Development of Space Debris Protection Structure

国际空间站将于20世纪90年代末发射升空，S面临着碎片和微陨石超高速撞击的风险。完善防止碎片撞击的保护系统是一个紧迫的问题。为了进行撞击研究，需要能够使碎片模型加速超过10公里/S的模拟器。慕尼黑工业大学的E.Igenbergs教授是该项目团队的一员，他是等离子体加速器的发明者。他用新的加速器成功地加速了20公里/S 100微米的玻璃珠。然而，使用他的等离子喷枪很难有效地加速300微米或更大的珠子。我们与慕尼黑工业大学合作，成功实现了500微米玻璃微珠的加速，最高可达15公里/S。直径500微米的珠子，15公里/S是世界纪录。有效的防护结构是双元件屏蔽结构。随着冲击速度的增加，保险杠的厚度和主挡板与保险杠之间的间隙也随之增大。对由高、低冲击阻抗材料组成的双层保险板进行了减轻重量和保护结构间隙的试验。以0.5 mm的玻璃微珠作为碎屑模型。对由2024铝合金-铜和2024铝-氮化铝陶瓷组成的双层保险杠进行了试验。研究发现，由前铝合金和后氮化铝陶瓷组成的保险杠对超高速碰撞具有很高的防护能力。

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.