Also under these conditions en layers must be resistant.
P-rich layers are chemically more resistant than P-poorer layers. A cause for this is the phosphorus content and the different structure of the deposited layers.
Standards for the resistance and demand:
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Electroless nickel - chemical resistance of deposited layers
The chemical resistance is the resistance of a sufficiently thick, nonporous en coat in a usually liquid medium. It is independent of the ground material but nevertheless of the surfaces geometry. For this characteristic exists very much information - different medium contacts with the erosion rate in µm/year. Chemical resistance of Ni-P-layers are dependent of :
By corrosion resistance is to be understood the resistance of Ni-P-layers with layer thicknesses from few micrometers on a ground material in atmosphere or noxious gases and/or their mixtures. In contrast to the chemical resistance play here potential differences between ground material and coat an important role.
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