Development of Metastable High Entropy Alloys for Additive Manufacturing

Zachary Sims | 21-ERD-046

Project Overview

New materials and their application in emerging technologies has been the driving force of innovation for the whole of human history. In the last two centuries, metal alloys have made possible the development of numerous modern technologies. That trend is set to continue as high entropy alloys, also known as compositionally complex alloys (CCAs), reshape the methods most often used to develop novel alloys. This project focused on the development of a set of CCAs optimized for strength at temperatures up to 1000°C and that can be produced using additive manufacturing. The results detail the design of an alloy system using CALculation of PHAse Diagrams (CALPHAD) modeling coupled to high throughput experimentation. This process resulted in the discovery of CCA with strength and ductility above that of common super alloys while containing no cobalt, a critical material for the energy transition. Further, this report highlights the efforts to design a small-scale additive manufacturing system that could make use of LLNL owned laser capabilities for reduced volume printing, a key step in the alloy fit for purpose development pipeline.

Mission Impact

The results of this project improve the labs competencies in advanced material and manufacturing while also pushing forward the state of the art for Co-free transition metal high temperature CCAs. The developed alloy is a key material for achieving several of the desired milestones in laboratory and DOE's efforts to design new energy and structural technologies.

Furthermore, the high throughput coupled modeling/experimental platform developed opens the door to an accelerated alloy design pipeline. The capability for high throughput material design addresses the need for meeting highly specific mission critical application and design milestones on shortened timelines. 

Publications, Presentations, and Patents

Zachary Sims, Aurelien Perron, Alfred Amon, Hunter Henderson, Michael Thompson, Max, Neveau, Orlando Rios, Scott McCall,"Suitability of CoCrFeMn(Ni3Al)x High Entropy Alloys for Additive Manufacturing" (Presentation, Materials Science & Technology Conference and Exhibition, Pittsburgh, Pennsylvania, October, 2022).

Zachary Sims, Aurelien Perron, Alfred Amon, Hunter Henderson, Brandon Bocklund, "Investigation of Cobalt Free Multi-Principal Element Alloy Candidates for Reducing Material System Criticality" (Presentation, Minerals, Metals, & Materials Society Annual Meeting and Exhibition, San Diego, California, March, 2023).