(DURIP) DEVELOPMENT OF COMBINATORIAL PROCESSING TECHNIQUES FOR ACCELERATED DISCOVERY OF COMPLEX CONCENTRATED ALLOYS (OR MULTI-PRINCIPAL ELEMENT ALLOYS) FOR STRUCTURAL APPLICATIONS

Abstract

High-performance structural materials for demanding aircraft structural applications, are often incredibly complex multi-scale systems, comprising multiple elements and phases, designed to provide an optimum balance of properties. Traditionally, the design of such structural alloys has been largely based on the principle of selecting a base element and then adding limited amounts of alloying elements to engineer their microstructure and properties via appropriate thermomechanical processing. Complex concentrated alloys (CCAs), also referred to as high entropy alloys (HEAs) and multi-principal element alloys (MPEAs), transform the traditional alloy design from a single principal element paradigm to one consisting of multiple equimolar or nearequimolar elements. These CCAs could either be a single phase disordered solid solution or consist of multiple phases, often mixtures of ordered and disordered phases, spanning multiple length scales. CCAs, in contrast to the earlier approaches of adding elements to a ‘parent’ matrix, enable us to create novel alloys with targeted properties by focusing on the unexplored central region of a multi-component phase diagram. However, investigating vast central regions of multicomponent phase diagrams is rather challenging and necessitates the development of high throughput combinatorial techniques for both alloy processing as well as characterization of microstructure and properties. The overall objective of this program is to acquire an automated multi-ingot arc-melting system that can rapidly process small samples of a large number of compositions in a relatively short period of time. The proposed arc-melting system will directly impact the wide-ranging efforts presently underway for the development of CCAs, including the AFOSR-funded effort led by the PI (AFOSR Grant Number FA9550-17-1-0395) as well as multiple in-house and external CCA-related projects being funded by AFRL. Additionally, while the proposed program is largely experimental in nature, the selection of the specific alloys and the composition ranges of interest will be guided by computation efforts being carried out by researchers and scientists at the AFRL-RX Metals Branch. These alloys could either be high entropy alloys (also referred to as compositionally complex alloys, with near equiatomic compositions of multiple elements) or alloys with one principal element and smaller additions of other solutes, which comprise the majority of presently used structural alloys.

Document Details

Document Type
DoD Grant Award
Publication Date
Mar 07, 2023
Source ID
FA95502210150

Entities

People

  • Rajarshi Banerjee

Organizations

  • Air Force Office of Scientific Research
  • United States Air Force
  • University of North Texas

Tags

Readers

  • Distributed Systems and Data Platform Development
  • Powder metallurgy of Titanium alloys.
  • Research Science/Academic Research