Copper Nickel 90/10 type of washers are made with roughly 90% copper and 10% nickel along with very small amounts of iron and manganese used to improve overall strength and help resist corrosion. Copper Nickel 90/10 has excellent resistance to seawater, chloride-induced stress, and biofouling. Therefore, it is useful in many marine applications. Mechanical Properties: Copper Nickel 90/10 washers have moderate mechanical strength, with typical tensile strengths between approximately 310 and 380 MPa; yield strengths are typically between 120 and 150 MPa. These washers exhibit good ductility (40% elongation), and they have a hardness between approximately 80 and 120 HB; therefore, they are suitable for use as durable, effective fasteners in corrosive and demanding environments.
