Cold chemical blackening or metal blackening is a black finish for most ferrous metals that provides no dimensional change. It is used to add mild corrosion resistance, for decorative qualities or to minimise light reflection and has minimal build-up. The benefits of chemical blackening are:
- The base metal dimensions do not change
- Does not affect conductivity
- Improved corrosion resistances
- Provides a layer of lubrication
- No hydrogen embrittlement
- Decorative finish
- Reduced light glare
What can chemical blackening be applied to?
Cold chemical blackening can be applied to most ferrous metals, stainless steel, copper, copper based alloys, powdered metals, silver solder and zinc.
What is the chemical blackening process?
Cold chemical blackening is applied at room temperature, as opposed to hot chemical blackening. Firstly, the base metal is thoroughly cleaned and rinsed, then activated by removing oxide and adjusting the pH of the surface. It is then rinsed again before being submitted to five to six tanks containing alkaline cleaner, water, blackening compound and sealant. Finally, it is rinsed again and sealed with a light oil.
What is chemical blackening used for?
A chemical blackening finish will not chip, flake or peel off. Its reduced light glare, improved lubrication and adhesion makes it ideal for use in:
- The aerospace industry
- Optical applications
- Circuit boards
- Automotive parts – gears, chains and sprockets
- Architectural finishing
Dorsetware is a facility in Poole, Dorset that offers cold chemical blackening for various projects. Speak to a member of our technical team to learn more about cold chemical blackening or to enquire about our services call 01202 6677939 or fill in the form on our contact page.