Optimization of Micron-Scale Aluminum Reactivity for Dynamic Loading
Abstract
There is a need to research new strategies for energetic material synthesis that will transform ordnance capabilities. The goal of this project is to synthesize aluminum particles that when combined into energetic composites will deliver kinetic energy (KE) target damage equivalent to dense inert metal projectiles and provide significant chemical energy (CE) damage upon impact including pressure-volume (PV) work to enhance pulverization and fragmentation. This overarching goal will be achieved through fundamental research that links aluminum reactive properties to impact and reaction behaviors. Most potential formulations include aluminum fuel particles in the reactive matrix. The problem is that the aluminum remains relatively unreacted during impact ignition scenarios. While theoretically aluminum heat of combustion is on the order of 7000 cal/g, the actual calorific output for impact ignition from aluminum is on the order of 1500 cal/g. One theory is that aluminum disperses due to impact before it can fully release energy. Our objective is to improve aluminum reactivity under dynamic impact ignition conditions through coupled theoretical modeling with synthesis and characterizations studies. Understanding strategies for balancing the metrics (i.e., such as trading density for gas generation) toward optimizing a mixtureÕs performance is key to engineering advanced weapons and the overall theme of this study. The project objectives are to: (1) synthesize aluminum particles and energetic material formulations that activate aluminum reactivity and combine the KE of high density composites, with CE associated with highly exothermic reactions and the PV work associated with simultaneous rapid hot gas evolution derived from polymers purposefully introduced to catalyze aluminum oxidation; (2) characterize newly synthesized formulations in terms of their mechanical, physical and thermal properties as well as their reactivity evaluated in terms of impact ignition sensitivity, reaction kinetics, gas production and energy generation; and, (3) develop mechanochemical models and simulation approaches to understand the influence of strength, plastic deformation and fracture behaviors on the energetic materials under dynamic loading. This investigation will fundamentally identify key reaction mechanisms, material properties and energetic formulations that are linked to transformative enhancements in reactive performance.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Jun 10, 2016
- Source ID
- N000141612079
Entities
People
- Michelle L. Pantoya
Organizations
- Office of Naval Research
- Texas Tech University System
- United States Navy