文章信息/Info

Title:

Effect of Spark Plasma Sintering on Sintering Process of Filled Skutterudites Thermoelectric Properties

作者:

周振興1; 陸曉芳1; 王連軍1; 2; 顧士甲2; 3

1.東華大學材料科學與工程學院 纖維材料改性國家重點實驗室，2.東華大學 先進玻璃制造技術教育部工程研究中心3.東華大學 東華大學功能材料研究所

Author(s):

ZHOU Zhenxing1;  LU Xiaofang1;  WANG Lianjun1; 2;  GU Shijia2; 3

1.State Key Laboratory for Modification of Chemical Fibers and Polymer Materials & College ofMaterials Science and Engineering, Donghua University, 2.Engineering Research Center of Advanced Glasses Manufacturing Technology, Ministry of Education,Donghua University, 3.Institute of Functional Materials, Donghua University,

關鍵詞:

熱電材料; 等離子體快速燒結; 填充方鈷礦; 高能球磨; 微納結構; 燒結工藝

Keywords:

thermoelectric material;  spark plasma sintering;  filled skutterudites;  high-energy ball milling;  micro/nano structure;  sintering process

DOI:

10.7502/j.issn.1674-3962.201706007

文獻標志碼:

A

摘要:

采用熔融淬火和高溫退火法合成填充方鈷礦Yb0.3Co4Sb12塊體，用高能球磨的方法將已經填充的方鈷礦研磨為微納米級粉末，然后采用等離子體快速燒結（SPS）技術將其燒結成塊體材料。通過XRD分析材料的物相結構，使用SEM和TEM觀察粉體和塊體材料的微觀形貌，發(fā)現(xiàn)高能球磨后的晶粒尺寸為50~500 nm，分布較寬。重點研究討論了燒結溫度和燒結壓力等燒結工藝對熱電傳輸性能的影響：發(fā)現(xiàn)隨著燒結溫度的提高，材料的熱電性能先升高后降低，這是由于燒結溫度的升高使得樣品致密度有效提高，引起材料熱電性能提升，而過高的燒結溫度造成材料晶粒異常長大導致材料的熱導率提升，熱電性能劣化；提高燒結壓力可以略微提高樣品的致密度與熱電性能。研究發(fā)現(xiàn),當燒結溫度約為875 K、燒結壓力約為90 MPa時，材料的熱電性能最佳，熱電優(yōu)值（ZT值）在750 K時達到1.19。

Abstract:

In this study, filled skutterudites Yb0.3Co4Sb12 were synthesized by meltting quenching and annealing method. Then high-energy ball milling was employed to prepare micro/nano�瞫tructured powders. After that bulk materials were sintered by the technology of spark plasma sintering (SPS). The phase structure and morphology of the powder and the bulk materials were studied by XRD, SEM and TEM. The grain size after high-energy ball milling was 50~500 nm and the distribution is wide. The thermoelectric properties of the samples with different sintering processes like sintering temperature and sintering pressure were investigated in detail. The results show that with the increase of sintering temperature, the thermoelectric properties first increase and then decrease, which is caused by the increase of the sample density first and then the grain growth. And the densities and thermoelectric properties can be improved slightly by increasing sintering pressure. After sintered at about 875 K with 90 MPa, the thermoelectric properties of the material are the best, and the thermoelectric figure of merit (ZT value) reached 1.19 at 750 K.