| The bright prospect of applications for ultraviolet laser in medical laser surgery, material processing etc. is presently limited by the lack of efficient delivery tools. Therefore, there is an urgent need of manufacturing fiber with excellent performances. This work focuses on the design and fabrication of the aluminum coating leaky type of hollow fiber.Silica capillary is chosen to be the suitable tube for fabrication hollow-core fiber by comparing series of material. Ultraviolet reflectivity of metallic aluminum is the highest versus other metallic material, so metallic aluminum is the optimum material for fabrication hollow-core fiber.Aluminum coating of electro-deposition has high purity, little pore and thickness and quality can be easily controlled versus other process. This work studied the preparation process of aluminum coating and the factor of the properties of the aluminum coating such as processing condition, pre-treatment, electroplating system, current density, and current efficiency and electroplating time etc.. It is shown that AlCl3+LiAlH4 organic solution system can be fabricated aluminum coating and processing parameter of having high reflectivity aluminum coating is obtained. All kinds of testing result and analysis indicated that keep the same aluminum concentration; the range of current density getting good aluminum coating can be accreted with the increased of aluminum chloride concentration. When the molar ratio of AlCb and LiAlRj is 5, the current density can be 10A/dm2. The weight of coating and current density has the direct ratio relation. AlCl3+LiAlH4 system conforms to the relation of current efficiency and current density of complex electrolysis lead to uniform distribution at cathode plate. Current density and electroplating velocity has line relation, but the increscent multiple of electroplating velocity issmaller than that of current density. Which indicate that current efficiency decreases with the increase of current density at AlCb+LiAlH4 system. Atl-5A/dm aluminum coating is dense and uniform, especially at 2.5A/dm . The reflectivity of aluminum coating from Aids and LJA1H4 organic solution system can be higher than 80% at ultraviolet area. With the increase of thickness of coating the reflectivity has the trend of descending. The result of reflectivity to different store time coating is shown that the oxidation of aluminum has little effect to the ultraviolet reflectivity. It is crucible to control the thickness and current density for good coating. To the AlCl3+LiAlH4 system the reflectivity is the highest when current density at 2.5A/dm2 and electroplating time at two hours. Aluminum coating has good corrosion resistance.
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