Microstructure, precipitates and mechanical properties of Cu-3Ni-1Ti alloy by two-stage cold rolling and aging treatment

Abstract

The effects of two-stage cold rolling and aging treatment on the mechanical and electrical properties of Cu-Ni-Ti alloy were investigated. The microstructure evolution, precipitation behavior, and strengthening mechanism of the alloy after two-stage cold rolling and aging treatment were analyzed using microhardness, tensile strength, and electrical performance tests, combined with transmission electron microscopy (TEM) and electron backscatter diffraction (EBSD) techniques. The research results show that the alloy after two-stage cold rolling and aging treatment exhibits excellent comprehensive properties, tensile strength reaches 635 MPa, yield strength is 597 MPa, hardness is 182 HV, conductivity is 62.1 % IACS, and elongation is 14.5 %. This processing method facilitates the precipitation of more nanoscale Ni3Ti phases and the formation of smaller cellular substructures. Consequently, the alloy maintains its exceptional mechanical properties through the combined effects of dislocation and precipitation strengthening. This study provides a novel preparation process and a solid theoretical foundation for enhancing the mechanical and electrical properties of Cu-Ni-Ti alloys.