Effect of trace alloying elements on stress relaxation properties of high strength and high conductivity C19160 alloy

The addition of Si in a Cu-Ni-P-Pb P -Pb (C19160) alloy has been fabricated by atmospheric smelting to approach high strength, high conductivity, and high-stress relaxation resistance. The addition of Si inhibited the coarsening and phase transition of Ni5P4. 5 P 4 . The fine Ni5P4 5 P 4 particles were dispersed in the matrix, which pinned dislocations and improved the studied alloy's strength and stress relaxation resistance. After homogenization at 900 degrees C for 4 h, cold rolled by 70 %, aging treatment at 450 degrees C for 1 h, cold rolled by 60 %, aging treatment at 400 degrees C for 45 min, cold rolled by 60 %, annealing treatment at 200 degrees C for 1 h, the C19160-0.1Si alloy shows an ultimate tensile strength of 705 MPa, electrical conductivity of 53.8%IACS, and a stress relaxation rate of 17.8 % after tested at 150 degrees C for 100 h. These findings have guiding significance for developing C19160 alloys with high strength, high conductivity, and high-stress relaxation resistance.