Electrodeposition and corrosion

The variety of articles to which the process of repair by electrodeposition can be applied has extended rapidly within recent years. This method of repair was employed extensively during the war, and has been since developed to a considerable degree in America. The experience gained by increased practise has certainly resulted in the product of a better repaired article. But it must be remembered that there can be no homogeneity in the metal of the repaired article. It is for the engineer to decide in each particular case whether the absence of homogeneity, with the consequent difference between physical and mechanical properties, is harmful to his purposes. As regards protection by electrodeposition, it should be remembered that, in so far as iron is concerned, zinc is the only really protective covering that is commercially applicable. Cadmium will protect iron almost as well as zinc, but the cost of cadmium restricts its use. Chromium does not protect iron from corrosion, though the deposit of chromium can be useful for other purposes. World Power.