Development of Space Debris Protection Structure

将于1990年代末发射的国际空间站面临碎片和微陨石超高速撞击的危险。完成碎片撞击防护系统是一个紧迫的问题。进行撞击研究需要能够使碎片模型加速超过10km/s的模拟器。慕尼黑工业大学的E. Igenbergs教授是这个项目团队的一员，他是等离子体加速器的发明者之一。他使用他的新加速器成功地将100个玻璃珠加速到每秒20公里。然而，使用他的等离子枪很难有效地加速300mum或更大的珠子。我们与慕尼黑工业大学合作，成功地将500mum玻璃珠加速至15km/s。价值，500毫米直径的珠子和15公里/秒的速度是世界纪录。有效的保护结构是双元件屏蔽结构。要求随着冲击速度的增大，保险杠板的厚度和主壁与保险杠之间的间隙增大。采用高、低冲击阻抗材料组成的双层保险杠板，对其减重和减小保护结构间隙进行了试验。以0.5mm玻璃微珠作为碎片模型。对2024铝合金-铜和2024铝氮化铝陶瓷双层保险杠板进行了试验研究。研究发现，前铝合金后氮化铝陶瓷组成的保险杠对超高速碰撞的防护能力很高。

The international space station, which will be launched in the late 1990's, is exposed to the risk from hypervelocity impact of debris and micrometeorites. Completion of the protection system from debris impact is an urgent problem. The simulator capable of acceleration of debris model over 10km/s is needed to conduct the impact study. Prof. E. Igenbergs of Technical University of Munich, who is one of this project team, is an inventor of the plasma accelerator. He succeeded 20km/s acceleration of 100mum glass beads using his new accelerator. However it is difficult to accelerate effectively 300mum or larger beads using his plasma gun. We conducted successfully acceleration of 500mum glass beads up to 15km/s by cooperation with Technical University of Munich. The value, 500mum diameter bead and 15km/s is the world record. The effective protection structure is the dual element shield structure. It is required to increase of thickness of the bumper plate and gap between main wall and bumper with increasing impact velocity. A double layer bumper plate consisted of high and low shock impedance materials were tested for reducing weight and gap distance of the protection structure. 0.5mm glass beads were used as a model of debris. The double layered bumper plates consisted of 2024 Al alloy-copper and 2024 Al-aluninum nitride ceramic were tested. It was founded that protection ability of the bumper consisted of front-aluminum alloy and rear-aluninum nitride ceramics is very high for the hypervelocity impact.