that in fact this alloy appears to have excellent mechanical properties, however, it was only done on a pilot scale and confirmation by conventional tests is still required. In this study an ingot of this alloy will be produced, homogenized, cold-rolled and recrystallized to obtain plates with a refined grains structure. A brief phase stability study will be performed via thermal analysis to determine if the thermodynamic calculations were accurate. The recrystallized plates will have their mechanical properties tested in tension. The results will be analyzed to interpret whether the strain hardening rate of this material is high as expected and to determine the operating deformation mechanism. The understanding of the mechanical behavior of this alloy will contribute to elucidate the role of Cr in CrCoNi alloys, and it will be important to identify which composition is most appropriate to simultaneously increase the strength and ductility in alloys of this system.

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

BERTOLI, GUSTAVO; KOGA, GUILHERME Y.; PUOSSO, FERNANDA C.; CLARKE, AMY J.; KIMINAMI, CLAUDIO S.; COURY, FRANCISCO G.. Microstructure and Wear Behavior of High-Carbon Concentration CrCoNi Multi-principal Element Alloys. METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE, v. 52, n. 7, p. 3034-3050, JUL 2021. (19/00229-4, 19/21133-5)

PUOSSO, FERNANDA CUNHA; BERTOLI, GUSTAVO; COURY, FRANCISCO GIL. A Hall-Petch study of the high toughness Cr40Co30Ni30 multi-principal element alloy. Journal of Materials Research, v. N/A, p. 13-pg., 2022-10-04. (21/04302-8, 19/21133-5, 21/05408-4)