Experiments of the natural fragmentation of explosively-driven metal hemispheres at the 100-gram scale

To study the problem of natural fragmentation of hemispherical high-explosive metal casings, six exploratory experiments were performed at the 100-gram scale using gallium, indium, and tantalum shells with 1:1 and 2:1 explosive-to-shell mass ratios. For each test, soft catch devices were used to capture shell fragments in flight, and other post-test particulates were collected, sieved, and elementally analyzed. For gallium and indium shells, post-test particulate analyses indicate near complete, if not total, conversion to oxide. Preliminary tantalum results suggest that soft catch, particularly ballistic gelatin, along with particle analysis techniques X-ray fluorescence and X-ray diffraction are likely to be useful tools for quantifying its fragment size distribution in flight. Three new optical diagnostics - ratio pyrometry, flash radiography, and high-speed videography - have recently been implemented and show promising results for both qualitative understanding and quantitative measurement of the fragmentation process at early times. Additionally, a technique was developed for press forming a unique shell shape and mounting it in a way that better approximates a spherical system.

Name thesis:degree_name

M.S.

Level thesis:degree_level

Thesis

Discipline thesis:degree_discipline

Aerospace Engineering

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2023

Author dc:creator

• Spradling, Austin Lake

Contributors dc:contributor

• Glumac, Nick G
• Elliott, Gregory S

• Natural Fragmentation
• Metal Hemisphere
• High Explosive
• Cased Charge
• Tantalum
• Gallium
• Indium
• Experimental

Statement dc:rights

• Copyright 2023 Austin Lake Spradling

Language dc:language

en, eng

Handle dc:identifier

https://hdl.handle.net/2142/121410

OAI record oai:identifier

https://www.ideals.illinois.edu/oai-pmh?verb=GetRecord&metadataPrefix=etdms&identifier=oai%3Awww.ideals.illinois.edu%3A2142%2F121410