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Space activities is an important manifestation of the country's comprehensive national strength, national defense, people's livelihood and other aspects play an important role. In recent years, the world's space activities have become increasingly frequent. Spacecraft in space run by the space environment. Among them, the space debris and micro-meteoroid impact threat of spacecraft have. Space debris is a human activity in space caused by solid residue, because it is in the range of spacecraft orbit, so it is more serious threat. Space debris larger than 10cm, you can through the ground, space observation system to track detection, allowing the spacecraft capable of circumvention. For small pieces, it can not be effectively observed on the only form of passive protection. American scientists Whipple Whipple shield is made in 1947 spacecraft protection program, and successfully applied to engineering practice, received good results. Its protection idea is spacecraft some distance in front bulkhead, placing a shield. Space debris at impact when the shield to get broken, thereby reducing the pressure on the bulkhead unit area of ??impact energy. In order to provide quality of protection of spacecraft systems, protective effect on the assessment of protective structures cause for concern. Given this demand, hypervelocity impact study has been developed. Hypervelocity impact is such an impact, namely: impact-generated shock pressure is much greater than the strength of the projectile and target plate. This article is based on this background, for the domestic aerospace materials Al-2A12, through the hypervelocity impact experiments to study the impact HYPERVELOCITY spherical thin aluminum debris cloud formation characteristics. Hypervelocity impact generated projectile fragmentation, with its inherent mechanical causes. Firstly, apply the theory of shock waves crushing projectile and target plate made a qualitative study, discussed the impact debris cloud formation conditions. Then use two light gas gun and high-speed flash X-ray imaging system, a series of ultra-high-speed positive impact experiments, obtained using the experimental X-ray photos and hit the target pieces, fragments of the debris cloud dimensional characteristics and quantity characteristics , speed characteristics and the characteristics of the front plate hole, the size of the fragments obtained, the number of functions and debris feature point cloud velocity function, and a correction of the empirical formula perforated front plate. This study, for hypervelocity impact debris cloud modeling is to provide a reference for the assessment of spacecraft shields made reference.
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