Mechanical properties of Cu-Ni alloy thick films electrodeposited from aqueous solution containing pyrophosphate as a complexing agent

Cu-Ni alloy thick films with a thickness of approximately 170 µm were electrodeposited from an aqueous solution containing pyrophosphate as a complexing agent. The electrodeposited Cu-Ni alloy thick films with a dumbbell shape were exfoliated from a metallic titanium cathode to examine the crystal orientation, microhardness and tensile strength. The average crystallite size of electrodeposited Cu-Ni alloy thick films was around 30 nm. The microhardness increased up to 327 HV with increasing the Ni content up to ∼19 % while the maximum tensile strength reached 726 MPa at the Ni content of ∼13 %. The improvement of these mechanical properties can be explained by two strengthening mechanisms of solid solution alloying and crystallite size refining. • Cu-Ni alloy thick films with a dumbbell shape were electrochemically synthesized. • The average crystallite size of electrodeposited Cu-Ni alloy films was around 30 nm. • The microhardness increased up to 327 HV with increasing the Ni content up to ∼19 %. • The maximum tensile strength (726 MPa) was obtained from Cu-13 %Ni alloy films.