MIL-STD-868-SUP Nickel Plating, Low Embrittlement, Electro-DepositionThis standard covers the process and materials required for the electro-deposition of nickel on high strength steel substrates. Electro-deposited nickel is used for wear resistance, heat resistance, and as an undercoat for precious metals. Subsequent heat treating techniques needed to insure low hydrogen embrittlement of steel are also described. This standard meets the performance requirements of SAE-AMS- QQ-N-290 and may be used when SAE-AMS-QQ-N-290 is specified provided any unique requirements of SAE-AMS-QQ-N-290 are complied with.

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MIL-STD-868B

b.   Nickel Chloride c.   Nickel Sulfate

d.   Sulfamate Nickel Plating SN, Barrett Chemical Products

Division, Baltimore, MD or approved equivalent.

4.1.2   Equipment.

a.   Power source.  Either generated or rectified DC current may be used.  Ripple value shall not exceed 10 percent as measured by dividing the Root Mean Square of the AC voltage component by the DC voltage.  This can best be measured by using an RMS voltage meter and dividing this value by the DC voltage. These measurements are to be taken across the anode and cathode bus at the tank.

b.   Tanks.  Tanks should be resistant to the operating

temperature and the chemical environment.  Tanks in which any electrolytic action takes place must be free of short circuits.

c.   Temperature control.  Plating tanks to be operated at temperature other than room temperature shall be equipped with automatic temperature indicating and regulating devices.

d.   Instrumentation.   An ammeter shall be placed in series with the plating tank cathode.  The ammeter shall have sufficient shunts and switches to provide a full-scale reading equal to the maximum capacity of the power source and an accuracy of ± 10 percent of the current being measured.

e.   Blast equipment.  A blast cabinet shall be located near the plating line.  The size of the cabinet shall be adequate to enclose the parts to be plated. Air lines shall be suitably trapped and filtered to prevent in-process contamination of the parts to be cleaned.

f.   Bake oven.  An oven capable of baking parts at 191 ± 14'C (375 ± 25'F) shall be located near the plating line.  The size of the oven shall be adequate to enclose the parts to be plated.  The oven shall be equipped with temperature indicating, recording, and regulating devices.

4.2   Specification SAE-AMS-QQ-N-290.  The requirements of SAE-AMS-QQ-N-

290 shall be compiled with on all parts, in conjunction with those specified in this standard.  If there is a conflict between the two documents, the requirements of this standard shall govern.

4.3   Finish.  The plated part shall have a finish that is smooth, continuous, homogeneous, adherent, and free from pits, blisters, nodules and any other indications of harmful defects.

4.4   Shot peening.  All parts hall be shot peened in accordance with SAE-AMS- S13165 or MIL-R-81841 unless otherwise specified.

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