3D-PRINTED, HIERARCHICAL POLYMER-BONDED ENERGETIC COMPOSITES WITH ELECTROMAGNETICALLY SWITCHABLE POROSITY
Abstract
The objective of this project is to develop the capability to electromagnetically control porosity within polymer-bonded energetic materials (EMs) toward the goal of enabling dynamic control of EM sensitivity and performance. A new class of hierarchical, polymer-bonded composites is proposed, whose porosity and shock sensitivity can be dynamically controlled through illumination by a pulse of electromagnetic radiation. This unique capability is enabled by both exploiting the microwave transparency of many EMs and spatially tailoring the local microwave-frequency absorption of polymer-bound composites through addition of microwave ignitable nanoscale energetic additives to the matrix of a composite energetic. Spatial distribution of microwave ignitable energetics will be precisely controlled through use of a novel, multi-jet fusion 3D printing technique (P-MJF) capable of high solids fraction, high density prints. The scientific approach taken in this effort begins with fundamental studies to optimize both the multi jet fusion 3D printing process and to optimize microwave sensitive energetic additives. Meso-scale simulations using the SCIMTAR3D code, conducted on X-ray ?CT reconstructions of as-fabricated and microwave-damaged (porosity containing) microstructures to assess porosity effects on shock sensitivity. This project will enable new spatially controlled, hierarchical polymer-bonded composites with switchable porosity and shock sensitivity, potentially improving the safety of PBXs without sacrificing explosive performance. The effort will result in advancement in a number of knowledge areas of relevance to both additive manufacturing of EMs and dynamic control of EM performance.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Aug 12, 2021
- Source ID
- FA95502010070
Entities
People
- Xuan Song
Organizations
- Air Force Office of Scientific Research
- United States Air Force
- University of Iowa