| 摘要: | 近年來，大眾對環保議題愈加關注，加之能源枯竭，促使可再生和可持續循環利用的替代能源材料與綠能發電成為當前的研發重點。熱電材料是一種無污染且能在高溫環境下利用溫差直接將熱能轉換為電能，或將電能轉換為熱能的功能性材料，在能源轉換和冷卻技術中具有重要應用。但僅使用N型熱電材料無法達到預期效果，必須將N型與P型熱電塊材串接成熱電元件，確保在溫差下所產生的電壓為N、P型塊材個別電壓的總和，從而產生足夠的電能，然後再將多對元件組成模組。因此，研究的重點在於熱電塊材與電極之間在高溫下的接合方法和防止元素擴散。
在以往N型鎂矽錫熱電材料中混合不同鎂矽比例的基礎上，本實驗選擇了Mg2SnBi0.02+20at%Mg+4%MgSi作為熱電材料。我們使用了不同種類、厚度且具有低電阻率、高機械強度、良好熱穩定性並能與熱電試片產生適當反應的金屬材料作為接觸金屬。然後通過冷壓將金屬材料與鎂矽錫熱電材料接合，並進行600°C持溫1小時的退火處理。電性量測後，使用焊槍焊接、銀漿串接以及在試片表面鍍膜橋接金屬等方法進行串接。或是先將鎂矽錫粉末冷壓後加入接觸金屬和橋接金屬串接，再用石墨紙與鎳膠包覆後一起退火，並與N、P型低鎂矽錫粉末共同冷壓後退火等方法製作出N型低鎂矽錫塊材與P型低鎂矽錫塊材的熱電元件。根據各別元件的電性量測結果比較出最佳的串接方法，最後以此方法製作出熱電模組，並進行模組的電性量測。;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. |
