Thermophysical evaluation of a novel aluminum alloy with application to an integrated launch package

The thermophysical properties of a novel aluminum alloy are investigated. This alloy, GIGAS 30, is appealing for its increased mechanical properties compared to aluminum alloys commonly used for armatures (e.g., Al 6061, 7075). A pulsed current is used to generate the source of thermal loading. A thermocouple is used to measure the temperature rise of the material. The structure to contain the material during the discharge is configured so that very little force loading is generated during the discharge. Hence, the material failure can be essentially characterized from thermal loads alone. Finally, the thermophysical properties measured are used to assess the relative and absolute benefits and burdens when the material is selected for use in designing an integrated launch package for a railgun application. It is found that the marginal increase in breech energy and parasitic mass from the increased resistivity and density is compensated by the increased structural benefits, resulting in slightly increased system efficiency. Moreover, significant insight into material selection can be gained by using the integrated design methodology rather than selection based on one particular material property.