Silver - Silver is quite soft and malleable (easily shaped).. With the exception of gold, it is the most malleable and ductile (able to be drawn into very thin wire) of all metals. Silver is harder than gold but softer than copper. It is quite resistant to corrosion and does not oxidize easily.
Of all the metals, it is the best conductor of electricity. When silver is plated over copper there can be an accelerated corrosion of the copper at pinholes or breaks in the silver plating. It is then susceptible to the formation of cuprous oxide when stored or used in a moist or high humidity environment. The corrosion is known as "red plague" and is identifiable by the presence of a brown-red powder deposit on the exposed copper.
Due to this possible corrosion, it may be wise to consider an insulation over the silver-plated copper wire, such as Teflon. Silver plated copper wire has applications in the medical field. Silver plating over oxygen-free copper reduces the resistance of the copper, thus enhancing audio and video cables and wires. Silver plated Copper wire is available with different plating thickness from 5 - 200 g silver / kg of wire. Silver plated Copper wire is available in diameters from 0.020mm to 0.500mm (AWG 52-24) with all insulations and self-bonding enamels. We also make Bare Silver Plated Wire.
Gold - Gold is soft and wears easily, so it is often mixed with harder metals. Gold is un-reactive, which means it is resistant to corrosion and tarnishing, at high or low temperatures. Gold is also malleable and ductile. Gold is a very good conductor of electricity and, since it can be drawn into very thin wires, has many applications in electronics.
Gold plating on contacts for switches, relays and connectors accounts for most of the gold required each year by the electronics industry. Gold Plated Copper Wire is used in satellites as part of their electronic circuits and as a heat shield. Copper with gold or silver plating can be used in the ultra flexible and ultra miniature wire needed in instrumentation used in the medical industry.
Palladium - Palladium/Nickel Alloy and Pure Palladium Plating provide many of the same positive qualities as gold, including comparable connectivity and wire bonding characteristics. Similar to gold, palladium does not oxidize or chemically react in corrosive environments. However, these materials are less dense than gold, which means fewer Palladium/Nickel Alloy and Pure Palladium Plating resources are used to achieve equal linier thickness.
Because it's harder than gold, palladium plating can have better wear attributes and may be less sensitive to process fluctuations. It creates low surface contact resistance, making Palladium ideal for applications that require contact surfaces for soldering or wire bonding. The density of pure palladium and palladium/nickel alloy electroplating allows these materials to withstand high heat from reflow applications while still bonding wire and maintaining solderability. It is also an excellent choice when a project requires a barrier between base metals such as nickel or copper and gold.
Nickel - nickel plated copper wire is composed of a copper core, covered by a concentric nickel plating. Some advantages of the nickel layer include high corrosion resisitance, as well as, outstanding mechanical properies. Another advantage to magnetic nickel plating is the reduction in high frequency lost in HF applications.