The glass-forming ability of binary GexTe100-x (x=15, 20, 30) alloys was investigated. The crystallization mechanism of these amorphous bulks was studied by X-ray diffraction (XRD), scanning electron microscopy (SEM) and differential scanning calo- rimetry (DSC). The temperature of glass transition, the temperature of crystallization, the activation energy for glass transition and crystallization, and the order of the crystallization mechanism were calculated from the different heating-rates.
Feng Yan1), Tiejun Zhu1), Xinbing Zhao1), and Shurong Dong2) 1) State Key Laboratory of Silicon Materials, Department of Materials Science and Engineering, Zhejiang University, Hangzhou 310027, China 2) Department of Information and Electronics Engineering, Zhejiang University, Hangzhou 310027, China
Zr1-xTixNiSn0.975Sb0.025 (x=0, 0.15, 0.25, 0.5) half-Heusler thermoelectric materials have been prepared by levitation melt, melt spinning and hot pressing. X-ray diffraction analysis and scanning electron microscopy observation showed that nearly single phase half-Heusler compounds were obtained for the levitation-melted ingots. The effects of Ti substitution and grain refinement by melt spinning have been studied. It is found that both the Ti substitution on the Zr site and the grain refinement can reduce the lattice thermal conductivity and total thermal conductivity. The maximum figure of merit ZT value achieved is about 0.47, which is comparable with the previously reported value of ～0.5 for Zr0.5Ti0.5NiSn.
Cui Yu Yun Zhang Tiejun Zhu Guangyu Jiang Ji Xu Bo Zhao Xinbing Zhao
