The AMF Process

 

Specializing in industrial hard chrome plating serving the military automotive ground turbine nuclear power and machining and manufacturing industries

Since 1998 Allied Metal Finishing has been offering superior plating services for the industry exceeding customers expectations in quality and delivery, allied has grown to offer a one of a kind approach to hard chrome plating.

Allied Metal Finishing has the ability and experience to engineer, design, and develop precision tooling in order to accurately apply hard chrome to all of it’s customers supplied parts. With internal CNC milling, turning, welding, and casting departments. Allied Metal Finishing has the ability to “fine tune” needed fixture’s rapidly. With our well experienced staff at Allied Metal Finishing, we have been able to keep deliveries on schedule and costs reasonable.

While putting a new twist on a century old process, Allied Metal Finishing enjoys taking on some of the more difficult plating jobs, and turning them into reject free, high quality productions with electro polishing, nickel plating, vapor blasting and glass bead polishing.

Although we pride ourselves on our “Short Run Production Jobs”. Allied is proud to take on 1 piece jobs to 6 figure projects.

Utilizing high end measuring instruments, air gauges, micrometers, thickness testers and permascopes, Allied Metal Finishing prides our thorough inspection process, and ability to inspect virtually any job it takes in.

Thickness ranges from .000050 – .030
Capacities under 4 x 4 x 6 feet long
Weights as high as 1 ton.
Allied Metal Finishing is not only an approved & certified source for plating’s for many companies, but can meet and qualify for any approvals by contract. We take our jobs and our customers on professionally and personally. Please feel more than welcomed to contact Dan Traska or Dan Toce to discuss any quotes or needs involving your hard chrome plating.

 

 

The AMF Process

Chrome plating (less commonly chromium plating), often referred to simply as chrome, is a technique of electroplating a thin layer of chromium onto a metal or plastic object.

Chrome plating a component typically includes these stages:

  • Degreasing to remove heavy soiling
  • Manual cleaning to remove all residual traces of dirt and surface impurities
  • Various pretreatments depending on the substrate
  • Placement into the chrome plating vat, where it is allowed to warm to solution temperature
  • Application of plating current for the required time to attain the desired thickness

There are many variations to this process, depending on the type of substrate being plated. Different substrates need different etching solutions, such as hydrochloric, hydrofluoric, and sulfuric acids.Ferric chloride is also popular for the etching of Nimonic alloys. Sometimes the component enters the chrome plating vat electrically live. Sometimes the component has a conforming anode made from lead/tin or platinized titanium. Allied Metal Finishing has a typical hard chrome vat plate time at about 1 mil (25 µm) per hour.

     Hard chrome, also known as industrial chrome or engineered chrome, is used to reduce friction, improve durability through abrasion tolerance and wear resistance in general, minimize galling or seizing of parts, expand chemical inertness to include a broader set of conditions (especially oxidation resistance, arguably its most famous quality), and bulking material for worn parts to restore their original dimensions. It is very hard, measuring between 65 to 69 HRC.

Hard chrome tends to be thicker than decorative chrome, with standard thicknesses in nonsalvage applications ranging from 0.2 to 0.6 mm (200 to 600 µm), but it can be an order of magnitude thicker for extreme wear resistance requirements, in such cases 1 mm (1,000 µm) or thicker provides optimal results. Unfortunately, such thicknesses emphasize the limitations of the process, which are overcome by plating extra thickness then grinding down and lapping to meet requirements or to improve the overall aesthetics of the “chromed” piece. Increasing plating thickness amplifies surface defects and roughness in proportional severity, because hard chrome does not have a leveling effect. Pieces that are not ideally shaped in reference to electric field geometries (nearly every piece sent in for plating, except spheres and egg shaped objects) require even thicker plating to compensate for non-uniform deposition, and much of it is wasted when grinding the piece back to desired dimensions.

     Modern “engineered coatings” do not suffer such drawbacks, which often price hard chrome out due to labor costs alone. Hard chrome replacement technologies outperform hard chrome in wear resistance, corrosion resistance, and cost. Rockwell hardness 80 is not extraordinary for such materials. Using spray deposition, uniform thickness that often requires no further polishing or machining is a standard feature of modern engineered coatings. These coatings are often composites of polymers, metals, and ceramic powders or fibers as proprietary embodiment’s protected by patents or as trade secrets, and thus are usually known by brand names.

Hard chromium plating is subject to different types of quality requirements depending on the application; for instance, the plating on hydraulic piston rods are tested for corrosion resistance with a salt spray test.

 

Allied Metal Finishing is Located at. 379 Chapel Rd. South Windsor, CT. 06074. Phone (860)290-8865. Fax (860)290-8853


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