Survey of the hypervelocity impact technology and applications.

Abstract

SUMMARY/HIGHLIGHTS OF THE SYMPOSIUM Considerable progress has been made in the discipline of hypervelocity technology development and applications. There is considerable interest in the development of high speed launchers. Magnetic launchers (not a rail gun) have been developed that can accelerate plates to over 30 km/s. A time-dependent magnetic field is used to drive aluminum plates nominally 300 microns thick. Modified two-stage gun launchers also known as three stage light gas guns are being used to launch dust clouds to over 10 km/s; 1-mm size particles can be launched to around 19 km/s. Three stage gun launchers are also being designed to launch “spheres” to around 10 km/s. To date they have achieved around 8.7 km/s. The concept of using two two-stage light-gas gun throwing projectiles at each other is still being pursued. New two-stage light gas gun facilities are still being developed. There were a dozen papers on launchers presented at the meeting. Many of these hypervelocity launcher developments are motivated by space applications – especially to investigate space debris impact on targets. Cryogenic techniques are also being interfaced to determine the effects of cold targets to space debris impact. The targets are designed to represent solar arrays, satellites, debris shields, single and multiple Whipple space bumpers, etc. There is also interest in determining effects of asteroid impacts on the earth – with applications to space defense. There were approximately half a dozen papers on space debris shielding. Hypervelocity impact and penetration phenomenology is extremely varied. This topic area includes investigations tailored to address penetration phenomena in a variety of targets including metals, ceramics, composites, and geo-materials. The penetrators include long rods, and spheres. In particular penetrator shape effects, beyond simply long-rods vs. “chunky projectiles” is now being seriously investigated. Strength issues related to penetration continue to be studied. Strength of materials is determined directly to very high bar mega pressures. This includes ceramic and metallic targets. There were fourteen papers on penetration behavior capturing the above mentioned topics. Fracture and fragmentation of materials has become a topic of major interest as reflected in the number of papers on this general topic at HVIS 2005. A dozen papers, including a