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Disadvantages of trivalent chrome for hard chrome plating?

What are the disadvantages of using trivalent chromium for hard chrome plating processes?

Tameshwar Ramphal
engineering - Trinindad
2006

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The major disadvantage may be that it can't be done, Tameshwar :-)

At the most recent Sur/Fin conference, one of the major suppliers seemed to be hinting that very thin hard chrome may be possible from the latest generation of trivalent plating solutions, but to my knowledge it is not a proven commercial practice.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2006

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Toxicity of Cr+6, low current efficiency, poor metal distribution, burns in high-current-density areas, "white-wash" and lack of coverage around holes are some of the problems associated with Cr+6 plating baths. These factors led to the eventual development of a safer and more efficient system, based on trivalent chromium.

Trivalent chromium plating baths for decorative applications enjoyed a steady, although initially slow, acceptance as a substitute for hexavalent chromium plating. Their main attraction lies in the fact that they eliminate many of the shortcomings of hexavalent chromium solutions.

Color was a big problem of trivalent chromium plating. The plate was darker and not as shiny. This problem has been greatly reduced. The trivalent chrome systems developed by some suppliers produce plates that are as shiny and of as high a quality as hexavalent chrome plates. If the trivalent chrome parts are placed side by side with hexavalent chrome parts, however, there is a noticeable color difference.

The cost of chemicals for a trivalent system is currently higher than for a hexavalent set-up, although this might change as trivalent systems become more common.

David Shiu
- Singapore
2006