摘要
为解决硫系玻璃在热加工和使用过程的稳定性判断等问题。通过熔融淬冷法制得Ge_(20)Sb_(15)Se_(65)玻璃,利用X射线衍射(XRD)和差示扫描量热仪(DSC)分别分析样品的结构和玻璃的特征温度,采用等温步阶法测定过冷液相和结晶相之间的比热差,通过比热计算吉布斯自由能和熵变,并绘制熵变曲线。根据Vogel-Fulcher-Tammann (VFT)方程拟合得到理想玻璃化转变温度。研究结果表明:样品的玻璃化转变温度、初始结晶温度和熔点分别为273.9℃、400.5℃和485℃,熔化焓为28.48 J·g^(-1)。拟合的理想玻璃化转变温度T_0为464 K,过冷液相和结晶相之间的比热差ΔC_p为0.096 9 J·K^(-1)·g^(-1)。过冷液相和结晶相之间比热差ΔC_p的测定结果为0.093 3 J·K^(-1)·g^(-1),与理论预测相近。根据熵变曲线图可以确定其Kauzmann温度T_k=506.7 K。
The paper discusses the stability criterion of chalcogenide glass in its hot processing and use.The Ge20Sb15Se65 glass was prepared by the melt quenched method.Its structure and characteristic temperature were analyzed by X ray diffraction (XRD) and differential scanning calorimetry (DSC).The specific heat between the supercooled liquid phase and the crystalline phase was determined by the isothermal step method.The Gibbs free energy and entropy change were calculated based on the specific heat and thus an entropy curve can be drawn.The ideal glass transition temperature was obtained by fitting according to the Vogel Fulcher Tammann (VFT) equation.The results are as follows.The glass transition temperature,initial crystallization temperature and melting point of the sample were 273.9 ℃,400.5 ℃ and 485 ℃,respectively,and the fusing enthalpy was 28.48 J·g ^-1 .The fitting ideal glass transition temperature T 0 of the sample was 464 K,and the specific heat difference Δ C p between the supercooled liquid phase and the crystal phase was 0.096 9 J·K ^-1 ·g^-1 .The specific heat difference Δ C p between the supercooled liquid phase and the crystalline phase was determined as Δ C p =0.093 3 J·K ^-1 ·g ^-1 ,similar to the theoretical prediction.According to the entropy curve,the Kauzmann temperature was determined as T k =506.7 K.
作者
高传磊
许军锋
刘振亭
王霞
坚增运
GAO Chuanlei;XU Junfeng;LIU Zhenting;WANG Xia;JIAN Zengyun(Shaanxi Province Key Laboratory of Photoelectric Functional Materials and Devices,Xi’an Technological University,Xi’an 710021,China)
出处
《西安工业大学学报》
CAS
2019年第2期185-190,共6页
Journal of Xi’an Technological University
基金
陕西省科技新星项目(2016KJXX-87)
陕西省教育厅项目(18JS050
16JK1380)
关键词
玻璃
比热
过冷液相
考兹曼温度
glass
specific heat
supercooled liquid phase
Kauzmann temperature
