Accession Number : ADA132056

Title :   Microstructural Origins of Hot Spots in RDX Explosive and Several Reference Inert Materials.

Descriptive Note : Annual progress rept. no. 1, 30 Dec 81-30 Sep 82,

Corporate Author : MARYLAND UNIV COLLEGE PARK DEPT OF MECHANICAL ENGINEERING

Personal Author(s) : Elban,W L ; Coffey,C S ; Armstrong,R W ; Yoo,K -C ; Rosemeier,R G

PDF Url : ADA132056

Report Date : Mar 1983

Pagination or Media Count : 41

Abstract : Hardness testing is being used to locally deform RDX explosive and several selected reference inert crystals in a controlled manner in order to investigate the microstructural origins of hot spots. The plastic deformation in RDX was found to be very inhomogeneous. The strain fields around Knoop hardness impressions in a reasonably perfect laboratory-grown crystal were studied using surface reflection Berg-Barrett topography. Highly localized strain fields were observed, and a considerable anisotropy in Knoop hardness number was measured. A substantial variation in Vickers hardness numbers was obtained for several Holsten production-grade Class D RDX crystals. This is indicative of this material's inhomogeneous internal structure; perhaps most notable is the presence of numerous pores observed by microscopic examination. Spherical ball hardness experiments at various applied loads were performed on a single crystal of Mg0. Examination of the strain fields surrounding the resultant impressions by surface reflection Berg-Barrett topography revealed that, for increasing applied loads, the size of the strain fields was controlled by cracking. The strain fields around hardness indentations placed in a single crystal of NaCl were also investigated, in collaboration with other researchers, by synchrotron X-Ray topography. (Author)

Descriptors :   *RDX, *Inert materials, *Crystals, *Hot spots, *Microstructure, Hardness, Test methods, Plastic deformation, Magnesium oxides, Sodium chloride, Strain(Mechanics), X rays, Topography, Synchrotrons, Anisotropy, Cracking(Fracturing), Impact tests, Stress concentration, Loads(Forces), Explosives initiators, Single crystals

Subject Categories : Ammunition and Explosives
      Crystallography
      Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE