THE EFFECT OF Ag PRECIPITATES ON STRENGTH AND DUCTILITY OF CuAgZr ALLOY
Keywords:
Copper alloy, plastic deformation, precipitates, strengtheningAbstract
CuAgZr alloy is remarkably well-known for a good compromise between high strengthand high electrical conductivity. The strength is mainly contributed by the self-alignednanosized Ag precipitates on {111} planes in the Cu matrix. In this study, the evolution ofAg precipitates in Cu-7wt%Ag-0.05wt%Zr during thermal processing was characterizedto control the alloy microstructures in order to improve the mechanical strength andelectrical conductivity. The solution-treated CuAgZr alloy samples were cold rolled with alogarithmic strain of 2.3 and subsequently aged for various times. The X-ray diffractionand electron microscopy techniques indicate the evolution of precipitate size distributionduring different thermal routines and clarify that the change of dislocation density has adirect effect on Ag precipitation behavior and distributions. This paper discusses thecorrelation between the effect of plastic deformation and the evolution of nanoscale Agprecipitates, which provides the strength and electrical conductivity of this alloy.
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