Step 1
Electroless deposition
Nickel is deposited chemically, without external current – so the layer grows evenly, with no build-up on edges.
Nickel diffusion coating
Corrosion protection at the surface – the alloy stays the same.
An electroless nickel layer is deposited on the stainless or steel part and diffused into its surface by heat treatment. The result is an adherent, nickel-rich surface that resists chlorides, detergents and scale.
We apply it to heating-element sheaths for washing machines and water heaters every day – a lower-cost alternative to an Incoloy 825 sheath in hard water – and to stainless and steel parts from other manufacturers.
Water heating elements
How it is made
Two steps: deposit evenly, then diffuse.
The layer is built up chemically and then bonded into the surface by heat – it does not sit on the part like a plated skin.
Step 2
Diffusion heat treatment
Heat diffuses the nickel into the surface: the layer is bonded to the base metal and stays adherent in service.
Where it helps
Hard water, chlorides, detergents.
- Heating-element sheaths in washing machines and water heaters.
- Stainless parts that meet chloride-bearing or hard water.
- Steel parts that need a corrosion-resistant, nickel-rich surface.
- Same design: geometry, fittings and joints of the part stay as they are.
Limits
A surface treatment, not a bulk alloy.
- For the most aggressive media, a bulk alloy such as Incoloy 825 remains the safer choice.
- Scale still forms in hard water – a moderate surface load stays the first defence on heating elements.
- Mechanical damage that cuts through the layer exposes the base metal.
Test evidence
Tested in your medium – not reduced to one number.
Corrosion depends on medium, temperature and load, so we do not quote a single corrosion rate. The coating is verified on samples and tested under the conditions you specify.
- Coating thickness measured in our laboratory on samples.
- Coverage checked visually for a complete, uniform surface.
- Neutral salt spray to ISO 9227 on samples, where specified.
- Material verification by XRF analyser.
Results are reported per project, for the medium and conditions agreed with you. Background: nickel diffusion coating technology.
Validation laboratory
Tell us part, material and medium.
Send a drawing or sample parts with the operating conditions – we propose the coating route and the tests.