Creep behavior of unidirectional and angle-ply T800H/3631 laminates at high temperature and simulations using a phenomenological viscoplasticity model
Creep behavior of unidirectional and angle-ply T800H/3631 laminates at high temperature and simulations using a phenomenological viscoplasticity model
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单向和角层 T800H/3631 层压板在高温下的蠕变行为以及使用唯象粘塑性模型的模拟
DOI：
10.1016/j.compscitech.2004.04.004
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发表时间：
2004
期刊：
影响因子：
--
通讯作者：
Y. Masuko
中科院分区：
文献类型：
--
作者：
M. Kawai;Y. Masuko
研究了单向T800 H/3631碳/环氧复合材料对称角铺设层合板在较高应力水平下的高温蠕变行为。在载荷控制条件下，对[±30]3S、[±45] 3S和[±60] 3S三种角铺设层合板的普通试样进行了100 °C、5 h的恒应力拉伸蠕变试验。对于每个角铺设层压板，蠕变试验进行了三个不同的应力水平。在完全去除蠕变应力后，在相同温度下观察5小时蠕变后的蠕变应变恢复。在各种角铺设层合板中都能清楚地观察到蠕变响应。角铺设层合板的蠕变应变率随蠕变应变的增加而迅速消失。因此，无论纤维取向如何，在角铺设层合板中，瞬态蠕变都占主导地位。在去除蠕变应力之后，先前的蠕变应变不随时间完全恢复，这表明某些非弹性机制已经与蠕变一起操作。同样的复合材料系统的单向层合板的离轴蠕变行为也观察到类似的特征。一个完整的历史，包括先前的瞬时弹粘塑性行为在恒定应变速率和随后的蠕变响应在恒定应力水平下使用经典的层合板理论和现象学粘塑性模型的各个层进行模拟。基于单向层合板的离轴蠕变行为，确定了铺层粘塑性模型中的材料常数。它表明，通过额外考虑到变形引起的纤维旋转，得到的预测和观察到的结果之间的良好协议。
High-temperature creep behavior of symmetric angle-ply laminates made of unidirectional T800H/3631 carbon/epoxy composite is examined at relatively high stress levels. Constant-stress creep tests in tension are performed at 100 °C for 5 h on plain coupon specimens of three types of angle-ply laminates [±30]3S, [±45]3Sand [±60]3Sunder load control conditions. For each angle-ply laminate, creep tests are carried out at three different stress levels. Creep strain recovery following the 5-h creep is also observed for 5 h at the same temperature, after completely removing the creep stress. Creep responses are clearly observed in all kinds of angle-ply laminates. The creep strain rate in the angle-ply laminates tends to rapidly disappear as the creep strain increases. The transient creep is thus dominant in the angle-ply laminates, regardless of the fiber orientations. The prior creep strain does not completely recover with time after removing the creep stress, which indicates certain inelastic mechanisms have operated with creep. Similar features are also observed for the off-axis creep behavior of the unidirectional laminates of the same composite system. A whole history consisting of the prior instantaneous elastoviscoplastic behavior at a constant strain rate and the subsequent creep response at a constant stress level is simulated using the classical laminated plate theory and a phenomenological viscoplasticity model for individual plies. Material constants involved by the ply viscoplasticity model are identified on the basis of the off-axis creep behavior for unidirectional laminates. It is demonstrated that excellent agreements between the predicted and observed results are obtained by additionally taking into account the fiber rotation induced by deformation.