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Abstract

Refractory multi-principal Element Alloys (MPEAs) are alloys that contain high atomic percentages of multiple refractory elements. High-throughput techniques such as directed energy deposition (DED) have been utilized to study a wide range of composition for minimal resources. A Laser Engineered Net Shaping (LENS) system is utilized to study the NbTiVZr MPEA. This project studies how the order of deposition of Nb, Ti, and Zr affects the composition of the resulting deposit. The deposition was performed on a V substrate. Six bands were created to test each ordering of Nb, Ti, and Zr. With 275 W laser melting passes and 200 W laser remelt passes, the resulting deposit was shown to not be of a constant composition through scanning electron microscopy analysis (SEM) of the cross section. For most bands, cross section line scans showed three distinct melt pools with different compositions. When Nb and Zr were layered next to each other, they fully incorporated with each other into one melt pool. The general composition of the bands was much higher in Ti than the targeted equiatomic composition. Bands tended to flake off during polishing of the cross section.

Document Type

Final Report

Author's School

McKelvey School of Engineering

Author's Department

Mechanical Engineering and Materials Science

Class Name

Mechanical Engineering and Material Sciences Independent Study

Language

English (en)

Date of Submission

1-16-2025

Available for download on Friday, January 16, 2026

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