Enhanced hypervelocity launcher - Capabilities to 16 km/s

A systematic study is described which has led to the successful launch of thin flier plates to velocities of 16 km/s. The energy required to launch a flier plate to 16 km/s is approximately 10 to 15 times the energy required to melt and vaporize the plate. The energy must, therefore, be deposited in a well-controlled manner to prevent melt or vaporization. This is achieved by using a graded-density assembly to impact a stationary flier-plate. Upon impact, time-dependent, structured, high pressure pulses are generated and used to propel the plates to hypervelocities without melt or fracture. In previous studies, a graded-density impact of 7.3 km/s was used to launch a 0.5 mm thick plate to a velocity of over 12 km/s. If impact techniques alone were to be used to achieve flier-plate velocities approaching 16 km/s, this would require that the graded-density impact occur at similar to 10 km/s. In this paper, we describe a new technique that has been implemented to enhance the performance of the Sandia hypervelocity launcher. This technique of creating an impact-generated acceleration reservoir, has allowed the launch of 0.5 mm to 1.0 mm thick plates to record velocities up to 15.8 km/s. In these experiments, both titanium (Ti-6Al-4V) and aluminum (6061-T6) alloy were used for the flier-plate material. These are the highest metallic projectile plate velocities ever achieved for masses in the range of 0.1 g to 1 g.