Effect of annealing on microstructure and properties of cold-rolled Cu-Ag alloy

doi:10.13251/j.issn.0254-6051.2022.08.021

Abstract

Abstract: Effect of annealing on microstructure, mechanical properties and electrical properties of the Cu-24%Ag alloy was studied by means of scanning electron microscope, transmission electron microscope, tensile testing and thermoelectric performance analysis system. The conduction mechanism of the alloy was studied by constructing an electron interface scattering model. The results show that the microstructure of the Cu-24%Ag alloy is effectively controlled by annealing, and the comprehensive properties are improved. The tensile strength of the alloy decreases to 95% of that of the cold-rolled alloy and the conductivity increases by 4%IACS after annealing at 350 ℃ for 1 h. After annealing at 450 ℃ for 1 h, the tensile strength decreases significantly and is only about half of that of the cold-rolled alloy due to the dissolution of Ag fibers. In addition, the dissolution of Ag fibers reduces the scattering probability of electrons and improves the conductivity. Therefore, the Cu-24%Ag alloy annealed at 350 ℃ for 1 h has the best comprehensive properties, of which the tensile strength and conductivity are 622 MPa and 81%IACS, respectively.

Key words: Cu-Ag alloy, annealing treatment, microstructure, strength, conductivity

CLC Number:

TG166.2

Chen Jianlan, Zhao Modi, Han Fusheng. Effect of annealing on microstructure and properties of cold-rolled Cu-Ag alloy[J]. Heat Treatment of Metals, 2022, 47(8): 129-134.

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