Abstract: Mo-Cu alloy was applied as the electrode material in thermoelectric (TE) device using CoSb₃based skutterudite compounds. Through adjusting the Cu content of Mo-Cu alloy, good thermal match between CoSb₃ material and Mo₅₀Cu₅₀ alloy was achieved. By means of spark plasma sintering (SPS), Mo-Cu alloy was successfully joined with CoSb₃ material through insertion of Ti layer. No crack was observed at the CoSb₃/Ti/Mo-Cu interfacial area showing the joints were well bonded. SEM shows that an intermetallic compound (IMC) layer forms at the CoSb₃/Ti interface and the IMC layer is identified as TiSb phase by the EDS analysis. After thermal aging, the thickness of TiSb phase increases. The high temperature reliability evaluation shows the joint has high thermal stability. The shear strength of joints decreases with the aging time increasing. The results of fourprobe measurement show that the interfacial resistance of joint is low and the contact electrical resistivity is 2030μΩ·cm², which means the CoSb₃/Ti/Mo-Cu joint exhibits a good electrical contact.

Key words: thermoelectric element, SPS, CoSb₃