Improvement in current efficiency of electroplated Fe-Ni films prepared in citric-acid-based baths

Fe-Ni films were electroplated in a citric-acid-based plating bath, focusing on the current efficiency of the plating process. We prepared the plating baths with various citric acid contents, and evaluated the magnetic properties of the films and the current efficiency. The film with Fe content of approximately 22 at. % was obtained by adjusting the iron sulfate content in the plating bath, and we found that the Fe-Ni films with low coercivity (<30 A/m) could be obtained in the baths with various citric acid contents. For the current efficiency, we found that the baths with low citric acid content are effective to obtain high efficiency. The bath with the citric acid content of 10 g/l showed high current efficiency (85%), and the high efficiency enables us to increase the plating rate. The maximum plating rate was 186 μm/h, and we obtained 1.3 times higher rate compared to that for our previous study. Therefore, we concluded that the bath with low citric acid content is a suitable plating bath to obtain t...