以溶膠–凝膠程序製備無機複合膜於金屬材料表面之電化學和表面特性分析

The Electrochemistry and Surface Analysis of Inorganic Coatings Prepared by Sol-gel Process on the Metal Surface

為了增加金屬基材之耐腐蝕特性，本實驗以溶膠-凝膠法製備TiO2/SiO2複合無機被覆膜並以旋轉塗佈方式被覆於不銹鋼304基材表面。研究中以TGA、DSC、FT-IR、XRD等分析儀器探討溶膠-凝膠程序之反應情形和不同鍛燒溫度之樣品結晶性分析；在耐腐蝕性能之測試，以電化學之極化曲線對於不同製備條件之無機複合膜進行測試。研究結果發現當燒結溫度增加，促使聚縮合反應的進行，在IR圖譜可觀測到Si-OH減少，Si-O-Ti增加的趨勢；在XRD中可得知被覆膜經高溫燒結後，無機陶瓷粉末結晶增加，藉此結晶性結構得以保護基材；在本實驗之操作條件下，被覆膜組成Ti/Si = 1、燒結溫度630℃、燒結時間3h之條件下可製備出耐電化學腐蝕較佳之無機被覆薄膜，所量測之電流密度為0.00039 µA/cm2，而未經被覆膜保護之不銹鋼基材其電流密度為0.023 µA/cm2。由本實驗結果證實以TiO2/SiO2當作被覆膜被覆於不銹鋼304L基材確實對其耐腐蝕特性有所提昇。

In order to improve the corrosion resistance of metal substrate, the sol-gel process is used to prepare a multi-component inorganic coating of TiO2-SiO2 on the stainless steel 304L substrate by using spin coating. In the experiment, the reaction mechanism of sol-gel process and the crystallizability of samples prepared at different temperature are analyzed by TGA, DSC, FT-IR, and XRD. In the corrosion test, some parameters, such as the TiO2 concentration, sintering temperature and sintering time are discussed by polarization method. Under the operating conditions of this study, the better anti-corrosion performance of the films are prepared at Ti/Si =1, calcinations temperature = 630℃ and calcinations time = 3h. And the current density of the coated substrate is 0.00039 µA/cm2 better than that of uncoated (0.023 A/cm2). Results indicated that a stainless steel 316L plate coated with TiO2-SiO2 films characterized a better corrosion on stainless steel.