Metal finishing is a key aspect of the manufacturing process of any part. Although it can be tempting to attempt to save money by skipping this step, properly finishing a metal part is important not just for aesthetic reasons, but also to ensure that the part is able to properly resist corrosion and wear over time. The specific type of plating needed will depend heavily on your application, but if you are considering precious metal electroplating, then you will inevitably find yourself deciding between gold and silver.

What Is Electroplating?

Electroplating is a form of metal finishing that allows a very thin layer of a precious metal to be bonded to a non-precious substrate. Electroplating allows a part to be manufactured primarily out of a cheaper material while still benefiting from the advantages provided by a precious metal surface. The actual process of electroplating involves running a current through the part so that small amounts of the precious metal slowly bond to the surface through a process known as electrodeposition.

What Are the Advantages and Disadvantages of Silver Electroplating?

The number one advantage of silver when compared to gold is its lower price. Although electroplating with silver may still be a more expensive process than plating with a non-precious metal, it is drastically cheaper than plating the same part in gold.

Although it comes as a surprise to many people, silver also has the highest electrical conductivity of any metal—even higher than gold! Silver likewise has the highest thermal conductivity of all metals, while also being one of the most lightweight options available (although the small amount of material deposited through electroplating generally makes the weight of the plating material a non-issue).

Unfortunately, silver is not without its downsides. While silver is considered to be fairly resistant to oxidation, it will tarnish over time. This does not mean that silver is not durable, however, and tarnished silver can be polished to restore its finish.

What Are the Advantages and Disadvantages of Gold Electroplating?

The primary advantage of gold plating is its incredibly high resistance to corrosion. Gold is the best choice of plating material for applications where corrosion is a major concern, matched only by palladium in its resistance to oxidation. Gold is also an incredibly durable material, making it highly resistant to heat, moisture, and physical wear.

Unsurprisingly, the major downside to gold as a plating material is its cost. Generally speaking, only platinum is costlier as a plating material. Gold is also less conductive than both silver and copper, making it less desirable in situations where high conductivity is absolutely necessary. On the other hand, gold's near imperviousness to corrosion means that it will maintain its conductivity even when used in applications where silver or other metals would tarnish.