Sulfamate Nickel Plating (Company) per MIL-P-27418 & AMS 2424
Advanced Plating Technologies, a Milwaukee, Wisconsin company, provides low-stress, 99.9% high-purity sulfamate nickel plating to MIL-P-27218 and AMS 2424 as a subset of our functional applications in nickel plating. Sulfamate nickel plating excels where a highly ductile, low-stress nickel deposit is preferred such as flexing or crimping applications as well as joining functions such as soldering, brazing, epoxy bonding or welding.
Advanced Plating Technologies currently services a wide range of industries in sulfamate nickel plating including the interconnect, telecommunications, power transmission, medical and defense markets. Our company can precede the sulfamate nickel deposit with an underplate of copper plating if required and can provide sulfamate nickel plating as an underplate to final nickel deposits such as bright nickel plating or electroless nickel plating for duplex applications. Sulfamate nickel plating also serves as an excellent underplate for tin plating, silver plating and gold plating.
Sulfamate nickel plating is an electrolytic plating process first developed by Piontellil and Cambri in 1938. The primary difference in the sulfamate nickel plating bath is the use of nickel sulfamate rather than the nickel sulfate as is used in the traditional Watts nickel plating solution developed by Oliver Watts in 1916. It wasn’t until the mid-1950s and into the 1960s that sulfamate nickel plating became a commercially viable alternative to traditional Watts electrolytic nickel plating systems.
Sulfamate nickel plating produces a 99.9% pure deposit devoid of organic brighteners or levelers. The high purity of the deposit affords temperature resistance up to the 1400C+ melting point of pure nickel. The deposits have a full matte appearance with a slight yellow or golden cast not popular for decorative appeal. The deposits have extremely low deposit stress that can be in the compressive range. The low stress of sulfamate nickel plating yields nickel deposits with ductility, elongation and machinability far superior to other nickel deposits. If a bright ductile deposit is required, Advanced Plating Technologies proprietary Ducta-bright 7a nickel process is a better selection.
Sulfamate nickel plating excels in joining applications including brazing, soldering, over molding, epoxy bonding and welding. The high purity and lack of codeposited organics improves the wetting of the nickel deposit when soldering and makes sulfamate nickel plating the preferred underplate and diffusion barrier when tin plating, silver plating or gold plating for solderability or brazing. In addition, the unleveled matte surface makes sulfamate nickel plating the choice for adhesion in over-molding or epoxy bonding applications.x
The two most common sulfamate nickel plating specifications certified by Advanced Plating Technologies are MIL-P-27418 and AMS 2424. Our company also can certify our sulfamate nickel plating to QQ-N-290, ASTM B689 (Type 1) and ISO 1458 as well as most company-specific nickel specifications. A brief summary of some of the key aspects of sulfamate nickel plating per MIL-P-27418 and AMS 2424 is provided below:
Sulfamate Nickel Plating to MIL-P-27418
Plating, Soft Nickel (Electrodeposited, Sulfamate Bath)
3.3.3 Unless Otherwise specified, the plating shall be electrodeposited in an all-sulfamate, chloride-free nickel bath.
3.4.1 Plating Thickness: Unless otherwise specified, the plating shall be 0.002” +/- 0.0003” thick on all surfaces that can be touched by a ball 1/16” in diameter.
3.4.3 Knoop hardness of the plating after annealing shall not exceed 150 with a 500-gram load (300 Knoop before annealing).
Sulfamate Nickel Plating to AMS 2424
3.2.1 Nickel shall be plated from electrodeposition of nickel from a sulfamate solution or other suitable plating solution containing no additional agents… Except as permitted by 18.104.22.168 nickel shall be deposited directly on the basis metal without a prior flash coating of metal other than nickel.
22.214.171.124 Allows for preliminary underplates or strikes on “difficult alloys” such as corrosion resistant stainless steel, beryllium and their alloys or other similarly passive metals.
126.96.36.199 Where “Nickel Flash” is specified, plate thickness shall be approximately 0.0001 inch.
188.8.131.52.1 If internal surfaces are required to be plated to meet a thickness requirement, the drawing shall specify.
3.4.2 Hardness shall not be higher than 300 HV100 or equivalent.
3.4.3 Residual stress shall be within the range of 5 ksi in compression to 15 ksi in tension.
Sulfamate Nickel Plating Services – Why APT?
ASTM B689 (Type 1)
Most Company Specifications
Semi-Bright to Matte
Substrates Plated On:
Ferrous: All Ferrous Alloys Including Mild Steel, Stainless Steels, Hardened Steels & Tool Steels
Cuprous: All Cuprous Alloys Including Pure Copper, Copper Alloys Including Tellurium & Beryllium, Brass, Nickel-Silver
Aluminum: All Aluminum Alloys Including Wrought, Cast and Proprietary Alloys (MIC-6)
Exotics: Inconel, Pure Nickel (Nickel 200), Cobalt-Chrome (MP35N), Kovar, Monel, Hastalloy, Monel, Lead
Part Size Limitations: 32 Inches x 30 Inches x 12 Inches
Electroless Nickel (Aluminum Alloys)
Hydrogen Embrittlement Bakes
Stress Relieving Bakes
High Temperature Bakes up to 750F
Selective Loose Piece Plating
Sheet Product (Chemically Milled/Etched Sheets)
Segmented Strips (Frets)