Theoretical study and physical tests of circular hole-edge stress concentration in long glass fiber reinforced polypropylene composite
Theoretical study and physical tests of circular hole-edge stress concentration in long glass fiber reinforced polypropylene composite
复制标题
长玻纤增强聚丙烯复合材料圆孔边缘应力集中的理论研究与物理试验
DOI：
10.1016/j.compstruct.2020.111884
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发表时间：
2020-03-15
影响因子：
6.3
通讯作者：
Han, Xu
中科院分区：
文献类型：
--
作者：
Duan, Shuyong;Zhang, Zhanming;Han, Xu
长玻璃纤维增强聚丙烯（LGFRP）复合材料具有力学性能高、设计灵活等优点，在汽车零部件中得到了广泛的应用。汽车结构件的机械连接中存在各种孔边应力集中问题。因此，本文的目的是研究LGFRP复合材料圆孔边缘的应力集中。本文首先建立了考虑切割面积和损伤因子的LGFRP复合材料孔边应力集中的理论模型，并考虑了孔尺寸效应。相应的物理测试进行拉伸载荷下的数字图像相关（DIC）系统的监测。实验结果表明，应力集中的影响范围在孔半径的4倍范围内。理论预测与实验结果吻合较好。应力集中系数（SCF）的计算表明，SCF增加的圆孔半径。研究结果为分析LGFRP复合材料孔边应力集中的力学性能奠定了基础，对合理设计LGFRP复合材料在汽车零部件中的应用具有重要意义。
The long glass fiber reinforced polypropylene (LGFRP) composite has been widely used in automotive components due to its remarkable advantages of high mechanical properties and flexible design features. Automotive structural components usually suffer various intrinsic hole-edge stress concentration in mechanical joints. Thus, the objective of this work is to investigate the circular hole-edge stress concentration of the LGFRP composite. A theoretical model, which is in view of cutting area and damage factor, is originally developed to predict the hole-edge stress concentration in LGFRP composite with regard to the hole size effect. Corresponding physical tests were conducted under tensile loading monitored by a digital image correlation (DIC) system. The experimental results reveal that the influenced area of the stress concentration is within the range of four times of the hole radius. The theoretical predictions are in good agreement with the experimental results. The stress concentration factor (SCF) is calculated to demonstrate that SCF increases with the increasing circular hole radius. The conclusions obtained from this work lay the basis on the mechanical performance of the LGFRP composite subject to hole-edge stress concentrations, and is of importance to rationalize appropriate design of the LGFRP composite in automotive components.