Nickel strike makes steels and stainless steels suitable for electroplating
Nickel strike was already used as an electrolyte in the 1890s. Today, nickel strike is indispensable in electroplating to prepare high-alloy stainless steels and steels for electroplating. The oxides present on the surface of high-alloyed metals impair the adhesion of coatings applied by bath electroplating or pen electroplating / pad electroplating. Therefore, pre-treatment with nickel strike is necessary.
How nickel strike works
Pre-treatment with nickel strike prepares the surface for subsequent coatings. Nickel strike is suitable for galvanic and electroless treatment. It etches the surface of the workpiece, dissolves the contained chromium, and creates a base layer of nickel in the course of this reaction. This micro-thin nickel layer forms a strong adhesive base for further coatings.
Ideally, an intermediate layer of copper or electroless or galvanic nickel should be applied after nickel strike treatment and before the final coating. The coating method—bath electroplating or pen electroplating / pad electroplating—is irrelevant.
Areas of application for nickel strike
The nickel strike process covers a wide range of applications. In addition to pre-treating high-alloy steels and stainless steels, it is also used for various non-ferrous metal alloys, such as those containing silicon, magnesium, manganese, lead, tungsten, or titanium.
Nickel-plated objects exposed to air over time may lose their typical coating properties. These so-called passivated nickel layers can be reactivated by a dip in nickel strike.
Nickel strike for galvanic and electroless application
Nickel strike is suitable for all electroplating processes, from bath electroplating to pen electroplating / pad electroplating, as well as for electroless treatment.
Fields of application:
Before use:
Thoroughly remove grease and oil using alcohol. Remove dirt and rust with suitable tools. Handle the object only with disposable gloves to prevent transferring skin grease onto the surface.
Galvanic process (with power supply):
Anodes for bath electroplating: Graphite, nickel, or platinum anodes.
Anodes for pen electroplating / pad electroplating: Graphite, nickel, or platinum anodes, stainless steel anodes also possible.
Parameters (voltage values are indicative):
- Current density: 8.5-25A/dm² (up to 50A/dm² with movement)
- Bath plating: U ≈ 2 / 3 / 4.6 V (at 5 / 10 / 20 cm distance)
- Brush plating: U ≈ 2.5-5V (approx. 3V recommended)
- Working temperature: 20-50°C
- pH value: 1
- Immersion time: 2-5min
- Deposition rate: approx. 0.03µm/min at 10A/dm² and 20°C
- Anodes: Nickel
Attention:
For stainless steel: Anode to positive pole - Workpiece to negative pole
For nickel: Anode to negative pole - Workpiece to positive pole
Apply nickel strike using the pen plating or immersion method for about 10 to 60 seconds. Rinse the workpiece briefly afterward. Aluminum objects should be processed immediately to prevent re-oxidation.
Electroless process (without power supply):
Place the electrolyte in a suitable container and heat the solution to 35 - 50°C. Submerge the workpiece for 0.5 - 3 minutes, then rinse briefly. Aluminum objects should be immersed at room temperature for a maximum of 0.5 - 1 minute!
Alternatively, nickel strike can be used at room temperature, but this requires a longer immersion time.
To prevent oxidation, nickel strike-treated objects should be further processed within 10 - 30 minutes. For aluminum, immediate processing is required.
Caution: Always wear gloves and safety goggles. Do not inhale vapors or aerosols. Use only in well-ventilated areas.
Labelling of the mixture:
Nickel-Strike
(Contains hydrochloric acid, nickel bis(sulfamate), nickel di(acetate), nickel dichloride, nickel sulfate)
Signal word: Danger
H290 May be corrosive to metals.
H314 Causes severe skin burns and eye damage.
H317 May cause an allergic skin reaction.
H335 May cause respiratory irritation.
P101 If medical advice is needed, have product container or label at hand.
P102 Keep out of reach of children. P260 Do not breathe dust/vapours/spray.
P280 Wear protective gloves and eye protection/face protection.
P301+P330+P331 IF SWALLOWED: Rinse mouth. Do NOT induce vomiting.
P303+P361+P353 IF ON SKIN (or hair): Take off immediately all contaminated clothing. Rinse skin with water or shower.
P305+P351+P338 IF IN EYES: Rinse cautiously with water for several minutes. Remove contact lenses, if present and easy to do. Continue rinsing.
P310 Immediately call a POISON CENTER/doctor.
P501 Dispose of contents/container to an appropriate recycling or disposal facility.
EUH071 Corrosive to the respiratory tract.
