Determination of interdiffusion coefficients in the BCC region of the Al-Nb-V system at 1200°C

• Grant number: 22/12877-3
• Support Opportunities: Scholarships abroad - Research Internship - Master's degree
• Start date: April 01, 2023
• End date: September 30, 2023
• Field of knowledge: Engineering - Materials and Metallurgical Engineering
• Principal Investigator: Gilberto Carvalho Coelho
• Grantee: Karoline Elerbrock Borowski
• Supervisor: Ji-Cheng Zhao
• Host Institution: Escola de Engenharia de Lorena (EEL). Universidade de São Paulo (USP). Lorena , SP, Brazil
• Institution abroad: University of Maryland, College Park, United States
• Associated to the scholarship: 21/11363-3 - Experimental investigation of kinetic parameters in the BCC region of the Al-Nb-V system, BP.MS

Abstract

Since the beginning of the 21st century a new concept of metal alloy development has attracted the interest of the scientific community. These are alloys with multi main elements, which are also known as high entropy alloys. Considering the need for new materials for advanced high temperature applications, the refractory metals have been used as constituents of such alloys. In this way, high refractory entropy alloys have appeared. Later, the idea was to add aluminum to refractory high entropy alloys with the objective of reducing their specific mass that is a critical factor in the aerospace industry, resulting in low density, refractory multi-element alloys. The kinectic study of ternary systems is an importante complement and helps the development os such alloys. In this context, one of the systems of interest is the ternary Al-Nb-V, more particularly the BCC phase stability region, which so far does not have any kinetic studies involving the three elements. The aim of this work is to determine the fluxes and interdiffusion coefficients of the V-rich BCC region of the Al-Nb-V system at 1200 °C, as a complemente of the main Fapesp research project in Brazil. The alloys of the terminal phases of the diffusion couples will be melted in an arc furnace, cut into coupons and fixed against each other by a mechanical system to maintain good contact at the interfaces. After heat treatements, the diffusion couples will be microstructurally characterized by scanning electron microscopy (SEM), and wavelength-dispersive spectroscopy (WDS). Diffusion parameters will be calculated according to the Whittle-Green method.