Young Investigator Fixed Grant - Study of Phase Transformations under Extreme Conditions of CoCrNi-based High Entropy Alloys

• Grant number: 24/11008-7
• Support Opportunities: Scholarships in Brazil - Support Program for Fixating Young Doctors
• Start date: July 01, 2024
• End date: June 30, 2025
• Field of knowledge: Engineering - Materials and Metallurgical Engineering - Physical Metallurgy
• Agreement: CNPq
• Principal Investigator: Francisco Gil Coury
• Grantee: Angelo Fernandes Andreoli
• Host Institution: Centro de Ciências Exatas e de Tecnologia (CCET). Universidade Federal de São Carlos (UFSCAR). São Carlos , SP, Brazil
• Associated research grant: 24/01818-1 - Study of phase transformations under extreme conditions of multi-principal element alloys based on CoCrNi, AP.R

Abstract

High/medium entropy alloys (HEAs/MEAs), or multiprincipal element alloys(MPEAs), are emerging materials that are gaining remarkable interest. Several MPEAs combinehigh strength, ductility, fracture toughness, and resistance to oxidation, corrosion, and radiation.One of the most notable materials in this regard is the CoCrNi alloy. This makes MPEAs suitablefor sectors such as biomedical, energy, and aerospace. A key point for these materials is themartensitic transformation, responsible for many of their superior mechanical properties.However, a comprehensive thermodynamic description of this transformation is not wellunderstood. Our study assesses how changes in composition and temperatures, above and belowroom temperature (cryogenic), affect the phase transformation of CoCrNi-based MPEAs. Animportant aspect of this project will be using in situ synchrotron X-ray diffraction measurementsat high pressures. These results will expand the current knowledge of transformation-inducedplasticity (TRIP). The second objective of the research is to understand how chemical short-rangeordering can affect stacking fault energy and possibly influence the mode of plastic deformationat cryogenic temperatures and under high deformation rates.