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.
News published in Agência FAPESP Newsletter about the scholarship: