CAJ | 학술논문

分别采用热压、低电场强度和高电场强度3种工艺烧结制备Bi1.2Sb4.8Te9热电材料,测试、对比分析3组试样的微观结构和热电传输性能。结果表明,采用电场加热方式烧结可有效提高材料的致密度,且在大电场强度工艺下晶粒择优取向。电场可使材料内缺陷减少,载流子浓度下降,同时提高载流子迁移率,使材料综合电性能提高,晶粒择优取向有助于降低材料热导率,这些都有助于热电材料ZT值的提高。
분별채용열압、저전장강도화고전장강도3충공예소결제비Bi1.2Sb4.8Te9열전재료,측시、대비분석3조시양적미관결구화열전전수성능。결과표명,채용전장가열방식소결가유효제고재료적치밀도,차재대전장강도공예하정립택우취향。전장가사재료내결함감소,재류자농도하강,동시제고재류자천이솔,사재료종합전성능제고,정립택우취향유조우강저재료열도솔,저사도유조우열전재료ZT치적제고。
Thermoelectric materials Bi1.2 Sb4.8 Te9 was sintered under three different conditions including no-cur- rent sintering (NCS), low-current density sintering (LCS) and high-current density sintering (HCS). The mi- crostructure and thermoelectric performance of three groups' samples were tested and compared. The results indicated that the applying of electric current in the sintering process can significantly improve the densifieation of samples, and the large electric field can make the grains oriented at the direction of the electric field. The e- lectric field can eliminate crystal defects, and decrease the carrier concentration, and increase the carrier mobili- ty. Thus the power factor was enhanced. The preferred orientation of grains can decrease the thermal conduc- tivity. Therefore, a large electric field and high electric current in the sintering process may be the effective way to obtain thermoelectric materials with high value of the figure of merit ZT.