The study of electrophoretic deposition and the electrochemical properties of EPD layer

• Main Authors: Her-Yi Tang, 湯和益
• Other Authors: Shi-Chern Yen
• Format: Others
• Language: zh-TW
• Published: 2014
• Online Access: http://ndltd.ncl.edu.tw/handle/12609658431222325330

碩士 === 國立臺灣大學 === 化學工程學研究所 === 102 === In this study the phosphating and the electrophoretic deposition (EPD) of polymers on 304 stainess steel sheet and galvanized steel plates have been investigated. The effect of titanium phosphate pretreatment on the phosphating electrochemically to the 304 stainless steel sheets and galvanized steel plates has also been studied. Frthermore, by potentialdynamic polarization, open circuit potential measurements and electrochemical impedance measuremets, the electrochemical characteristics of the phosphating and EPD layers can be understood and classified with 1.85 of phosphating layer prepared by the 1% titanium compound formulation and zinc phosphating at 5 mA/cm2 and 27oC for 10 minutes, the thickness of EPD layer at applied voltage of 50 V for 3 minutes in a rectangular cell of 5 cm electrode spacing is 21um . The thickness versus electrophoretic deposition time has also been found and a simple kinetics was proposed. In the electrochemical properties test to EPD layer, the results show that electrochemical properties to EPD layer (at constant voltage of 50 V for 3 mins and at baking temperature 80oC for 30 mins) with corrosion potential, -0.98 V and coating resistance, 1380 Ohm-cm2 as increasing the baking temperature, improves the protection properties of the electrophoretic coating. Finally, the OCP and EIS of EPD layers in 3.5 % NaCl solution were measured, and it has been found that the EPD films with 50 V/5 cm has better electrochemical characteristic.