Cu₂Ni₅ is a copper-nickel alloy with a high nickel content, typically referred to in shorthand as Copper Nickel 2/5 or 2-5 CuNi alloy. The notation indicates an approximate composition of 2% copper and 5% nickel by weight, although exact compositions may vary slightly depending on the alloy's intended use. Used in connectors and components where moderate conductivity and non-magnetic properties are needed.

Cu₂Ni₅ offers good corrosion resistance, especially in marine and saltwater environments, which is typical for copper-nickel alloys. This makes it useful for applications exposed to moisture and chemicals.