Abstract The determination of in-plane coefficients of thermal expansion (CTEs) of full-stack composite laminates by means of thermo-mechanical analysis (TMA) is affected by free-edge effects. A numerical study has been performed, which is focussed on the quantification of the effects of TMA sample size, laminate layup and the presence of discrete interleaf layers on the determined laminate CTEs. Fine finite-element (FE) meshes have been used to visualize and to examine free-edge effects. The study results call for carefulness when CTEs of full multi-angle laminates shall be determined by means of TMA. When the typical sample dimensions of a few millimeter are used CTEs will likely be overestimated.

中文翻译：

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自由边缘效应如何阻碍复合层压板的 CTE 测定

摘要 利用热机械分析 (TMA) 确定全堆叠复合材料层压板的面内热膨胀系数 (CTE) 受到自由边缘效应的影响。已经进行了一项数值研究，其重点是量化 TMA 样本大小、层压板叠层和离散中间层的存在对确定的层压板 CTE 的影响。精细有限元 (FE) 网格已用于可视化和检查自由边缘效应。研究结果要求在通过 TMA 确定全多角度层压板的 CTE 时要谨慎。当使用几毫米的典型样本尺寸时，CTE 可能会被高估。