Abstract:
Metal strength research under extreme conditions is of vital importancefor weapons physics and aeromechanics applications. Material’s response has an affinity with microstructure, stress history, pressure and temperature, etc. Magnetically driven isentropic compression as a new experimental technique between quasi-static and impact, has low increased entropy and temperature. Magnetic pressure produced from the current flow in the load electrode compress the sample, which is decided by the load current shape and load configuration. This experimental workwascarried out on a 10 MA facility in CAEP. The 10 MA facility includes 24 modules, which help to control the load current shape in a relative wide range, thereby provides a different ideal isentropic compression experimental platform for millimeter thick and centimeter diameter samplesto be driven with different strain rates. In this paper, based on the characteristics of 10 MA device, the sample loading path was controlled by adjusting the load current waveform. In a certain pressure-strain rate range, the strength of tantalum was experimented. The loading and unloading wave profile velocity history of tantalum samples with different thicknesses was successfully obtained, and the strength data of tantalum under a series of peak pressures were obtained. Compareing the strength results of the multiple material loading platform under different loading paths, the results in this work significantly higher than the strength under shock loading, but lower than the strength under quasi static loading based on the multi-branch confluence strength test technology, more abundant experimental studies on material dynamic characteristics will be carried out in the future.