Evaluation tests on different Protective coatings in marine atmosphere

Various protective coatings (both metallic and non-metallic) were tried on mild steel and exposed to marine atmospheric as well as to industrial atmosphere. The paper deals with the performance of different coatings for a period of five years. In marine atmosphere at Digha, aluminised mild steel proved better than galvanised ones in the long run. Anodised aluminium samples gave good performance. None of the other coatings lasted more than three years. In the industrial atmosphere at Jamshedpur no significant effect was observed in all the surface coatings tested, except for some chalking and flaking off of the paint film. (Shri A.N. Mukherji, Scientist, Shri A.K. Dey, Junior Scientific Assistant, Shri S.Rao Addanki, Scientist, Shri M.N. Singh, Senior Laboratory Assistant, National Metallurgical Laboratory)