Accelerated Discovery of Structural Materials for Harsh Environments

Multi-principal-element alloys (MPEA) have emerged as a promising group of advanced materials with unprecedented combinations of mechanical properties compared to conventional alloys. Materials that can tolerate harsh environments and retain high strength at elevated temperatures are needed to enable greater efficiency in applications including nuclear reactors, hydrogen combustion turbines, bearings, and hypersonic vehicles. We will present results from materials design efforts focused on refractory alloys that rely on high-throughput synthesis and characterization methods like additive manufacturing, tribology-based mechanical testing, and electronic-structure modeling. Discussion topics will include rapid screening of thermomechanical properties using surface (scratch)-based techniques to assess hardness, fracture toughness, and tensile ductility. We will also present preliminary results from composition tailoring of MPEA to understand and control the impacts of hydrogen exposure on selected refractory MPEAs and to develop alloy design criteria for mitigating hydrogen embrittlement.