An Ultrasonic Atomization System for Fabricating Novel Alloyed Reactive Metal Powders and Related Materials
Abstract
Elemental Al or Mg powders are commonly used in high explosives, propellants, pyrotechnics, or structural energetics to enhance performance, yet in many cases combustion efficiencies are well below 100percent. Some are estimated to be as low as 50percent. Recent studies suggest that multi-element or alloyed powders ignite more readily and reach much higher combustion efficiencies. However, there is little academic or Department of Defense (DoD) basic research focused on exploring the many alloys that can be formed by mixing elements with high heats of combustion such as Al, Mg, Li, B, Si, Ti, and Zr. The absence of such efforts can be attributed in part to the lack of an appropriate fabrication method - one that can produce reactive metal powders in 10-gram quantities with multiple elements for research studies AND can scale effectively to large systems to produce kilogram quantities at low cost. We propose to overcome this critical shortfall by purchasing a research-scale gas atomization system called the rePowder system that can produce 10 to 100 grams of metal powder and is ideal for basic research studies. With this novel, modular tool we will be able to fabricate reactive alloyed powders for testing while being able to vary their chemistry, microstructure, diameter, and coating. More importantly, this new fabrication tool will complement existing, DoD-funded programs that include mining of existing data sets and combinatorial methods to identify the most promising 2, 3, 4, or even 5 element chemistries from among the millions of possibilities. The existing programs also include multiple novel characterization tools that we will use to observe, understand, and eventually control the mechanisms that determine the ignition and combustion properties of these alloyed metal powders. The ability to fabricate multi-element alloy powders using a scalable technique offers the largest, most important, and most unique benefit in our long-range goal of improving the performance of metallic alloys in DoD energetic applications. No other academic or even DoD lab has this capability - as far as we know. However, the rePowder system will also benefit our ongoing study of powder compacts and our ongoing and proposed studies of refractory high entropy alloys as ideal structural energetic materials. Thus, the novel system will benefit our funded and proposed DoD research by allowing us to fabricate the most attractive alloys in multiple forms - powders, powder compacts, and small cast ingots. In purchasing the rePowder system we will advance the technical state-of-the art in fabricating multi-element, reactive metal powders for basic research in the critical field of energetic materials, and we will train a pipeline of undergraduate, masters, and PhD students in the fabrication and characterization of reactive materials so they can contribute to DoD research in the future.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Mar 06, 2024
- Source ID
- FA95502310430
Entities
People
- Timothy P. Weihs
Organizations
- Air Force Office of Scientific Research
- Johns Hopkins University
- United States Air Force