Stainless steel burnishing, a galvanic process also called black oxidation, is achieved by the following procedures:
- Pre-treatment of the material with Degreasing and Pickling
- Washing with water
- Immersion of the pieces in oxidizing solutions at a temperature of 140° C
- Repeated wash cycles in hot running water
- Final treatment with heat protection oil
In the stainless steel burnishing treatment no dangerous substances – such as lead, mercury, hexavalent cadmium, polybrominated biphenyls, polybroburated diphenyl ethers – are used. The browning process is particularly suitable also for aesthetic reasons, thanks to the pure black color of the iron if required.
Thanks to the modular burnishing, the degree of gloss of the blackened layer is possible, acting on the preparation of the underlying surface.
One of the strong points of burnishing is that it does not substantially change the thickness (and therefore the dimensions) of the treated parts. In fact, the blackening layer consists mainly of oxides with a thickness of about 0.1 micron.
Another strong point of stainless steel burnishing is the resistance to corrosion that the metal parts treated with burnishing acquire, as the pores are completely clogged with the finishing oil and do not let the water infiltrate.
All these particulars can be burnish:
- Ferrous materials
- Cast Iron
- Stainless steel (with a special procedure)