Silver plating is a favorite means employed throughout history to embellish base metal plate. The application of a layer of silver to iron or brass gave it the appearance of silver. As such, it was readily used by Roman coin counterfeiters as early as the 3rd and 4th centuries. Such plating is more familiar in the term silver- plated that is stamped on flatware and other items, including jewelry and art.
These early efforts at providing affordable and mass produced items for consumption did not involve the exact process finishers employ today. In fact, early flatware, as those produced in Sheffield, England, feature silver plating only on one side. It was not until the patented processes discovered by the Elkington Cousins -George Richards Elkington (1800-1865) and Henry (1810-1852), in the early to mid-1800s that electroplating became a reality. Further developments throughout the 20th century made the procedure more viable and safer for all involved.
Methods and Metals in Silver Plating
Silver plating is a process that is offered in several ways. Depending upon the intent, the substrate metal, and client’s preferences and, of course, the finishing company’s specialty, the method may consist of
- Barrel plating
- Rack fixture
- Wired
During the process, the choice of substrate may be any of a range of metals. Among the most commonly ones that are employed as a base are:
- Aluminum stainless steel alloys
- Brass
- Copper and copper alloys
- Stainless steel
- Stainless steel alloys
Why Many Manufacturers Prefer Silver Plating
Of all the reasons why manufacturers, particularly those in the electronics business, turn to silver plating is reduced to one major property – conductivity. Of all the known metals, the one with the highest level of both thermal and electrical conductivity is silver. By silver electroplating another metal, such as copper or brass, the base metal, or substrate, gains these properties. Nor is conductivity the only benefit that plating can provide.
Silver plating finds favor among many manufacturers because it:
- Has the lowest contact resistance of all metals
- Is less costly than gold plating while providing almost the exact benefits
- Is ductile and malleable
- Is more durable than gold
- Is toxic to a variety of microorganisms – this makes it excellent in the production of lab and other medical equipment
- Has spectral reflectivity
- Is corrosion resistant
- Exhibits improved solderability
- Provides greater lubrication
These physical and chemical properties are the basic reasons why medical, telecommunications and electronics industries prefer silver plating to other types of electroplating.
Silver Plating
This does not mean silver electroplating is without its flaws. Tarnishing, for example, is one issue. Yet, silver continues to be a popular metal for electroplating. Its superior properties combine together with its appearance, durability and corrosion resistance to make it a favorite among many industries. Add to this its relatively low cost and you can easily see why silver plating has become the norm for many applications.
