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

Spradling, Austin Lake

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

Description

Title

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

Author(s)

Spradling, Austin Lake

Issue Date

2023-07-21

Director of Research (if dissertation) or Advisor (if thesis)

• Glumac, Nick G
• Elliott, Gregory S

Department of Study

Aerospace Engineering

Discipline

Aerospace Engineering

Degree Granting Institution

University of Illinois at Urbana-Champaign

Degree Name

M.S.

Degree Level

Thesis

Keyword(s)

• natural fragmentation
• metal hemisphere
• high explosive
• cased charge
• tantalum
• gallium
• indium
• experimental

Abstract

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.

Graduation Semester

2023-08

Type of Resource

Thesis

Copyright and License Information

Copyright 2023 Austin Lake Spradling

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