An electroless nickel coating is a dense alloy of nickel and phosphorus. The amount of phosphorus co-deposited can range from less than 2% to more than 12%, depending upon bath formulation, operating pH and bath age.
An electroless nickel coating with a high phosphorous content is extremely effective in the oil, gas and coal industry. These environments are highly corrosive and therefore require a phosphorous content of more than 10%.
Phosphorous content in electroless nickel deposits can vary from 1 – >12% by weight and the variation can be controlled to result in a number of deposit types.
High Phosphorus Deposits
- Typically contain 10-12% phosphorus
- Very high corrosion resistance
- Complete lack of magnetic response.
- Most conditions in the highly corrosive oil, gas and coal industry require deposits with a high phosphorus content (>10%).
Low Phosphorus Deposits
- Typically contain 2-5% phosphorus.
- Improved hardness and wear characteristics
- Higher temperature resistance
- Increased corrosion resistance in alkaline environments.
- Best suited to the chloro-alkali industry, such as the transportation of liquid soda.
- Enhanced solderability and bondability, especially in electronic applications.
Mid Phosphorus Deposits
- Typically contain 6-9% phosphorus
- Bright and aesthetically pleasing
- Good hardness and wear resistance
- Moderate corrosion resistance
- Plate at a relatively low temperatures (75-140°F, 24-60°C)
- Suitable for plating on plastics and other nonconductive materials
- Suitable for use on zincated aluminum.