Abstract
This paper documents results of a combined analytical/experimental program to study the behavior of lead hemispheres of various thicknesses subjected to explosive shock loading. Previous studies of collapse and jetting of lead structures indicated that, due to the low melting temperature of lead, significant amounts of vapor were present in the jet. However, its high density, ready availability and low cost make lead an attractive material for industrial and military applications. Hemispherical lead liners of three different thicknesses were fabricated into aluminum confined cavity charges using OCTOL high explosive to drive the liners. Analysis of flash radiographs of the formation and jetting process indicated a gradual transition from an apparent liquid-vapor jet for the smallest wall thickness to a liquid-solid jet for the largest thickness. This apparent phase transition of the lead liners through a region of decreasing vapor lead to an analysis of the phenomena with the two-dimensional HULL code, a finite-difference Eulerian code for computations of hydrodynamic and elastic-plastic phenomena. Good correlation (8%) was obtained between experimentally determined and computed jet characteristics, thus permitting inferences to be drawn regarding the effects of material properties and strain rates on the response of lead to shock loading. Additional computations were made with HULL for copper hemispherical liners (for which more extensive experimental data was available) and these were compared with results from HELP, another Eulerian code. The EPIC code was also used to predict the geometric characteristics and velocities of the jets from the lead liners. On the whole, good agreement with experiments was obtained from all codes indicating that existing two- and three-dimensional codes may be valuable tools for the study of explosive forming problems. In addition, the temperature profiles of the jets from the lead liners are in general agreement with the quality of the flash radiographs (i.e. appearance of vapor) and with experimental measurements of the jet surface temperature.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
