Hydrodynamic modeling and explosive compaction of ceramics

Conference · Thu Sep 01 04:00:00 EDT 1977

OSTI ID:7087715

Hoenig, C; Holt, A; Finger, M; Kuhl, W

High-density ceramics with high-strength microstructure were achieved by explosive compaction. Well-characterized Al/sub 2/O/sub 3/, AlN, and boron powders were explosively compacted in both cylindrical and flat plate geometries. In cylindrical geometries compacted densities between 91 and 98 percent of theoretical were achieved. Microhardness measurements indicated that the strength and integrity of the microstructure were comparable to conventionally fabricated ceramics, even though all samples with densities greater than 90 percent theoretical contained macrocracks. Fractured surfaces evaluated by SEM showed evidence of boundary melting. Equation of state data for porous Al/sub 2/O/sub 3/ were used to calculate the irreversible work done on the sample as a function of pressure. This was expressed as a percentage of the total sample which could be melted. Calculations show that very little melting can be expected in samples shocked to less than 3 GPa. Significant melting and grain boundary fusion can be expected in samples shocked to pressures greater than 8 GPa. Hydrodynamic modeling of right cylinder compaction with detonation at one end was attempted by using a two-dimensional computer code. The complications of this analysis led to experiments using plane shock waves. Flat-plate compaction assemblies were designed and analyzed by 2-D hydrodynamic codes. The use of porous shock attenuators was evaluated. Experiments were performed on aluminum oxide powders in plane wave geometry. Microstructure evaluations were made as a function of location in the flat plate samples. 11 figures, 1 table.

• Research Organization: California Univ., Livermore (USA). Lawrence Livermore Lab.
• DOE Contract Number: W-7405-ENG-48
• OSTI ID: 7087715
• Report Number(s): UCRL-79345; CONF-770938-1
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360201* -- Ceramics
Cermets
& Refractories-- Preparation & Fabrication
360203 -- Ceramics
Cermets
& Refractories-- Mechanical Properties
360601 -- Other Materials-- Preparation & Manufacture
360603 -- Materials-- Properties
ALUMINIUM COMPOUNDS
ALUMINIUM NITRIDES
ALUMINIUM OXIDES
BORON
CHALCOGENIDES
COMPACTING
CONFIGURATION
CYLINDRICAL CONFIGURATION
ELEMENTS
EQUATIONS
EQUATIONS OF STATE
EXPLOSIVE FORMING
FABRICATION
FRACTURE PROPERTIES
HARDNESS
MATERIALS WORKING
MECHANICAL PROPERTIES
MICROHARDNESS
NITRIDES
NITROGEN COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
PNICTIDES
PRESSURE DEPENDENCE
RECTANGULAR CONFIGURATION
SEMIMETALS
VERY HIGH PRESSURE