Hot compression deformation behavior and microstructural characteristics of high-purity silver

Abstract

High-purity silver (Ag) is extensively utilized in electronics, aerospace, and other advanced industries due to its excellent thermal conductivity, electrical conductivity, and machinability. However, the prohibitive material cost poses substantial challenges for optimizing thermal processing parameters through repetitive experimental trials. In this work, hot compression experiments on high-purity silver were conducted using a Gleeble-3800 thermal simulator. The high-temperature deformation behaviors, dynamic recovery (DRV) and dynamic recrystallization (DRX) of high-purity silver were studied by constructing an Arrhenius constitutive equation and developing thermal processing maps. The results show that plastic instability of high-purity silver occurs at high strain rates and the optimized hot processing parameters are the strain rate below 0.001 s⁻¹ and the temperature of 340–400 °C. Microstructural observations exhibit that DRV prefers to occur at lower deformation temperatures (e.g. 250 °C ). This is attributed to the low stacking fault energy of high-purity silver, which facilitates the decomposition of dislocations into partial dislocations and promotes high-density dislocation accumulation. Furthermore, DRX in high-purity silver becomes increasingly pronounced with increasing deformation temperature and reaches saturation at 350 °C.

Keywords

high-purity silver / deformation behavior / dynamic recovery / dynamic recrystallization / processing map / microstructural evolution

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