COATING OF COPPER WIRE

COATING OF COPPER

Sometimes bare copper is not enough to fulfill our requirement in that case we need to do coating of copper by other material. copper are mostly coated with tin(Sn),nickel,silver(Ag)

Tin-Copper

Tin is most common coating for the copper and copper alloys as cost of tin is low. Tin coating improve water resistance,chemical resistance,life time of wire,temperature range, and because solder is composed primarily of tin,tinned wire is easy to solder. But Tin has low conductivity, Therefore when tin plated over copper, it forms an inter-metallic layer which will increase resistance of wire. Tin coated wire can work upto 150°C

NOTE:-Bare Copper wire is known as Annealed Bare Copper(ABC) wire whereas Tinned Copper wire is known as Annealed Tinned Copper(ATC) wire

Nickel-Copper

Nickel is a much harder metal than any other common plating material therefore it provide excellent resistance to high temperature. It provide good corrosion resistance. But as the Melting point of nickel is greater than copper therefore soldering of a nickel plated wire is not easy and as conductivity of nickel is relatively Therefore when nickel plated over copper then there is increase resistance of wire. Nickel coated wire can work upto 300°C

Silver-Copper

Silver offers extremely high conductivity and reduce the resistance of wire. Silver coating wire is best for high frequency application because the skin effect will result in increased current flow through the silver layer. Silver coating wire will also work -65°C to 750°C.