Colouring Stainless Steel

Colouring stainless steel in conjunction with electropolishing

The HENKEL Interference Technique (HIT) uses the property of stainless steel to build up transparent layers of chromium oxides from sulphuric solutions of suitable composition and temperature on the surface. The passive layer is strengthened and characteristic colours are produced by interference effects of the incident light depending on the layer thickness.

Thanks to the transparency of the interference film, the surface of the starting material is not obscured. The structure, e.g. a grinding or an embossing of the surface, is retained.

Since the mechanism of colouring is not based on the addition of dyes or pigments (which can change due to environmental influences), surfaces coloured according to the HENKEL Interference Technique are absolutely resistant to light, weathering and ageing.

Modification of the colouring procedure (HIT) due to the reclassification of Chromium (VI) by the European Union.

Due to modified framework conditions for handling Chromium (VI) we are rearanging our colouring procedure. Currently there are efforts made to change on a chromium-(VI)-free procedure. We are happy about every prospect who would like to support us on our way to a sustainably colouring of stainless steel as part of sample processing.

Further information also about the future of HIT can be read on the accompanying document.

Advantages of electropolished surfaces

The colouring process is usually proceded by electropolishing in order to create a uniform, defined surface condition, which gives specific properties to the stainless steel after processing with our methods.

  • They are easier to clean
  • They are more hygienic
  • They have improved corrosion resistance and increased fatigue limit
  • They are metallically pure, smooth, closed in the micro range and their extent minimised
  • They have reduced friction and wear
  • No burrs, spangles and scales on edges and surfaces.

The combination of electrochemical pretreatment and colouring according to the HENKEL Interference Technique VHC3000 offers an optimum surface treatment of semi-finished products and finished parts made of stainless steel.

  • The surface becomes beautiful and decorative as well as technically functional
  • The aesthetics of the metallic character come into their own
  • The surface of the stainless steel comes to life.


Ask today about the machining options for your components. We would be happy to give you a non-binding offer.