Silver Plating: Practical Beauty
In the fairy tale of Snow White, the original mirror was probably not of glass but silver. Silver has long been a popular metal among many trades and crafts people. Silver plating, a more sophisticated approach, was also one that was quickly embraced by the same group of individuals. By using silver plating instead of solid silver, they were able to double their market. At the same time, they could retain the specific qualities that people sought from silver objects.
In today’s world, silver is more than a pretty bauble. It still provides the world with quality silverware and other decorative items, but its importance in the manufacturing world has gone far beyond the need to “Keep up with the Joneses.” As silver plating, this metal is prized for what it brings from the element table to less fortunate (and less expensive) substrate metals.
Desirable Properties through Silver Plating
One of the major reasons manufacturers turn to silver plating to cover copper and other substrate metals can be summed up in a single word – conductivity. Of all the known metals, silver has the highest thermal and electrical conductivity. At the same time, silver has the lowest contact resistance. Overall, this makes it ideal for use in the electronics industry.
Yet, other properties make silver plating attractive to other production facilities. These include both the medical and communication fields. Silver possesses the following making it appealing to various companies and production facilities:
* High thermal conductivity
* High electrical conductivity
* Toxic to several types of bacterial and diverse micro-organisms
* Wear resistance
* Spectral reflectivity
* Corrosion resistant
* Improved solderability
* Offers enhanced malleability
* Greater lubrication
These are all physical and chemical qualities afforded to a substrate through silver plating.
Silver Plating Baths
The most common type of silver plating bath consists of an alkaline cyanide solution. Modification of the bath produces the different types of depositions including:
* Matte: The preferred result unless appearance of the component or product is important. It is chosen for those projects that require good solderability and low electrical resistance
* Semi Bright: Resistant to fingerprints, this finish is more decorative than anything else, although it is also desired for its solid solderability
* Bright: This type of finish is suitable for those items requiring high electrical and/or thermal conductivity. It is also requested for applications that need such qualities as wear resistance and/or lubricity, solderability and optical reflectivity
If the right finish is to result, the finishers must employ the right bath and understand any necessary additives or precautions.
Silver has always been a popular metal. Its classification as precious owes as much to its history and mythology as to its qualities. In the past, it was the property of the wealthy. As coinage, jewelry and art, it became admired and sought after by those who had money. Electroplating changed availability. The discovery of how its properties could be beneficial to industry, mated with technology. The result portrays silver in a different light. While still decorative, silver plating now creates practical and functional articles available for all to admire and use.