硅烷水解时间对Q235钢表面VTES膜层耐蚀性的影响

利用硅烷溶液水解的方法,在Q235钢表面制备了乙烯基三乙氧基硅烷(VTES)膜,利用电化学阻抗谱(EIS)和动电位极化法研究了用不同水解时间的硅烷溶液制备的乙烯基三乙氧基硅烷膜在3.5%NaCl水溶液中的耐蚀性能.结果表明,用水解8天的硅烷溶液在Q235钢表面制备的乙烯基三乙氧基硅烷膜层,腐蚀过程中阳极和阴极反应受到抑制,耐蚀性能最佳;与原始Q235钢比较,腐蚀电流密度减小近3个数量级,极化电阻Rp提高近2个数量级,低频阻抗值提高至少3个数量级.

Effect of Hydrolysis Time of Silane on Corrosion Resistance of Vinyltriethoxysilane Films on Q235 Steel Surfaces

The vinyltriethoxysilane films on the surfaces of Q235 steel were prepared by hydrolysis of silane solution.The corrosion resistance of hydrolyzing vinyltriethoxysilane films prepared for different immersion time in the aqueous solution of 3.5%NaCl was investigated by the electrochemical impedance spectroscopy(EIS) and the potentiodynamic polarization.The results showed that the vinyltriethoxysilane films prepared with the silane solution hydrolyzed for 8 days on the surfaces of Q235 steel has the optimal corrosion resistance because the anode and cathode reactions are restrained during the corrosion.The corrosion current density of the Q235 steel coated with the vinyltriethoxysilane films is decreased by almost three orders of magnitude and the polarization resistance Rp is increased by about two orders of magnitude as well as its low-frequency impedance is increased by more than three orders of magnitude compared with those of the blank Q235 steel sheets without hydrolyzing vinyltriethoxysilane film.