X-Ray Tomography Characterization of Surface Remelted Precipitation-Hardened High-Entropy Alloys

• Grant number: 25/10806-0
• Support Opportunities: Scholarships abroad - Research Internship - Scientific Initiation
• Start date: October 01, 2025
• End date: January 31, 2026
• Field of knowledge: Engineering - Materials and Metallurgical Engineering - Physical Metallurgy
• Principal Investigator: Francisco Gil Coury
• Grantee: Ana Victória Alves Cardoso de Oliveira
• Supervisor: Michael Joseph Kaufman
• Host Institution: Centro de Ciências Exatas e de Tecnologia (CCET). Universidade Federal de São Carlos (UFSCAR). São Carlos , SP, Brazil
• Institution abroad: Colorado School of Mines, United States
• Associated to the scholarship: 23/06725-9 - Production and Characterization of Precipitation-Hardened Ni-Co-Fe-Cr-Al-Ti High-Entropy Alloy by High-Throughput CALPHAD, BP.IC

Abstract

The project aims to complement the characterization of a precipitation-hardened high-entropy alloy (HEA) from the Ni-Fe-Cr-Al-Ti-Nb system, previously developed with the aid of high-throughput CALPHAD methods. The alloy exhibits high mechanical strength and potential for additive manufacturing applications. To simulate such processing conditions, laser surface remelting will be performed on cast samples to promote the formation of microstructures typical of rapid solidification. However, conventional characterization techniques, such as optical and electron microscopy, are limited to two-dimensional analysis and cannot reveal internal defects. Therefore, the research internship abroad proposes the use of high-resolution X-ray computed tomography (XCT) as a three-dimensional, non-destructive analysis tool. The activities will be carried out at the Colorado School of Mines (USA), under the supervision of Prof. Dr. Michael J. Kaufman, using the Zeiss Xradia Versa 520 XCT system. The samples will be analyzed to detect and quantify microcracks, pores, and other defects formed during the remelting process. The data obtained will be correlated with previous microscopy and mechanical property results. The project also includes training in 3D image acquisition, reconstruction, and segmentation, contributing to a more comprehensive evaluation of the alloy and strengthening the scientific collaboration between the research groups involved. (AU)