Explosive initiation of tungsten based reactive materials in air

Coverdill, Andrew R.

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https://hdl.handle.net/2142/18596 Copy

Description

Title

Explosive initiation of tungsten based reactive materials in air

Author(s)

Coverdill, Andrew R.

Issue Date

2011-01-21T22:51:09Z

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

• Glumac, Nick G.
• Krier, Herman

Department of Study

Mechanical Sci & Engineering

Discipline

Mechanical Engineering

Degree Granting Institution

University of Illinois at Urbana-Champaign

Degree Name

M.S.

Degree Level

Thesis

Keyword(s)

• Reactive Material
• Detonation
• Air Blast
• Tungsten Oxidation
• Zr-W
• W-Zr

Abstract

Two facilities were designed and constructed at the University of Illinois for the purpose of evaluating the enhanced blast effect of reactive materials (RM’s) initiated by a high explosive detonation. High speed pressure, shadowgraph imaging, pyrometry and spectroscopy diagnostics were developed and used concurrently for tests conducted in these facilities. Well known thermite, intermetallic and reactive metal compounds were detonated in the smaller of the two facilities. Increased pressure and light emission were measured from these RMs as compared to tests of inert steel and no material (“bare”). Shockwave velocity was similar for all tests with an RM; bare tests had a significantly higher initial velocity due to decreased impedance from the lack of an RM in the detonation path. When Aluminum was tested, AlO emission was observed in the spectra captured, but temperature calculations from pyrometry and spectroscopy data were inconsistent between tests and relative to values in the literature. These results allowed for refinement of diagnostic techniques for subsequent tests. A series of tests was conducted in the larger facility to investigate the effect of the addition of tungsten to RM’s. Quasistatic pressure (QSP) differences were observed between inert, Al-based, and Zr based tests, but all materials containing zirconium or hafnium performed similarly. QSP was converted to energy, and values for most W-containing materials were higher than the theoretical chemical energy of the non-W components of the RM, indicating that tungsten must be contributing energy to the reaction. For Zr40-W60, observed energy release was 173% of the potential energy of the Zr present. However, WO3 was not observed by XRD in powder residues collected. Due to limitations, uncertainty and quantitative error in the XRD analysis, tungsten could have reacted without observation in the residue. Further elemental analysis of the residue with a SEM/EDS process is recommended to resolve this discrepancy.

Graduation Semester

2010-12

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http://hdl.handle.net/2142/18596

Copyright and License Information

Copyright 2010 Andrew Robert Coverdill

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