首页> 外文期刊>Composite Structures >Temperature effect on non-stationary compressive loading response of polymethacrylimide solid foam
【24h】

Temperature effect on non-stationary compressive loading response of polymethacrylimide solid foam

机译:温度对聚甲基丙烯酰亚胺固体泡沫非稳态压缩载荷响应的影响

获取原文
获取原文并翻译 | 示例
           

摘要

This paper presents the results of experimental investigation and modeling the polymethacrylimide (PMI) solid foam response on slightly non-stationary compressive loads at different loading speed and temperature. The PMI represents a typical material used as a core component of composite sandwich structures. For all conditions, the strain-stress curves exhibit three definite regions, such as linearly elastic, plateau, and densification as it is known from the literature. However, it is shown in the present study that even minor fluctuations of the loading speed may lead to significant qualitative effects within the plateau segment. In particular, spike-wise load drops occur in a regular way during the loading phase when the specimen temperature is below -20 ℃. Acoustic emission tests lead to the conclusion that the load drops are associated with generation of brittle fractures in the clusters of broken foam cells. Also, cyclic loading tests were conducted to evaluate the energy loss in cells permanent deformation during the loading cycle. The amount of energy dissipated for each cycle is reduced at higher temperatures. Finally, based on the experimental results, a phenomenoiogical model of the foam load-displacement response at different loading speeds and temperatures is presented in the form of a single analytical expression.
机译:本文介绍了实验研究的结果,并模拟了聚甲基丙烯酰亚胺(PMI)固体泡沫在不同加载速度和温度下对轻微非平稳压缩载荷的响应。 PMI代表用作复合夹心结构核心组件的典型材料。在所有情况下,应变-应力曲线都显示三个确定的区域,例如线性弹性,平稳和致密化,这是从文献中得知的。然而,在本研究中表明,即使加载速度的微小波动也可能导致高原段内明显的定性影响。特别是在样品温度低于-20℃时,在加载阶段会定期出现尖峰载荷下降。声发射测试得出的结论是,负荷下降与破裂的泡沫细胞簇中的脆性断裂的产生有关。此外,进行了循环加载测试,以评估在加载周期中单元永久变形中的能量损失。在较高温度下,每个循环耗散的能量减少。最后,基于实验结果,以单个解析表达式的形式给出了在不同加载速度和温度下的泡沫载荷-位移响应的现象模型。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱:kefu@zhangqiaokeyan.com

京公网安备:11010802029741号 ICP备案号:京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有
  • 客服微信

  • 服务号