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Ted Mooney, P.E. RET
Pine Beach, NJ
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for Metal Finishing since 1989
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Plating Nickel Cadmium Diffused
November 17, 2009
Hello, please someone with experience in this process.
I am working with nickel cadmium diffused, with
AMS2416; I have problems after the test of panel in Salt Spray ASTM
ASTM B117 B-117 it is present small point to corrosion; I adjustment concentration of solutions,
(degrease, activation, nickel, cadmium and conversion), density of current, time and rinse I can not eliminated to problem, This problem has diminished but I could have eliminated it.
Somebody can give me some advice of the possible causes the fails.
Note: The test panels are acceptable after test by thermal resistance.
Thanks.
Engineer - Mexico
November 24, 2009
Hello Maria,
If your plating thickness is correct for both metals, two possible causes could be adhered gas bubbles and solid particles causing pores or pits on the surface. Remedy for the bubbles would be to use an approved anti-pitting agent. For the particles, to improve filtration. But the problem could also come from plating too thin and/or not uniform across the entire surface. Saludos regios,
Guillermo F. Marrufo- Monterrey, Mexico
Monterrey, NL, Mexico
Hello Guillermo:
It verifies the thickness of nickel (0.002-0.0004 inch) and he is correct, the agent anti-pit this correct (verified), the bath has agitation by air and I have already in multiple occasions filtrated. We plating with nickel stainless steels and we do not have this problem, I think that is the form to activate the material, but I have until now not had good results, when inspecting the panels of test in stereoscope (100X approximately) I see small particles black however in the surface of the panel it does not have evidences of loosening in some zone of the panel, this phenomenon is not observed in the stainless steel panels because they is perfect.
Engineer - Mexico
December 1, 2009
December 9, 2009
Hi Maria,
At what point did you observe those black "particles" under the microscope, right after activation, after plating, after the diffusion treatment or after the salt spray test? Are they really particles or are they rather accumulated oxides?
G. Marrufo
Monterrey, NL, Mexico
Hello Guillermo:
The particles coke, the coke not produced the pitting on the nickel. The real cause of the problem after analyze all the stages of the process was the raw material. is very important verify the raw material,superficial condition, magnetisms, roughness and heat treating. At the moment the test panels is perfect.
thank you!
- MEXICO
April 30, 2010
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