Hostname: page-component-8448b6f56d-42gr6 Total loading time: 0 Render date: 2024-04-23T17:38:38.715Z Has data issue: false hasContentIssue false
  • English
  • Français

Comparison of Deformation and Shock Reactivity for Single Crystals of RDX and Ammonium Perchlorate

Published online by Cambridge University Press:  15 February 2011

H. W. Sandusky ,
B. C. Beard ,
B. C. Glancy ,
W. L. Elban  and
R. W. Armstrong
H. W. Sandusky
Affiliation:
Naval Surface Warfare Center, 10901 New Hampshire Ave., Silver Spring, MD 20903
B. C. Beard
Affiliation:
Naval Surface Warfare Center, 10901 New Hampshire Ave., Silver Spring, MD 20903
B. C. Glancy
Affiliation:
Naval Surface Warfare Center, 10901 New Hampshire Ave., Silver Spring, MD 20903
W. L. Elban
Affiliation:
Loyola College, Dept. of Electrical Engineering and Engineering Science, 4501 N. Charles Street, Baltimore, MD 21210
R. W. Armstrong
Affiliation:
Univ. of MD, Dept. of Mechanical Engineering, College Park, MD 20742
Get access

Abstract

Deformation of cyclotrimethylenetrinitramine (RDX) and ammonium perchlorate (AP) crystals at low strain rates was studied by diamond pyramid (Vickers and Knoop) microindentation hardness testing. RDX is two to three times harder than AP and has relatively limited slip system activity. While both crystals readily crack, cracking did not reduce hardness in RDX but did in AP. Strain fields surrounding the hardness impressions in RDX were extremely localized while in AP they extended well beyond the impressions. Shock experiments were conducted on large (5–9 mm), single crystals in a fluid-filled tank designed to permit high-speed photography and sample recovery. Reaction threshold was obtained by varying the shock pressure entering the crystals. Shock-entry orientation and large hardness impressions were used to alter microstructural responses. High-speed photography showed luminous crack propagation and reaction in both materials and the same slip deformation in AP as from hardness testing. Orientation affected the microstructural response and reaction threshold for AP, and hardness impressions sensitized chemical decomposition far from the impressions. Recovered AP crystals were much more plastically deformed than RDX crystals and were often still transparent in the region opposite shock entry. Recovered RDX crystals, at even the lowest shock pressure of 8.6 kbar, were uniformly white from a high density of fine cracks. RDX reaction threshold was ∼62 kbar versus 17 to 24 kbar for AP, depending on crystal orientation to the shock wave.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 296: Symposium Y – Structure and Properties of Energetic Materials , 1992 , 93
Copyright
Copyright © Materials Research Society 1993

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

1. Dick, J.J., Applied Physics Letters, 44 (9), 859 (1984).CrossRefGoogle Scholar
2. Dick, J.J., J. of Applied Physics, 53 (9), 6161 (1982).Google Scholar
3. Green, L.G. and James, E., in Fourth Symposium (International) on Detonation, (Office of Naval Research, ACR-126, 1965) pp. 86–91.Google Scholar
4. Elban, W.L., Hoffsommer, J.C., and Armstrong, R.W., J.of Materials Science, 19, 552 (1984).CrossRefGoogle Scholar
5. Sandusky, H.W., Glancy, B.C., Carlson, D.W., Elban, W.L., and Armstrong, R.W., J. of Propulsion and Power, 7 (4), 518 (1991).Google Scholar
6. Elban, W.L., Coyne, P.J. Jr., Sandusky, H.W., Glancy, B.C., Carlson, D.W., and Armstrong, R.W., Investigation of the Origin of Hot Spots in Deformed Crystals: Studies on Ammonium Perchlorate and Reference Inert Materials (NSWC MP 88–178, Naval Surface Warfare Center, Silver Spring, MD, 1988).Google Scholar
7. Elban, W.L., Sandusky, H.W., Beard, B.C., and Glancy, B.C., Investigation of the Origin of Hot Spots in Deformed Crystals: Final Report on Ammonium Perchlorate Studies (NSWCDD/TR-92/206, Naval Surface Warfare Center, Silver Spring, MD, to be printed).Google Scholar
8. Elban, W.L., Armstrong, R.W., Yoo, K.C., Rosemeier, R.G., and Yee, R.Y., J. of Materials Science, 24, 1273 (1989).Google Scholar
9. Armstrong, R.W. and Elban, W.L., Materials Science and Engineering, A111, 35 (1989).Google Scholar
10. Beard, B.C., Sharma, J., Sandusky, H.W., Glancy, B.C., and Elban, W.L., Shock Compression of Condensed Matter - 1991, edited by Schmidt, S.C., Dick, R.D., Forbes, J.W., and Tasker, D.G. (North-Holland, Amsterdam, 1992) pp. 571–574.Google Scholar
11. Beard, B.C., Sandusky, H.W., Glancy, B.C., and Elban, W. L., J. of Materials Research, to be printed.Google Scholar
12. Forbes, J.W., Tasker, D.G., Granholm, R.H., and Gustavson, P.K., Shock Compression of Condensed Matter -1989, edited by Schmidt, S.C., Johnson, J.N., and Davison, L.W. (Elsevier Science Publishers B.V., 1990) pp. 709–712.Google Scholar
13. Beard, B.C., Propellants, Explosives and Pyrotechnics, 16 (2), 81 (1991).Google Scholar