Preparation of Fe-Cr Alloy Film with A Compositionally Graded Structure by The Electroplating Method

We have succeeded in preparating an Fe-Cr alloy film with a compositionally graded structure on an Al substrate using the electroplating method. By controlling the current density with time during the electroplating process, the ratio of Cr changes gradually with the depth of the electroplated Fe-Cr coating, so that the Cr content grows proportionally upwards. Thus prepared Fe-Cr alloy coating has two distinct sets of properties, first, a high abrasion resistance and high hardness on its top surface, due to the higher Cr ratio, and secondly, a high adhesion strength and low hardness nearer the substrate, due to the lower Cr ratio in the Fe-Cr layer adjacent to the substrate.