Mechanical Properties of Electrodeposited Cu–Sn–Ni Alloy Films

Cu-Sn-Ni ternary alloy thick films were electrodeposited from a basic complex bath containing potassium pyrophosphate. The crystal orientation and physical properties such as microhardness and tensile strength were evaluated. The addition of potassium pyrophosphate formed complexes with Cu2+, Sn2+, and Ni2+ ions in aqueous solution, and the electrodeposition potential was shifted to a less-noble direction. The maximum hardness (431 HV0.1) was obtained from the Cu-4.9%Sn-0.9%Ni alloy film while the maximum tensile strength (1036 MPa) was achieved with the Cu-2.4%Sn-0.3%Ni alloy film. These mechanical properties were enhanced by the solid solution of Sn and grain refinement.