| dc.description.abstract | In recent years, the public has increasingly focused on environmental issues. With the depletion of energy resources, the development of renewable and recyclable energy materials has become a primary research objective. Thermoelectric materials, which are non-polluting and capable of directly converting thermal energy into electrical energy or vice versa through sufficient temperature differences in high-temperature environments, have significant applications in energy conversion and cooling technologies. However, using only N-type thermoelectric materials is insufficient. It is necessary to connect N-type and P-type thermoelectric materials into thermoelectric devices, ensuring that the voltage under temperature differences is the sum of the voltages of the N-type and P-type thermoelectric materials. Multiple pairs of these devices can then form modules. Therefore, the research focuses on bonding techniques for thermoelectric block materials and preventing element diffusion at high temperatures.
For this experiment, the chosen thermoelectric material is Mg2SnBi0.02+20at%Mg+4%MgSi, based on previous studies that explored different ratios of magnesium and silicon in N-type magnesium-silicon-tin materials. To make electrical connections, various metal materials with low resistivity, high mechanical strength, and good thermal stability were cold-pressed together with the thermoelectric materials and annealed at 600°C for one hour. Different connection methods, including welding, silver paste connection, and sputter-bridging of metals on the specimen surface, were used. Additionally, magnesium-silicon-tin powder was cold-pressed, contact metals and bridging metals were added for connection, and the specimen was covered with graphite paper and nickel adhesive before annealing. N-type and P-type low magnesium-silicon-tin thermoelectric elements were produced by co-cold-pressing and annealing N-type and P-type low magnesium-silicon-tin powders. The optimal connection method was determined, and a thermoelectric module was created and measured. | en_US |