Change is in the air
Humans discovered that if another metal was mixed with copper, it changes its properties for the better. That led to several alloys being discovered. Bronze, a copper alloy, is a mix of copper and tin and brass is a mix of copper and zinc.
These alloys were much stronger than copper alone. Also, they could be more easily cast. This opened a whole new world where copper could be played around with to make it more usable for different applications. Copper is used in various forms such as bare cables, wires, bars, Braided Flexible Connectors, and more in various fields.
Copper turns green when it is exposed to the air. A famous example of oxidized copper is the Statue of Liberty. The colour change may not have been an issue, but the oxidation is a semi-conductor, which on top of an excellent conductor like copper is not good news.
To control the issue of oxidation in copper, a method was found where covering bare copper strands with tin helped immensely. Apart from saving it from oxidation, it also added durability to it along with longevity.
Covering copper with tin
One way of preventing oxidation is to cover copper with something, usually plastic, to eliminate contact with air since no air means no oxidation. However, the minute the cover goes off, oxidation will occur. The answer to this is soldering the copper in. Once that is done, air does not get near the base copper strand, leaving it resistant to oxidation.
There are two methods that can be followed to cover copper wires in tin. One way to do that is by dipping the strands in hot molten metal so that they are covered completely. This is called the ‘Hot Dipping’ method. The other method is electroplating. An electric charge is passed through the strand which allows tin to stick to it and cover it completely.
The biggest advantage of tinning is that it adds to the shelf life of copper. Copper’s natural strengths are boosted several times over, and it is believed that tinning amplifies copper’s longevity by ten times.Connectivity of copper is also enhanced since tin is a primary soldering component. The tinning process makes copper almost impervious to high humidity conditions, wet environs, and high temperatures.
Tinned copper is used extensively in many applications, even high-risk ones such as in the marine electrical arena. It can be safely said that tin coated copper wire is much better that bare copper wire.