Thermal Shock Resistance Performance Of Thermoelectric Materials

With the continuous development and progress of science and technology,people's demand for new clean energy grows higher. Thermoelectric materials are class of materials which can convert thermal energy to electric energy. In practical applications, thermal stress built in the material due to thermal shock can lead to cracking of the materials. Accordingly, it is essential to investigate the fracture properties and the thermal shock resistance behavior of the thermoelectric materials.In this paper, the thermal shock analysis of single and laminated thermoelectric materials is carried out. The temperature field is solved by analytic method. The transient stress field is solved based on the constitutive equation and the force balance of the layer/layers. With taking Be2Te3 based thermoelectric material as an example, we discovered that the thermal stress is bigger in transient state. The maximal thermal stress occurs on the cool end of the single thermoelectric material layer. However, for multilayered thermoelectric materials, the maximum thermal stress occurs on the hot end. In addition, the stress intensity factor and thermal shock resistance are sensitive to the size of the materials. Stress intensity factor increases with increasing thickness of the materials. Thermal shock resistance reduces with increasing thickness of the materials. An empirical formula for the maximum thermal shock temperature the material can sustain is explored. The results of the thesis are useful for materials scientists and mechanical engineering for designing thermal resistive thermoelectric materials with good fracture mechanics performance.