Study of destruction of thin film structure by hyper-velocity impact

未来的大型空间结构，如太阳能卫星，将使用薄膜结构。对于在轨的大型结构，空间碎片和流星体以超过几公里/秒的速度进行超高速撞击是不可避免的。本研究旨在研究超高速对薄膜结构的影响。空间和宇航科学研究所的轨道炮系统已经用于撞击实验。轨道炮可以将1克聚碳酸酯弹丸的速度提高到4~5公里/秒。在实验中，对薄膜的冲击破坏、弹射以及弹丸的破坏进行了研究。研究发现，弹射器在前向膨胀了70度，对第二层靶板造成了严重破坏。破坏第二层薄膜的喷射器的总能量与喷射出的薄膜的质量成正比，与弹丸速度的平方成正比。在Impact PRO…上产生的等离子体在相同的弹丸速度下，前向有更多的页数，但在后向有较低的速度，即双极扩散速度。弹丸的破坏与薄膜靶面密度有关。对于速度为4~5 km/S的聚碳酸酯弹丸，表面密度的阈值约为0.1g/cm~2。假设在声波在弹丸中传播的时间内对弹丸施加冲击力，则该阈值对应于弹丸的压缩强度。研究了使冲击破坏最小化的薄膜结构。结果表明，格状划痕结构对抑制冲击破坏的扩展是十分有效的。对于格构型加筋结构，破坏较为严重，但仅局限于加筋结构周围的节段。这些结果为在空间建造大型薄膜结构提供了重要的工程依据。较少

A large space structure in the future, such as the solar power satellite, will use a thin-film structure. For the large structure in orbit, hyper-velocity impact of the space debris and meteoroid at a velocity more than several km/sec cannot be avoided. This research is aimed to study the hyper-velocity impact on a thin film structure. A rail gun system at the Institute of Space and Astronautical Science has been used for the impact experiment. The rail gun can accelerate a projectile of 1gram made of polycarbonate up to 4〜5 km/sec. In the experiment, the impact destruction and ejectors of the thin film have been studied as well as the destruction of the projectile. It is found that the ejectors expanded in 70 degrees in the forward and lead a serious destruction in the second film, target. The total energy of the ejectors that destroy the second film is in proportion to the mass of ejected thin film and square of the projectile velocity. The plasma which is generated at the impact pro … More pagates at the same velocity of the projectile in the forward, but at a lower velocity, the bipolar diffusion velocity, in the backward. The destroy of the projectile depends on the surface density of the thin film target. For the polycarbonate projectile at 4〜5 km/s, the threshold of the surface density is around 0.1g/cm^2. This threshold corresponds to the compression strength of the projectile if the impact force is assumed to be applied to the projectile during the time for the acoustic wave to propagate in the projectile. The thin film structure to minimize the impact destruction is also studied. It is proved that the scratched structure in the lattice-shape is quite effective to suppress the propagation of the impact destruction. For the reinforced structure in the lattice-shape, the destruction is more serious but is localized in the segment surrounded by the reinforced structure. These results give an important engineering basis for the construction of a large thin film structure in space. Less