White bronze, also known as "tri-metal" or "ternary-alloy" in the context of plating, is an alloy composed primarily of copper, tin, and zinc. Although the exact composition can vary, it's generally around 55-60% copper, 20-25% tin, and 20-25% zinc (CuSnZn3).
White Bronze Plating
White bronze gets its name from its shiny, silver-like appearance. Despite its name, it doesn't actually contain any bronze, which is an alloy of copper and tin. The addition of zinc and the specific ratios of the three components give white bronze its distinct properties and appearance.
In the field of RF and telecommunications, white bronze is often used as a plating material for connectors and other components. It's a popular choice because it offers a good balance of electrical performance, corrosion resistance, and cost-effectiveness.
White bronze exhibits lower electrical conductivity compared to silver or gold, but its resistance to tarnish and corrosion is excellent. It also delivers decent performance at high frequencies and maintains a low level of passive intermodulation (PIM), making it suitable for high performance telecommunications applications.
Another advantage of white bronze is its compatibility with other metals. Unlike silver, which can experience galvanic corrosion when in contact with different metals, white bronze can be mated with various other metals without the risk of galvanic corrosion.