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Iron-Chrome Co-Deposition

I need to plate iron with an iron-chrome alloy (10-15% Cr). Does anyone have an idea if it is possible and how can I do that?

Thanks,

Mario Tagliazucchi
student - Buenos Aires, Argentina
2004

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2004

ASM Handbook volume 5, Surface Engineering, p. 270-273 (1994), covers Cr alloy plating. One Cr-Fe formula: 250 g/L CrO3, 72.2 g/L CrCl3, 62.6 g/L FeCl2, 1 mL/L H2SO4, 20 mL/L CH3OH. The methanol reduces a portion of the Cr+6 to Cr+3. Use at 40 °C (105 F), current density 25 A/dm2 (250 A/ft2), with lead anodes. The reference (US Patent 4,615,773) mentions an optimum pH range 0.5-2.0 and Cr+6:Cr+3 ratio > 2:1, but not the plated composition. Subsequently, low-Cr+6 solutions have been developed which can be varied to produce deposits from 10 to 90% Fe (Plating and Surface Finishing, p. 39, Nov. 1989 and US Patent 5,413,646 -- J. Dash and J. DeHaven, -----).

Modern Electroplating, 4th Edn. (2000) likely has information on newer trivalent Cr solutions (more stable than Cr+6 in presence of Fe+2), but I cannot really say, as my copy is out on loan.

Ken Vlach [deceased]
- Goleta, California
Finishing.com honored Ken for his countless carefully researched responses. He passed away May 14, 2015.
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