Optimization of enhancements to aluminum-based structural energetic materials

Warhead casings are most often made of steel due to its low cost, high strength, good manufacturability, and ability to produce dense high-speed fragments. However, inert steel does not improve blast wave characteristics. In fact, it significantly reduces peak blast pressure and impulse as energy is expended in fracturing the case and accelerating the fragments. In applications where fragmentation is unnecessary or unwanted, warhead energy output can be improved by choosing a case material that reacts in the detonation environment. Aluminum is a good candidate for this application due to its low cost, widespread availability, good manufacturability, and high enthalpy of combustion. Difficulty arises in the timely ignition of the aluminum. A plain aluminum case produces mostly large fragments which do not burn on the timescale necessary for primary blast enhancement. Alloying other elements as well as incorporating changes to case geometry can enhance breakup to improve early time ignition. This research aims to optimize several parameters to maximize aluminum casing performance. Primary diagnostics consist of dynamic pressure measurements, quasi-static pressure measurements, and high speed imaging. Effect of wall material on fragment reaction is also investigated. Additionally, tensile test specimens are fabricated and tested to verify that structural properties of the aluminum are not compromised by the optimizations. Electron microscopy is used to examine case structure after the manufacturing, which was done here at the UIUC.

Name thesis:degree_name

M.S.

Level thesis:degree_level

Thesis

Discipline thesis:degree_discipline

Mechanical Engineering

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2018

Author dc:creator

• Poirier, Nicholas

Contributors dc:contributor

• Glumac, Nick

• Aluminum
• Combustion
• Structural Energetic Material, Magnesium, Tungsten, Detonation, Case, Casing, Fragmentation

Statement dc:rights

• Copyright 2018 Nicholas Poirier

Language dc:language

en

Handle dc:identifier

http://hdl.handle.net/2142/101353

OAI identifier oai:identifier

oai:www.ideals.illinois.edu:2142/101353