Precious metal plating is an expensive process, especially because the standard method for improving corrosion is to increase the plating thickness. With self-assembled molecules (SAM’s), however, metal plating can be reduced significantly without losing corrosion protection. In addition to enhanced corrosion protection, SAM’s will also allow plated components to have increased conductivity.
Conductivity and Reduced Metal Thickness
Precious metal plated items, and in fact any plated item, experience increased resistivity because of uneven surfaces. This resistivity becomes even worse when the plating is thicker. Most manufacturers are forced to increase the thickness of the plating to stop corrosion, but this can decrease the performance of the item while increasing the cost of production. SAM’s addresses both of these issues. The molecular shield provided through SAM’s helps slow the corrosion process down and allows manufactures to use a thinner plating deposit.
When this happens, the conductivity of the plated item improves as well. This is because the plating is thinner and the molecular shield provides a more even surface that lowers resistance. Contact resistance due to uneven surfaces caused by thicker plating creates localized heating. With SAM’s, however, this problem is solved because the molecular shield fills the voids in any uneven surfaces of the plated component. The surface then becomes smoother, enhancing conductivity.
Wear Resistance and Reduced Metal Thickness
SAM’s allows manufactures to save money by reducing the amount of precious and semi-precious metals used to plate components. The question is however, “does using less metal make the item more vulnerable to wear and tear?” The answer is no, because SAM’s not only allows manufactures to save money, it also protects the surface of the plated components against repeated use.
SAM’s enhances the performance of the plated items even with reduced metal thickness because the molecular coating increases the lubricity and wear characteristics of the finished surface of the plated item. Testing lubricity can be difficult at times, and the only real way to know if plating can withstand wear and tear is to use it.
That’s why multiple lots went through the SAM’s process. The components then underwent a wear test to see just how much performance was enhanced. Components plated Gold (Au) over Nickel (Ni) over Copper (Cu) were tested in a universal micro-tribometer that used a 100-gram load with a 12.5mm motion at 30 hertz to create a controlled load and sliding motion on the surface tested.
At the conclusion of the test, the results showed; components plated with reduced thickness + SAM’s were far superior to components plated with higher thickness without SAM’s.
