General Properties of Electroless Nickel Plating
Semi-bright appearance similar to polished stainless steel. Electroless Nickel covers complex geometries with a uniform layoer of nickel-phosphorus alloy. Electroless Nickel out-performs "regular" nickel in corrosive environments and provides better wear resistance.
Low (2-4%) Phosphorus Electroless Nickel
Low phosphorus electroless nickel offers the highest level of solderability and electrical conductivity. It is highly resistant to alkaline environments. Low-P EN can be heat treated to a Knoop hardness of about 1000, while the "as-plated" deposit has a Knoop hardness of 620-750. This translates to Taber wear numbers of 2-4 mg/1000 cycles. After heat treatment these taber values change 1-2mg/1000 cycles.
Medium (5-9%) Phosphorus Electroless Nickel
The medium phosphorus electrocless nickel have an "as-plated" hardness range of 450-500HK. Such deposits are not as solderable as the low phosphorus electroless nickel deposits, and may require an agressive flux. Med-P EN deposits offer better corrosion resistance than low-P EN. Deposits containing more than 7%P have very low levels of magnetism. The wear resistance of these alloys falls into the 15-18mg/1000 Taber cycles range in the as-plated condition and 4-8mg/1000 cycles after heat treatment.
High (>10%) Phosphorus Electroless Nickel
High-P EN deposits offer the highest level of corrosion resistance and are considered to be non-magnetic for most all purposes. These deposits should not be used when a high level of solderabi lity is required. These alloys offer an "as plated" hardness* range of 450-500 VHN100. Taber wear t esting has yielded weight losses of 16-18 mg/1000 cycles for the as plated deposit.