A Predictive Framework for Refractory Multi-Principal Element Alloy Design
Abstract
Motivation and Challenge: Propulsion systems in defense such as aircraft gas turbine enginesrequire materials that are resistant to high temperature degradation due to rapid oxidation, poormechanical strength, microstructure and phase transformations. Superalloys, especially Ni-basedones, have been the material of choice in load-bearing applications at the highest temperatures,especially in fracture-critical components but their extensive use is constrained by the operatingtemperatures and cost of production. Thus, design and development of refractory metallic alloys that possess improved reactive and structural properties for high temperature and pressure applications to enable better efficiency at lower operating costs, is crucial. Scientific and Technological Innovation: Multi-principal element alloys (MPEAs) have gained considerable attention from the scientific community over the last decade due to their remarkably adjustable mechanical properties (high hardness, high elevated-temperature strength, high fatigue resistance, good oxidation resistance and good age-softening resistance) arising from the uniquecompositions and micro/nanostructures. MPEAs composed of elements with high melting temperatures, for instance refractory metals, would be potentially suitable for applications at high temperatures and pressures, and minimize costs. The overarching goal of this proposal is to describe a plan for examining and designing refractory MPEAs that provide superior structural properties and oxidation resistance at elevated temperatures. A fundamental knowledge base onthe microstructure and phase equilibria of these advanced multi-element materials will be established that is vital for understanding the formation of solid solution and secondary phases, material thermodynamics and betterment of material properties. This goal will be accomplished through a combination of computational and experimental efforts employed synergistically for a hypothesis-driven design.Impact of the research: This multidisciplinary proposal rigorously integrates advances in materials chemistry, high performance computations, state-of-the-art synthesis, characterization and performance-driven materials optimization heuristic, all geared towards addressing a materials engineering problem, that is timely and extremely critical for future DoD applications: (1) An atomistically tailored material composition will be obtained that increases the mechanical strength especially at temperatures above 1000oC and resistance to ???pesting??? in oxygen environments for application in propulsion systems. (2) The computational framework will significantly reduce the timeline for design, synthesis and characterization of novel MPEAs for high temperature applications.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Jul 26, 2018
- Source ID
- N000141812484
Entities
People
- Ganesh Balasubramanian
Organizations
- Lehigh University
- Office of Naval Research
- United States Navy