Dynamic crushing of sandwich panels with prismatic lattice cores
Dynamic crushing of sandwich panels with prismatic lattice cores
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DOI：
10.1016/j.ijsolstr.2007.02.015
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发表时间：
2007-09
影响因子：
3.6
通讯作者：
M. Tilbrook;D. Radford;V. Deshpande;N. Fleck
中科院分区：
文献类型：
--
作者：
M. Tilbrook;D. Radford;V. Deshpande;N. Fleck
已经研究了不锈钢波纹和 Y 形框架夹层芯材的动态面外压缩响应，其冲击速度范围从准静态到 200ms−1。制造了相对密度为 2.5% 的实验室规模夹层芯，并使用直接冲击 Kolsky 棒测量了动态压缩夹层芯的正面和背面上的应力。为两种拓扑在冲击速度低于 30ms−1 时抵抗弹性屈曲的微惯性稳定性提供了直接观察证据。在较高的冲击速度下，芯构件内的塑性波导致正面应力随着速度的增加而增加，而背面应力保持大致恒定。虽然有限元计算以合理的精度预测背面应力和动态变形模式，但测量设备相对较慢的响应时间导致测量的正面应力和预测的正面应力之间的一致性较差。有限元计算还表明，材料应变率效应对实验室规模和全尺寸夹层芯材的动态压缩响应的影响可以忽略不计。
The dynamic out-of-plane compressive response of stainless steel corrugated and Y-frame sandwich cores have been investigated for impact velocities ranging from quasi-static to 200ms−1. Laboratory-scale sandwich cores of relative density 2.5% were manufactured and the stresses on the front and rear faces of the dynamically compressed sandwich cores were measured using a direct impact Kolsky bar. Direct observational evidence is provided for micro-inertial stabilisation of both topologies against elastic buckling at impact velocities below 30ms−1. At higher impact velocities, plastic waves within the core members result in the front face stresses increasing with increasing velocity while the rear face stresses remain approximately constant. While the finite element calculations predict the rear face stresses and dynamic deformation modes to reasonable accuracy, the relatively slow response time of the measurement apparatus results in poor agreement between the measured and predicted front face stresses. The finite element calculations also demonstrate that material strain-rate effects have a negligible effect upon the dynamic compressive response of laboratory-scale and full-scale sandwich cores.