Álvarez-Vázquez A, Fernández-Canteli A, Castillo Enrique, Pelayo F, Muñiz-Calvente M, Lamela M J
Department of Construction and Manufacturing Engineering, University of Oviedo, 33203 Gijón, Spain.
Royal Academy of Engineering of Spain, don Pedro 10, 28005 Madrid, Spain.
Materials (Basel). 2020 Apr 11;13(8):1809. doi: 10.3390/ma13081809.
Time and temperature, besides pressure in a lesser extent, represent the most significant variables influencing the rheological behavior of viscoelastic materials. These magnitudes are each other related through the well-known Time-Temperature Superposition (TTS) principle, which allows the master curve referred to relaxation (or creep) behavior to be derived as a material characteristic. In this work, a novel conversion law to interrelate relaxation curves at different temperatures is proposed by assuming they to be represented by statistical cumulative distribution functions of the normal or Gumbel family. The first alternative responds to physical considerations while the latter implies the fulfillment of extreme value conditions. Both distributions are used to illustrate the suitability of the model when applied to reliable derivation of the master curve of Polyvinil-Butyral (PVB) from data of experimental programs. The new approach allows not only the TTS shift factors to be estimated by a unique step, but the whole family of viscoelastic master curves to be determined for the material at any temperature. This represents a significant advance in the characterization of viscoelastic materials and, consequently, in the application of the TTS principle to practical design of viscoelastic components.
除了在较小程度上的压力外，时间和温度是影响粘弹性材料流变行为的最重要变量。这些量通过著名的时间 - 温度叠加（TTS）原理相互关联，该原理允许将参考松弛（或蠕变）行为的主曲线作为材料特性推导出来。在这项工作中，通过假设不同温度下的松弛曲线由正态或耿贝尔族的统计累积分布函数表示，提出了一种新的转换定律来关联不同温度下的松弛曲线。第一种选择基于物理考虑，而后者意味着满足极值条件。这两种分布都用于说明该模型在应用于从实验程序数据可靠推导聚乙烯醇缩丁醛（PVB）主曲线时的适用性。新方法不仅允许通过一个独特的步骤估计TTS移位因子，而且可以确定材料在任何温度下的整个粘弹性主曲线族。这代表了粘弹性材料表征方面的重大进展，因此，在将TTS原理应用于粘弹性部件的实际设计方面也有重大进展。
