Going from Cr(VI) to Cr(III)

From bathroom fittings to the high-tech injection nozzles for diesel engines – chromium is beautiful, chromium is useful, chromium is everywhere. However, many chromium compounds are toxic. This is why with the new REACH regulation chromium use has to be authorized.

from Cr(VI) to Cr(III)

From the classic radiator grille to bathroom fittings and even high-tech injection nozzles for diesel engines – for decades, chrome finishes have served their many and diverse functions reliably well.

However, many chromium compounds are poisonous, especially chromium(VI) oxide, which is a by-product of some electroplating processes. This is why chromium(VI) oxide has been included in the EU list of registered substances under the REACH ­regulation. That means, starting in late 2017, chromium(VI) oxide may only be used with special approval.

For this reason, many electroplating companies have recently switched to using chromium(III) or eliminated chromium from their production altogether. Although chromium(III) electrolytes are much safer, they do have their weaknesses. They are more sensitive to contamination by other metals – even very small amounts of copper or zinc are enough to discolor the chrome layer.

Irrespective of the electrolytes, Fischer instruments can still accurately measure chrome coatings down to the nanometer. This also applies to analyzing galvanic baths with our X-RAY devices.