Study on the Dual-Element Meteoroid-Shield Structure of Space Experiment Free Flyer

研制了一种新型的两级等离子体加速器，用于微弹丸的超高速加速。加速器由作为第一级的气体枪和作为第二级的等离子体加速器组成。经确认，在激光触发系统启动的任何时刻，两阶段操作均表现良好。结果表明，在两阶段的操作中，弹丸的速度增加，并且速度在很大程度上取决于加速开始时的位置。弹丸对目标的命中率也明显提高。一个直径为500 μ m的玻璃珠被加速到10公里/秒。对于亚毫米级的玻璃弹，在5052铝合金靶上发生从塑性到流体动力学状态的转变，速度约为5 km/s。研究了弹坑尺寸与弹丸速度-质量的关系。在此基础上，研究了小尺寸弹丸超高速撞击空间实验自由飞体的防护问题。

A new two-stage plasma accelerator was developed for conducting the hypervelocity acceleration of microprojectiles. The accelerator consisted of a gas gun as a first stage and a plasma accelerator as the second stage. It was confirmed that the two-stage operation performed well at any timing started by the laser trigger system. It was found that the velocity of projectiles was increased in the two-stage operation and that the velocity greatly depended on the position at the beginning of acceleration. The impact rate of projectiles on a target was also markedly increased. A glass beads with 500 mum in diameter has been accelerated up to 10 km/sec. A transition from plastic to hydrodynamic regime on 5052 aluminum alloy target occurs at about 5 km/sec for submillimeter-sized glass projectiles. Relation between crater size and projectile velocity-mass was studied. Protection form the hypervelocity impact of small size projectile to space experiment free-flyer was also investigated on the basis of the dual-element meteoroid-shield structure.