What are the challenges in plating high-phosphorus electroless nickel, with a phosphorus content of > 11% by weight? My understanding is that this type of electroless nickel is completely amorphous and pit free (and non-magnetic), offering the best corrosion protection. It also minimizes tool wear for diamond turning applications, compared to deposits of lower phosphorus content. Reportedly, it also offers the lowest levels of trace contaminants. Over the 10%-11% P range, there is transition from crystalline/magnetic to amorphous/non-magnetic. So, a > 11% P specification assures consistency. Yet my experience suggests that few job shops (platers) are capable (or even willing) to deposit such nickel. Why is it more difficult to plate > 11% P electroless nickel compared to > 10% P? MacDermid's websiteplating rates of 0.3-0.5 mil/hr for high phos. (10-13% P) compared to 0.6-1.0 mil/hr for mid phos. (5-9% P). Is plating rate the driving economic factor, or are there other factors that make the process difficult to establish and maintain?
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