One-step Sintering of CoSb_3 Thermoelectric Material and Cu-W Alloy by Spark Plasma Sintering

摘要

In this study, we designed a suitable electrode material was designed, Cu-W alloy, which achieved a good thermal match with CoSb_3 thermoelectric (TE) material. By means of spark plasma sintering (SPS), Cu-W alloy was introduced into CoSb_3/Ti/Cu-W TE element successfully. Finite element analysis showed that the maximum thermal residual stress appeared at the cylindrical surface zone close to the CoSb_3/electrode interface. SEM and EPMA results showed that an intermetallic compound (IMC) layer formed at the CoSb_3/Ti interface and EDS analysis confirmed the IMC layer was TiSb phase. Shear tests showed that the shear strength of CoSb_3/Ti/Cu_(70)W_(30) joint was about 50Mpa. The potential profile of the interface area was measured by the four-probe method and the result showed no abrupt change in voltage was found around the interface. The high temperature reliability evaluation showed the joint had high thermal duration stability.