Shock compression of molybdenum to 2. 0 TPa by means of a nuclear explosion

Journal Article · Fri Jul 01 00:00:00 EDT 1977 · J. Appl. Phys.; (United States)

DOI:https://doi.org/10.1063/1.324094· OSTI ID:7213452

Ragan, III, C E; Silbert, M G; Diven, B C

The principal Hugoniot of molybdenum has been determined at a pressure of 2.0 TPa by measuring directly both the shock velocity and the particle velocity behind the shock. Neutrons from an underground nuclear explosion were used to generate a high-pressure shock in a slab of molybdenum by rapidly fission heating an adjacent slab of enriched uranium. A shock velocity of 18.2 mm/..mu..s ( +- 5%) was obtained by determining the transit time of the planar shock between two points in the molybdenum separated by 9.87 mm. A particle velocity of 10.7 mm/..mu..s ( +- 5%) was obtained by observing the Doppler shifts of six neutron resonances in the energy region from 200 to 800 eV in the moving shocked molybdenum. The pressure and density derived from this pair of measurements are 2.0 TPa (20 Mbar) and 24.8 g cm/sup -3/, respectively. This experiment represents the first direct determination of a point on the Hugoniot of any material in this pressure region, and the resulting data point is in good agreement with theoretical estimates. This measurement was a successful demonstration that the Doppler-shift technique can be used to obtain particle velocities in this pressure region. It appears that errors in both the shock velocity and the particle velocity can be reduced to approximately +- 2% in an improved measurement, resulting in a well-defined Hugoniot for molybdenum, which can be used as a standard in future impedance-matching experiments.

• Research Organization: Los Alamos Scientific Laboratory, University of California, Los Alamos, New Mexico 87545
• OSTI ID: 7213452
• Journal Information: J. Appl. Phys.; (United States), Vol. 48:7
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
MOLYBDENUM
SHOCK WAVES
COMPRESSION
DOPPLER EFFECT
ENERGY SPECTRA
EQUATIONS OF STATE
FISSION NEUTRONS
NEUTRON SPECTRA
NUCLEAR EXPLOSIONS
TIME-OF-FLIGHT METHOD
VERY HIGH PRESSURE
WAVE PROPAGATION
BARYONS
ELEMENTARY PARTICLES
ELEMENTS
EQUATIONS
EXPLOSIONS
FERMIONS
HADRONS
METALS
NEUTRONS
NUCLEONS
REFRACTORY METALS
SPECTRA
TRANSITION ELEMENTS
360103* - Metals & Alloys- Mechanical Properties