EFFECT OF COLD SEALING AND SEALING ADDITIVES ON THE SEALING OF THE ANODIC OXIDATION FILMS OF ALUMINUM BY PULSE CURRENT

• Main Authors: Yen, Ju-Hsin, 鄢如心
• Other Authors: Hsing-Hsiang Shih
• Format: Others
• Language: zh-TW
• Published: 1996
• Online Access: http://ndltd.ncl.edu.tw/handle/25179147640974121702

碩士 === 大同工學院 === 化學工程學系 === 84 === In this study, the main purpose is to discuss the effects of sealing types by cold sealing and cold with additives on the properties of oxide film which is obtained in the anodizing process of aluminum A1100 by pulse current method. Three kinds of sealing type, such as cold sealing without additives, coldsealing with additives and hot water sealing are compared. The anodizing process is operated at constant voltage of 20V (various pulse current parameters are applied) in 10vol% sulfuric acid with bath temperature of 25℃. And the unsealed anodic oxide film with maximum microhardness of 275Hv can be obtained under the condition of 60% duty cycle, 500Hz frequency and 30min anodic durationtime. Cold sealing by nickel fluoride at room temperature is better than thatby other nickel salts. A sealed film (anodic duration time:20min) with weightgain of78.2 mg/dm2 and microhardness of 275Hv can be obtained under the sealingconditions of 20℃, pH=5, 5g/L nickel fluoride and 30min sealing time. The maximum value of gloss 27.8 can be obtained at sealing temperature of 10℃. When0.3g additives of aminopropyl triethoxysilane is added into the sealing solution of 5g/L nickel fluoride, the microhardness of 325Hv can be obtained. From the phosphoric-chromic acid dissolution test and acetic acud / sodium acetate dissolution test, result can be obtained that the better sealing quality is inthe order of cold sealing with additives>cold sealing without additives>hot water sealing.