大气中镀锡板表面润湿性的变化

Variation of wettability of tinplate surface in ambient air

通过控制钝化过程的电荷密度,在镀锡板表面制备了不同厚度的钝化膜,以研究表层结构对镀锡板表面润湿性的影响。根据X射线光电子能谱和水接触角测量结果,分析了镀锡板在大气环境贮存过程中表面润湿性的变化。结果表明,随钝化膜厚度增大,镀锡板表层Cr的相对质量分数升高,令镀锡板表面极性提高,水接触角降低,即亲水性变好。镀锡板在大气中贮存时会吸附周围的有机物,使表层C含量增大而极性降低,最终使镀锡板表面润湿性由亲水状态向疏水状态转变。

Passivation films with different thicknesses were formed on the surface of tinplate by passivation at different electric charge densities to study the effect of surface layer structure on wettability of tinplate.The variation of wettability for the passivated tinplates during the storage in ambient air was analyzed by X-ray photoelectron spectroscopy and water contact angle measurement.The results showed that the relative mass fraction of Cr in the surface layer of passivated tinplate was increased with the increasing of passivation film thickness.As a result,the surface polarity of tinplate was improved and its water contact angle was decreased,indicating that the tinplate had better hydrophilicity.The content of C in the surface layer of tinplate was increased due to the adsorption of organic compounds on tinplate surface from the surrounding atmosphere during storage,resulting in the decrease of surface polarity,and then the switch from hydrophilicity to hydrophobicity.