玻璃纤维增强聚碳酸酯复合材料的动态拉伸力学行为特征及其失效机理  

Dynamic Tensile Properties and Failure Mechanism of Glass Fiber Reinforced Polycarbonate Composite

作　　者：管海陆 张晓琼 舒洪基 王志华 GUAN Hailu;ZHANG Xiaoqiong;SHU Hongji;WANG Zhihua(College of Mechanical and Vehicle Engineering,Taiyuan University of Technology,Taiyuan 030024,Shanxi,China)

机构地区：[1]太原理工大学机械与运载工程学院,山西太原030024

出　　处：《高压物理学报》2023年第4期44-52,共9页Chinese Journal of High Pressure Physics

基　　金：山西省科技重大专项(202101120401008);山西省基础研究计划(20210302124691)。

摘　　要：为了探明由不同方向玻璃纤维增强的聚碳酸酯(polycarbonate,PC)复合材料在宽应变率范围内的拉伸力学行为特征及其失效机理,使用材料实验机、中应变率实验机和分离式Hopkinson杆实验装置,对玻璃纤维质量分数为20%、纤维方向不同(0°、45°及90°)的PC复合材料开展了0.001~1 000 s^(-1)应变率范围内的拉伸实验研究,并通过扫描电镜对加载后的3种试件断口进行了微观分析。实验结果显示,当加载应变率由0.001 s^(-1)增加至1 000 s^(-1)时,玻璃纤维方向为0°、45°和90°的3种试件的拉伸强度分别增加57.5%、58.2%和49.4%,破坏应变分别增加74.1%、125.1%和129.1%,说明玻璃纤维增强PC复合材料具有显著的应变率效应。玻璃纤维方向为0°的试件的拉伸强度高于其他两种试件,而其破坏应变低于其他两种试件。在应变率为0.001 s^(-1)的准静态加载下,玻璃纤维增强PC复合材料呈现出纤维拔出、纤维断裂、基体脆性断裂以及纤维与基体脱粘4种失效模式;在1 000 s^(-1)的高应变率加载下,玻璃纤维增强PC复合材料呈现出纤维拔出、纤维断裂、基体塑性变形、基体塑性断裂以及纤维与基体脱粘5种失效模式。高应变率加载下,玻璃纤维增强PC复合材料的破坏强度和破坏应变相较于准静态加载下大幅增加的主要原因是:绝热温升效应导致玻璃纤维增强PC复合材料内的PC基体软化,PC复合材料产生塑性变形,基体/纤维界面黏附力增强。In order to investigate the tensile mechanical behavior and failure mechanism of polycarbonate(PC)composite reinforced by short glass fibers in different orientations at a wide range of strain rates,the tensile experiments of PC composites with 20%glass fiber content and fiber orientations of 0°,45°and 90°were carried out at a strain rate range of 0.001-1000 s^(-1) by using a material test machine,a medium strain rate test machine,and a split Hopkinson tensile bar device.The fractured surface morphologies of the three types of specimens under the stain rate range of 0.001-1000 s^(-1) were analyzed with scanning electron microscopy.The experimental results showed that PC composites have significant strain rate effects on tensile propertie and failure mechanism.When the loading strain rate increases from 0.001 s^(-1) to 1000 s^(-1),the tensile strengths of the specimens contained 0°,45°and 90°glass fibers are increased by 57.5%,58.2%and 49.4%,respectively,while the failure strains are increased by 74.1%,125.1%and 129.1%,respectively.The tensile strength of specimen with glass fiber orientation of 0°is higher than that of the other two types of specimen,while the failure strain is lower than that of the other two types of specimen.Under the strain rate of 0.001 s^(-1) in quasi-static loading,there are four failure modes of the glass fiber reinforced PC composites:fiber pull-out,fiber fracture,matrix brittle fracture and fiber/matrix debonding.At the high strain rate of 1000 s^(-1),there are five failure modes:fiber pull-out,fiber fracture,matrix plastic deformation,matrix plastic fracture,and fiber/matrix debonding.The adiabatic temperature rise effect under high strain rate loading leads to a softening of the PC matrix in the glass fiber reinforced PC composite,resulting in a plastic deformation and an increase of matrix/fiber interface adhesion force,which is the main mechanism of the significant increase of the failure strength and failure strain compared with that under quasi-static loading.

关 键 词：聚碳酸酯 玻璃纤维 纤维方向 拉伸力学行为 应变率 失效机理 

分 类 号：O341[理学—固体力学] TB332[理学—力学]