Effects of Zn Content on Microstructures and Hardness of Ag925CuZn Alloys

The effects of Zn content on the microstructures and hardness of Ag925CuZn alloys were systematically investigated. The experimental results show that alloying element Zn significantly reduced the porosity of the as-cast microstructure of Ag925CuZn alloys and induced their grains coarsening during intermediate annealing and led convex microstructure forming during aging, which possesses face center cubic solid solution α-Ag. Moreover, high Zn content led to the decrease of solution-annealed hardness and aged hardness of Ag925CuZn alloys. For Ag925CuZn alloys with low Zn content, their proper aging temperatures are between 200 °C and 250 °C after solution-annealing, and their proper aging temperatures are between 150 °C and 200 °C after cold rolling.