Electroplating of stainless steel

A novel procedure for the electrochemical deposition of a Fe-Ni-Cr alloy was investigated on stainless steel and copper substrates. The alloy contains approximately 56-58% Fe, 26-28% Ni, and 14-16% Cr in weight, close to that of a standard stainless steel 316. We show that it is possible to produce a thick (up to 23 mu m) and stressless deposit of the alloy. The first aim of this work was the development of a stable electrolyte containing Fe(II), Ni(II), and Cr(III) with a suitable chromium complexing agent. The influence of process parameters (temperature, current density, agitation of the electrolyte, and the nature of the cathode) upon the deposition was investigated. A particular study of the chromium complexation was performed. The composition and surface state of thick deposits prepared using either dimethylformamide (DMF) or glycine as a chromium complexant were compared and revealed that glycine used as a chromium(III) complexing agent, gives highly reproducible deposits with stable compositions and suitable mechanical properties and surface state. The mechanical and corrosion properties of the developed alloy were determined and compared with a standard 316 stainless steel reference sample. Finally, the successful deposition of the alloy inside a mold using the UV-LIGA technique shows the ability of the procedure to produce micro/nanostructures with highly desirable properties such as biocompatibility, durability, and resistance to corrosion.