Design and Production of High Strength and Toughness High Entropy Alloys for Coating Applications in Extreme Environments

• Grant number: 18/08778-4
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• Start date: August 01, 2018
• End date: January 31, 2019
• Field of knowledge: Engineering - Materials and Metallurgical Engineering - Physical Metallurgy
• Principal Investigator: Claudio Shyinti Kiminami
• Grantee: Francisco Gil Coury
• Host Institution: Centro de Ciências Exatas e de Tecnologia (CCET). Universidade Federal de São Carlos (UFSCAR). São Carlos , SP, Brazil
• Associated research grant: 13/05987-8 - Processing and characterization of amorphous, metastable and nano-structured metallic alloys, AP.TEM

Abstract

High strength and good corrosion resistance are basic requirements for materials used in extreme environments such as those found in the petrochemical, aerospace and naval sectors. High Entropy Alloys (HEAs) have a very large compositional flexibility which gives these alloys a wide range of properties. An example is the alloy Cr33.3Co33.3Ni33.3 which is one of the toughest materials ever discovered by mankind and which has excellent corrosion resistance. Despite the recent work with HEAs, several of the most promising alloys were discovered by trial-and-error, in few cases alloys were designed by predictive modeling compositions with better properties and subsequent experimental confirmation. The goal of this research project is to design different HEAs with combinations of high yield strength and high toughness in the AlCrCoNi system, a system with naturally high corrosion resistance. The compositions will be chosen using a computer alloy design system that combines: (1) Thermodynamic predictions using CALPHAD, (2) high-throughput yield strength calculations in single phase HEAs and (3) prediction of compositions with high toughnesses. Selected alloys will be produced experimentally and characterized by mechanical tests to validate the yield strength predictions. Microstructural characterizations will be performed to validate the thermodynamic predictions and to evaluate the operating deformation mechanisms. At the end of the project, it is expected to identify new high strength and toughness HEAs that can potentially be used in coatings for application in extreme environments.

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)

COURY, FRANCISCO GIL; SANTANA, DIEGO; GUO, YAOFENG; COPLEY, JOHN; OTANI, LUCAS; FONSECA, SOLANGE; ZEPON, GUILHERME; KIMINAMI, CLAUDIO; KAUFMAN, MICHAEL; CLARK, AMY. Design and in-situ characterization of a strong and ductile co-rich multicomponent alloy with transformation induced plasticity. SCRIPTA MATERIALIA, v. 173, p. 70-74, DEC 2019. (18/08778-4)

COURY, FRANCISCO GIL; WILSON, PAUL; CLARKE, KESTER D.; KAUFMAN, MICHAEL J.; CLARKE, AMY J.. High-throughput solid solution strengthening characterization in high entropy alloys. ACTA MATERIALIA, v. 167, p. 1-11, APR 1 2019. (18/08778-4)

COURY, FRANCISCO GIL; KAUFMAN, MICHAEL; CLARKE, AMY J.. Solid-solution strengthening in refractory high entropy alloys. ACTA MATERIALIA, v. 175, p. 66-81, AUG 15 2019. (18/08778-4)