Effect of chemical composition and heat treatment on the microstructure and performance of Ag-based alloy wires
Yizhe Liu, Ling Shao, Shunle Zhang, Liepeng Hu, Yincheng Wu, Chengqing Liu, Yingqi Huang, Ping Le, Weiwei Li, Na Xue, Chenxiao Wang, Minghui Ye, Jianchun Li, Liu Zhu
Abstract
This study investigates the effect of Te addition combined with post-drawing heat treatment on the phase constitution, microstructure, microhardness, and corrosion behavior of Ag-based alloy wires. X-ray diffraction analysis revealed the formation of Ni 3 Sn 2 and Ag 2 Te intermetallic phases, while In was primarily dissolved in the matrix without the formation of detectable secondary phases. Optical microscopy and scanning electron microscopy observations showed that the as-drawn wires exhibited elongated grains and fibrous textures due to severe plastic deformation, accompanied by fine dispersions of second-phase particles. Heat treatment at 650 °C for 1 h facilitated static recrystallization, resulting in equiaxed grain structures and a redistribution of intermetallic phases. Energy dispersive X-ray spectroscopy analysis confirmed the presence of Ni 3 Sn 2 and Ag 2 Te phases. Microhardness measurements indicated an overall softening after heat treatment as a result of grain coarsening, although higher alloying levels provided moderate strengthening via solid solution and second-phase effects. Electrochemical testing demonstrated that increasing Sn, In, and Te contents reduced corrosion resistance, highlighting the trade-off between microhardness and corrosion performance. These findings provide insights for optimizing Ag-based alloys in applications requiring a balance between mechanical robustness and corrosion stability.