Abstract and subjects
In order to obtain an equation of state (EOS) and initiation information for a powdered explosive at the lower density ranges, it is necessary to press the material into the gas gun target assembly. Pressed pellets can be built into targets at the higher densities where they have physical integrity, but are difficult or impossible to handle at low densities. We have a need to employ the multiple magnetic gauge technique to measure the EOS and initiation data on low density, powdered explosives such as ammonium nitrate (AN). A "half cell" target assembly has been designed and built that has a magnetic gauge membrane glued to a triangular shaped cavity which can be loaded from the cell side. A pressing system has been built that uses a load cell to monitor the force exerted on a pressing stemple that fits into the triangular cavity. A force vs. density curve can be obtained for the particular powder and stemple/cell combination. Using this, the powdered explosive can be loaded to the desired density by pressing in increments to a given force. After the cell is loaded, a triangular plug is glued into the side to confine the sample. This paper describes the method of loading the cells with examples of pressing AN, and other powders into the target assemblies at different densities.