DSC Method for Determining the Liquidus Temperature of Glass-Forming Systems
DSC Method for Determining the Liquidus Temperature of Glass-Forming Systems
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DOI：
10.1111/j.1551-2916.2010.03976.x
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发表时间：
2010-11-01
影响因子：
3.9
通讯作者：
Zanotto, Edgar D.
中科院分区：
文献类型：
--
作者：
Ferreira, Eduardo Bellini;Lima, Moyses L.;Zanotto, Edgar D.
我们开发并成功测试了差示扫描量热法 (DSC)，以估计良好的玻璃形成系统（即难以结晶的系统）的液相线温度 (T(L))。该方法首先针对几种 Li(2)O-B(2)O(3) 玻璃进行了测试。测量 DSC 熔化峰的起始温度、峰值温度和终点温度，并与相平衡图中的液相线进行比较。 DSC 运行在不同的加热速率下进行，平衡时的 T(L) 通过外推至 0 摄氏度/分钟来估计。对于在典型 DSC 运行期间不结晶的玻璃，需要预先进行热处理以诱导结晶。然后通过 DSC 获得三种多组分玻璃的液相线，并与使用光学显微镜直接技术获得的 T(L) 进行比较。以不同速率测量并外推至 0 摄氏度/分钟的 DSC 熔化峰终点是此类玻璃液相线的最佳估计。大多数结果相差不超过 10 摄氏度。由于所需玻璃量小、仪器检测的可能性、许多不同成分的同时结晶预处理以及 DSC 分析的速度，所提出的技术可能是估计简单或复杂多组分玻璃液相线的有价值的选择。
We developed and successfully tested a differential scanning calorimetry (DSC) method to estimate the liquidus temperature (T(L)) of good glass-forming systems, i.e., that are reluctant to crystallize. The method was first tested for several Li(2)O-B(2)O(3) glasses. The onset, peak, and endpoint temperatures of DSC melting peaks were measured and compared with the liquidus in the phase equilibrium diagram. DSC runs were carried out at different heating rates and T(L) at equilibrium was estimated by extrapolation to 0 degrees C/min. For glasses that do not crystallize during a typical DSC run, a previous heat treatment was necessary to induce crystallization. The liquidus of three multicomponent glasses were then obtained by DSC and compared with the T(L) obtained by a direct technique using optical microscopy. The endpoint of the DSC melting peaks measured at different rates and extrapolated to 0 degrees C/min was the best estimate for the liquidus of such glasses. Most results differ by not more than 10 degrees C. Because of the small amount of glass needed, the possibility of instrumental detection, simultaneous crystallization pretreatment of many different compositions, and the speed of the DSC analysis, the proposed technique may be a valuable option to estimate the liquidus of simple or complex multicomponent glasses.