氧化物涂层对航天器材料原子氧剥蚀的防护

采用磁控溅射方法在航天器常用材料聚酰亚胺(Kapton)表面沉积无机氧化物涂层(TiO₂和SiO₂),来提高材料的抗原子氧剥蚀性能.通过选择试验材料和参数,优化了沉积涂层的工艺,以克服容易产生裂纹的缺点.对材料进行了原子氧效应地面模拟试验,结果表明,在Kapton上沉积涂层后,质量损失下降了2个数量级.另外,有涂层的Kapton表面基本没有变化并且没有出现裂纹.其中,TiO₂由于热膨胀系数更接近Kapton,比SiO₂的防护效果更好.

Protection against atomic oxygen erosion of oxide coatings for spacecraft materials

To improve the atomic oxygen resistance, TiO₂ and SiO₂ coatings were deposited on polyimide (Kapton), a common material of spacecrafts using magnetron sputtering. The technic of depositing coating was optimized by selecting the experimental material and parameters to overcome the disadvantage of cracking. The atomic oxygen effect experiments were carried out. The results show that the mass loss of Kapton decreases by two orders of magnitude after depositing coatings. In addition, surfaces of coated Kapton change little and display low tendency of cracking. The thermal expansion coefficient of TiO₂ is closer to that of Kapton, so TiO₂ can provide better protection comparing with SiO₂.