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Are there any ways to the hard chromium coating hardness of the HV1000 above?

Hello everyone,
Are there any ways to the hard chromium coating hardness of the HV1000 above?

hf zhao
plating shop employee - Changhzou, Jingsu, China
2007

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What hardness have you achieved to date, Zhou, and how did you do it?

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2007

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The ratio is Cro3:250g/L,H2SO4:3g/L,Cr3+:2-4g/L,T:60 deg ,t:2hrs, 60A/dm2, Hardness is HV850,120 micron thickness can be achieved. Where there are problems? How did you?T hank you

J.H.ZHAO
plating shop employee - Changhzou, Jingsu, China
2007

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Readers have claimed that 900-1100 is achievable, but that the proprietary etch-free baths like Atotech's HEEF-25 generate the highest hardness. Letter 11955 addresses almost exactly the same question and is a good starting point. Good luck.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2007

In my experience conventional chrome solutions (chromic acid+sulfuric acid)just did not consistently achieve hardnesses in excess of 950HV. Tests with the high efficiency solutions i.e., HEEF 25 & Ankor 1127 gave consistent hardnesses in excess of 1050HV. Both these solutions seem identical in nature.

Colin Christian
- Sydney, Australia
2007