Applicators of nickel-phosphorus coatings using electroless nickel technology have been putting up with short bath life for years. A significant factor in the use of electroless nickel coating systems has been the need to discard the bath or at least dilute it significantly on a regular basis; this is done to remove the build up of reducer breakdown products and sulphates. These are both by-products and additives found in the system that limit the bath life. Most often bath life ends when a specific gravity of around 1.300 is reached (1.3 gm/cm~3) giving roughness or precipitation/decomposition or when internal tensile stress levels in the coating increase to give problems of poor adhesion.
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