Classic black oxidation products, as used for steel or iron materials, cannot be used to colour stainless steel materials. Below products are suitable:
Non-magnetic stainless steels BLASTAR NM Magnetic stainless steels BLASTAR M
A special working process, similar to classic steel black oxidation, must be used. Applicable technical and safety engineering requirements must also be complied with. Before stainless steel materials are coloured, they must be free of grease and clean. With some surfaces, we recommend they are first activated by suitable acidic pickling agents. Special pickling agents based on hydrochloric acid are the choice here.
The type of material and the prior mechanical processing can have a great influence on the colour result. We think it best to select the products to be used on the basis of the known data and to carry out a sample treatment before processing large surface volumes where possible. BLASTAR NM is a powder-based special black oxidation salt using as immersion process. It is suitable for uniform blackening of high alloy and stainless steels, preferably for non-magnetic stainless steels.
BLASTAR NM generates uniform, deep black surfaces. Compound parts that also include steel components can also be black oxidised. The layer is resistant to bending and wear. Conductivity and magnetic properties are not affected
BLASTAR M is a highly alkaline process providing to forms an oxidic-sulphidic coating on magnetic stainless steels, generating uniform, deep black surfaces.