Impact Effect of Optical Silica Glass in the Environment of Space Micro-debris
|Keywords||Flyer silica glass high-velocity impact transimittance groundsimulation|
With the increasing of space activities, research workers on the ground payattention to this fact that the structure damage on spacecraft’ payload impacted byspace dust which including space debris and micrometeoroid. This article usedORDEM2000to cut out the environment of space debris. Based on computersimulation, technology of laser driven flyer, optical microscope, scanning electronmicroscopy and spectrophotometer were used to study the effect of high-velocityspace debris on optical glass which is used on the surface of spacecraft. Thephenomenon that the damage modes and optical transimittance of silica glassimpacted by high-velocity and small-sized aluminum flyer was researched.In this article, fused silica glass was used to replace optical glass on the surfaceof spacecraft, micro-level metal flyer such as Al and Cu were used to be space debris.Experiment simulated impact structure damage on fused silica glass by high-velocityflyer under different condition such as different flyer velocity, different flyer materials,different geometrical configuration of flyer, different flyer size and flyer impact angle.Then transimittance on the region of damaged glass were measured by usingspectrophotometer.The morphologies on the surface of impacted target after high-velocity flyerinteracting with silica glass demonstrated that the damage modes and region on thesurface of brittle glass were related with flyer velocity, materials kind, size,geometrical configuration and impact angle. Generally, the damage modes on theglass surface were divided to three types: absorption pollution on the glass bylow-velocity flyer, crater and crack generated from high-velocity impact. The resultby measuring the transimittance of damaged region on glass showed that thetransimittance of glass impacted by high-velocity decreased obviously.Combining structure damage on the surface of silica glass and its performancedegradation, in this article models were established to explain why the transimittanceof silica glass impacted by high-velocity flyer degenerated. Analyzed results showedthat the transimittance of glass decreased obviously with the increasing of damageregion. Once crater and crack generated on the surface of silica glass, thetransimittance of silica glass decreased quickly with the increasing of crater size. At last, all kinds of infinite target modes were established to explain therelationship of glass structure damage and optical transimittance. And acomprehensive mathematic model was put out to forecast the transimittance changeunder different damage modes.