摘要
Phase equilibria information of the Ag-Se-Te ternary system is important as this system is used in thermoelectric applications. The Se and Te elements are the major constituents of many thermoelectric compounds, whilst the Ag element is widely used in the thermoelectric modules as an electrode. This study examines the reaction couples of Ag/Se, Ag/Se-30at%Te and Ag 2 Te/Se at 350 °C, as well as the isothermal section of the Ag-Se-Te system at 350 °C. There are five three-phase regions and no ternary compounds. The Ag/Se reaction couple shows the formation of the Ag 2 Se reaction layer with this phase having a very homogeneous composition. The reaction is very fast. The reaction layer is 550 µm thick in the couple reacting for 2 min. The Ag 2 Te/Se reaction couple shows the formation of Ag 2 Se, liquid, and Te-rich phases. The reaction path in the Ag 2 Te/Se reaction couple is Ag 2 Te/(Se,Te)/Liquid/Ag 2 Se/Se. It is found that the reaction layer is 576 µm thick in the couple reacting for 2.5 min. The Ag/Se-30at%Te reaction couple shows the formation of Ag 2 (Se,Te) and liquid phases. A very thick reaction zone of 2600 µm is found after reacting for 2.5 min. The related reaction paths and mass balances of the reaction couples are well explained using the determined isothermal section of the Ag-Se-Te system at 350 °C.