Advanced Plating Technologies, a Milwaukee, Wisconsin silver plating company, offers functional silver plating services to QQ-S-365, ASTM B700 and AMS 2410, AMS 2411 & AMS 2412. Our company has expertise in providing precision barrel, rack and vibratory silver plating services and is currently employed in numerous industries including the medical, electric vehicle (EV), aerospace and electronics industries. Heavy build silver plating services up to 0.025” per side have been successfully provided by APT within the petrochemical and bearing industries.
APT offers a wide range of silver plating services including matte, semi-bright and bright silver deposits. Purities up to 99.9% pure are available with Type I, matte, 99.9% pure silver plating services available for wire bonding or defense applications. Our company has the ability to underplate with various nickel plating services including both bright electrolytic nickel, sulfamate electrolytic nickel and electroless nickel deposits as well as copper plating if required.
Inhibiting of silver plating services with RoHS compliant post plate chromates and triazoles are available. In addition, nitrogen backfilled, and sealed packaging is available to eliminate the potential for tarnishing of uninhibited deposits. Nitrogen bagging can extend the shelf life of silver plated products indefinitely ensuring low contact resistance and solderability at time of assembly when the packaging is opened.
Silver is an extremely ductile metal with a brilliant white luster. It has the highest electrical and thermal conductivity of all metals as well as the highest optical reflectivity in the visible range (gold plating is superior in the infrared range). Silver offers excellent high-temperature lubricity making it an excellent coating for anti-galling and anti-seizing applications on high temperature nuts and bearing surfaces with service temperatures up to 1200F. 99.9% pure, matte silver offers excellent solderability and wire bonding ideal for lead frames and circuit applications.
Silver has been known since ancient times for making jewelry and high-end utensils and is generally considered a precious metal. In reality silver is more properly designated a semi-precious metal due to the fact that it readily tarnishes, forming silver sulfide on the surface when exposed to air or water containing an oxidant and source of sulfur.
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
Underplates Provided:
Bright Electrolytic Nickel
Sulfamate Electrolytic Nickel
Electroless Nickel (High or Medium Phosphorous)
Copper
Tin, Lead or Tin/Lead
Heat Treatments:
Hydrogen Embrittlement Bakes
High Temp up to 750F
The most common silver plating services certified by Advanced Plating Technologies are QQ-S-365, ASTM B700 and AMS 2410, AMS 2411 and AMS 2412. APT can also certify our silver plating services to most company-specific silver plating specifications as shown in our specification database. A summary of silver plating services per the MIL, ASTM and AMS specs is as follows:
Silver Plating Services to QQ-S-365
Type I: Matte Deposits
Type II: Semi-bright Deposits
Type III: Bright Deposits
Grade A: With Supplementary Tarnish Application (Chromates)
Grade B: Without Supplementary Tarnish Application
3.3.5 Suitable Undercoat: The final silver deposit shall be preceded by an electrodeposited coating of silver from silver strike solutions. The plating shall be applied over an intermediate coating of nickel or nickel over copper on steel, zinc and zinc-base alloys. Copper and copper base alloys require intermediate coatings. Copper-alloy-basis metal articles on which a nickel undercoat is not used and other basis metal whereon a copper undercoat is employed shall not be used for continuous service at a temperature in excess of 149C (300F). Adhesion of the silver plating is adversely affected because of the formation by diffusion of a weak eutectic of silver and copper at the silver-copper interface.
3.4.1 Thickness of plating: Unless otherwise specified the minimum plating thickness shall be 0.0005 inch (0.013mm) on all surfaces on which silver is functionally necessary (for example: appearance, wear, corrosion protection, conductivity). The plating on nonfunctional surfaces and areas shall be of sufficient thickness to ensure plating continuity and uniform utility, appearance, and protection. On ferrous surfaces the total plated thickness shall be not less than 0.0010 inch (0.025mm). This must be comprised of at least 0.0005 inch (0.013mm) or more of silver plate over 0.0005 inch (0.013mm) or less of nickel or copper of any combination thickness of nickel and copper from 0 percent to 100 percent. The copper shall be deposited first over the steel surface.
Silver Plating Services to ASTM B700
Type 1: 99.9% Min Purity
Type 2: 99.0% Min Purity
Type 3: 98.0% Min Purity
Grade A: Matte Deposits – Deposits without the use of brighteners
Grade B: Bright Deposits – Deposits obtained with the use of brighteners
Grade C: Bright Deposits – Deposits obtained by mechanical or chemical polishing of Grade A coatings
Grade D: Semibright Deposits – Deposits obtained by the use of addition agents (grain refiners)
Class N – Without Supplementary Tarnish Application (Chromates)
Class S – With Supplementary Tarnish Application
Class T – A silver finish that has had a supplementary non-chromate treatment to resist tarnishing.
6.3.4 Underplating: A nickel or nickel-alloy intermediate layer, at least 1um thick, shall be applied before the silver electroplating when the product being plated is made from copper or copper alloy. Nickel underplating is also applied for other reasons.
3.2.1 Parts shall be plated in the following sequence except as permitted in 3.2.1.1, 3.2.1.2 or 3.2.1.3: Nickel Strike, Silver Strike, Silver Plate
3.2.1.1 The nickel strike may be omitted when plating copper and copper alloys
3.2.1.2 A gold or palladium strike may be used in place of the silver strike when approved
3.2.1.3 When approved by the cognizant engineering organization, silver may be plated directly onto the substrate without the use of either the nickel or silver strike.
3.3.2 Except as specified herein, all parts, except nuts, shall be heated to 935 to 965F (502 to 518 C) after plating, rinsing and drying and held at heat for 20 to 60 minutes…
3.4.1 Thickness – Thickness of silver shall be as specified on the drawing
3.4.1.1 Where silver flash only is specified, plate thickness shall be approximately 0.0001 inch (2.5um)
3.4.1.2 Thickness of plate, other than flash, shall be as specified on the part drawing.
3.4.2 Composition – Silver as plated, shall be not less than 99.9% pure…
Silver Plating Services – AMS 2411 – Plating, Silver for High Temperature Applications
3.2.1 Parts shall be plated using a three-step process: nickel strike, silver strike, and silver plate. The nickel strike shall be 0.0005 inch (13um) maximum. The use of organic base grain refining and brightener additives shall be prohibited in both the silver strike and silver plate solutions.
3.2.1.1 When approved by the cognizant engineering organization, an alternative to nickel strike is permitted.
3.4.1 Thickness of the deposit shall be as specified on the drawing…
3.4.1.1 Nickel strike shall not exceed 0.0005 inch (13um)
3.4.1.2 Where silver flash is specified, plate thickness shall be approximately 0.0001 inch (2.5um)
3.4.2 Composition of the deposit shall be not less than 99.9% silver determined by a method acceptable to the cognizant engineering organization.
3.2.1 Silver shall be plated over a preliminary plating of copper 0.0005-inch (13um) maximum. The copper strike may be omitted in plating copper and copper alloys, except for copper alloys containing zinc in quantities of 30% or more by weight. A nickel flash shall be used before the copper strike when plating corrosion-resistant steels.
3.3.2 Parts, except nuts shall be heated to 300-500F (149 to 260C) after plating, rinsing, and drying and held for not less than two hours, unless such heating would lower hardness to below drawing limits or otherwise deleteriously affect the parts, in which case heating shall be at the highest practicable temperature which will maintain specified properties. Thermal post treatment shall be in air, preferably in a circulating-air furnace.
