【摘要】 采用无铬锡酸盐转化技术在镁锂合金表面形成了锡酸盐转化膜,利用扫描电镜、能谱、X射线衍射、极化曲线、析氢实验等对锡酸盐转化膜的结构和耐蚀性进行了研究。结果表明,锡酸盐转化膜由近似球形的均匀颗粒组成,较致密,主要成分为MgSnO3,呈晶态结构特征。锡酸盐转化膜的成膜时间对镁锂合金阳极极化电流有影响:成膜时间为45min时,阳极极化电流最小,转化膜对镁锂合金基体的保护作用最强。锡酸盐转化膜明显降低了镁锂合金的析氢量,改善了镁锂合金的耐蚀性。更多还原

【Abstract】 Chrome-free stannate conversion technique was used to form a stannate conversion coating on Mg–Li alloy,and the structure and corrosion resistance of the conversion coating were studied by scanning electron microscopy,energy-dispersive spectroscopy, X-ray diffraction, potentio-dynamic polarization curves and hydrogen evolution experiment.The results showed that the stannate conversion coating is compact and homogeneously consists of spherical particles, MgSnO3 crystals mainly, featuring a crystalline structure.The polarization curves indicated that the forming time of stannate conversion coating affects the anodic polarization current of Mg–Li alloy. The coating obtained for 45 min has the best protection for Mg–Li alloy. The results of hydrogen evolution experiment showed that stannate conversion coating remarkably reduces the volume of H2 evolved at Mg–Li alloy and improves its corrosion resistance.更多还原