Mechanical Performances of High Entropy Alloys fabricated through Additive Manufacturing

Student’s name: Marcelo Rodriguez Home Institution: University of Texas Rio Grande Valley NNCI Site: KY Multiscale @ University of Louisville REU Principal Investigator: Dr. Kevin Walsh, Assoc. Dean of Research, Speed School of Engineering, University of Louisville REU Mentor: Dr.Thomas Berfield- Assoc. Prof. of Mechanical Engineering Department, University of Louisville Abstract: Refractory high entropy alloys have excellent mechanical properties, such as thermal stability, high yield strength, and creep resistance. They are seen as promising replacements for nickel-based superalloys like Inconel 625 and are essential in advanced applications. However, research into refractory high entropy alloys (RHEAs) has faced significant challenges over the years, such as difficulties in machining, brittleness at room temperature, and availability of powder feedstocks in additive manufacturing. Utilizing the Amazement RePowder system, novel powders can be created through a plasma and ultrasonic atomization approach. This method enables the alloying of custom materials and their transformation into spherical powders suitable for additive manufacturing. Using the atomization system, the sonotrode frequency is adjusted to 40 kHz producing powders approximately 40 microns in diameter, making them suitable for laser bed fusion. The collected powders will be characterized for size distribution and morphology, and their elemental composition will be analyzed using SEM-EDX microscopy. Once the alloy compositions are fabricated using additive manufactured, they undergo extensive testing to assess ductility, predicted solidus, and hardness. These additive-manufactured alloys are then compared to similar traditionally manufactured alloys to evaluate their overall performance. This summer’s research aims to develop refractory high-entropy alloy systems to enhance performance at extreme temperature environments.