Viscosity and coefficient of thermal expansion (CTE) are both crucial properties in the design of new glasses for various applications. In this work, we extend the application of dilatometry to measure two important parameters governing the viscosity of glass‐forming systems, viz., glass transition temperature and fragility index. We also describe a method to determine the dilatometric fictive temperature (T _f,DIL) and present data for five unique glass compositions covering a range of fragilities spanning 38‐96, which are subjected to cooling and reheating rates in the range 1‐30 K/min. The results show that the glass transition temperature obtained from the dilatometric method at 10 K/min (T _g,DIL) is consistent with both viscosity‐based (T _g,vis) and DSC‐based measurements (T _g,DSC). It is shown that the fragility of a liquid (m _vis) can be determined by calibrating the dilatometric fragility (m _DIL) with the same empirical model as in the calorimetric approach. Put together, we have developed a reliable method to measure the fragility and predict the viscosity curves of glass‐forming liquids over a wide range (eg, 10¹‐10¹⁶ Pa·s) without direct viscosity measurements, while simultaneously obtaining the CTE of the glass. However, this method is not suitable for glasses with a strong tendency toward phase separation or crystallization.

中文翻译：

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膨胀玻璃的易碎性和粘度曲线的预测

粘度和热膨胀系数（CTE）都是设计用于各种应用的新型玻璃的关键属性。在这项工作中，我们扩展了膨胀计的应用，以测量控制玻璃成型系统粘度的两个重要参数，即玻璃化转变温度和脆性指数。我们还描述了一种确定膨胀测温（T _f，DIL）的方法，并提供了涵盖范围为38-96的脆性的五种独特玻璃成分的数据，这些成分经受了1-30 K范围内的冷却和再加热速率/分钟。结果表明，由膨胀法获得的玻璃化转变温度为10 K / min（T _g，DIL）与两种基于粘度的温度（T_g，vis）和基于DSC的测量值（T _g，DSC）。结果表明，可以通过使用与量热法相同的经验模型来校准膨胀脆性（m _DIL）来确定液体的脆性（m _vis）。综上所述，我们开发了一种可靠的方法来测量易碎性，并预测玻璃成型液体在较大范围（例如10 ¹ -10 ¹⁶  Pa·s）下的粘度曲线，而无需直接测量粘度，同时获得CTE值。玻璃。然而，该方法不适用于具有强烈的相分离或结晶趋势的玻璃。