Copper Nickel Alloy is mainly made of copper and nickel. The copper and nickel can be melted together no matter what percentage. Normally the resistivity of CuNi alloy will be higher if the Nickel content is larger than Copper content. From CuNi6 to CuNi44, the resistivity is from 0.1μΩm to 0.49μΩm. That will help the resistor manufacture choosing the most suitable alloy wire.