Preparation and Properties of Phosphating and Silane Films on Cold Rolled Steel

The surface of cold rolled steel was treated by phosphating or silanization. The corrosion resistance and adhesion between organic coating and metal substrates were investigated by linear polarization, CuSO4 dropping and immersion in salt-water. The results showed that the corrosion resistance and adhesion of the film on cold rolled steel treated by silanization were obviously greater than those by phosphating. Scanning electron microscopy (SEM) observation indicated that the structure of the phosphate film was relatively loose, and the structure of methacryloxy propyl trimethoxyl silane film was dense and uniform.