Experimental determination of kinetic parameters in the Al-Ta, Al-Mo, Al-Nb, and Al-Ta-Ti systems and mobility modeling in the BCC region of the Al-Ta-Ti system

• Grant number: 25/23401-8
• Support Opportunities: Scholarships in Brazil - Doctorate
• Start date: November 01, 2025
• End date: March 31, 2028
• Field of knowledge: Engineering - Materials and Metallurgical Engineering - Physical Metallurgy
• Principal Investigator: Gilberto Carvalho Coelho
• Grantee: Vitória de Melo Silveira
• Host Institution: Escola de Engenharia de Lorena (EEL). Universidade de São Paulo (USP). Lorena , SP, Brazil
• Associated research grant: 25/14879-1 - Experimental determination of kinetic parameters in the Al-Ta, Al-Mo, Al-Nb, and Al-Ta-Ti systems and mobility modeling in the BCC region of the Al-Ta-Ti system, AP.R

Abstract

Refractory high entropy alloys with low specific mass are investigated due to their promising properties, especially regarding applications in high temperature environments. As part of the development of alloys for these applications, multicomponent systems with refractory metals combined with Al are investigated. Diffusion in these alloys, which becomes prevalent in applications at high temperatures, needs to be investigated to obtain kinetic data, which can be used for simulations of diffusional processes in multicomponent alloys. Another application that makes use of diffusional data is the process of deposition of protective coatings against oxidation, crucial for extending the useful life of materials used at high temperatures. To study multicomponent systems, it is essential to start from the binary and ternary systems that compose them. With all this in mind, the present project aims to experimentally determine the kinetic quantities of phases of the Al-Nb, Al-Mo, Al-Ta and Al-Ta-Ti systems, as well as the subsequent modeling of mobility in the BCC region of the Al-Ta-Ti system. For the experimental study of binary systems, diffusion couples will be made using the coating technique via pack cementation, at temperatures from 800 to 1000 °C. For the ternary system, conventional diffusion couples will be made and treated at 1100 and 1200 °C. The microstructural characterization of the samples will be carried out using scanning electron microscopy (SEM) and electron microanalysis (EDS/WDS). The data obtained will contribute to the construction of kinetic databases, essential for evaluating the useful life of materials in applications at high temperatures.