Stainless steel can be electroplated, but it requires special pre-treatment. The passive oxide layer on stainless steel makes it difficult for metallic coatings to adhere. The most effective method for successful plating is using Nickel-Strike as an activation layer.
Step-by-Step Guide
1. Surface Cleaning
- Remove grease, oil, or contaminants with a suitable cleaner.
- Rinse thoroughly with deionized water.
2. Nickel-Strike as an Adhesion Promoter
- A thin nickel layer is deposited electrolytically.
- This creates an active surface and prevents the coating from peeling off.
- After Nickel-Strike, the workpiece should be transferred immediately to the next electroplating bath without rinsing.
3. Applying the Main Coating
After Nickel-Strike, the desired metal layer can be deposited:
- Nickel for decorative or corrosion-resistant coatings.
- Copper as an intermediate layer for further coatings.
- Chrome for shiny and wear-resistant surfaces (a dense nickel layer is recommended).
- Zinc or zinc-nickel for corrosion protection.
Why is Nickel-Strike Necessary?
- Stainless steel has a passive chromium oxide layer that prevents direct metal deposition.
- Nickel-Strike removes this layer and ensures an adhesive-friendly surface.
- Without Nickel-Strike, the electroplated coating often does not adhere permanently to stainless steel.