树脂基复合材料动态力学性能及应变率效应研究

Study on Dynamic Mechanical Properties and Strain Rate Effect of Resin-Based Composites

基于一维应力波理论,采用分离式Hopkinson压杆和拉杆技术对铺层树脂基复合材料进行了中高应变率下的动态力学性能研究,获得了不同应变率下不同加载方向树脂基复合材料的应力应变曲线,并就应变率效应对材料失效模式和强度极限的影响进行了进一步研究。研究发现:树脂基复合材料的压缩强度表现为较为明显的正应变率效应,而压缩模量表现为负应变率效应;拉伸强度及拉伸模量几乎不受应变率影响;纬向方向拉伸强度高于压缩强度,经向方向拉伸强度低于压缩强度;纬向方向抗拉和抗压能力均高于经向方向;试样的失效模式均未表现出应变率相关性,且与加载方向无关。所采用的试样设计方法与测试方法可为复合材料动态力学性能的研究提供参考,得出的结论可为树脂基复合材料结构的设计与抗冲击的有效数值模拟提供支撑。

Based on the one-dimensional stress wave theory,the dynamic mechanical properties of laminated resin-based composites under medium and high strain rates are studied by using the separated Hopkinson compression bar and pull rod technology.The stress-strain curves of the resin-based composites under different strain rates and different loading directions are obtained,and the influences of the strain rate effect on material failure mode and strength limit are further studied.It is found that the compression strength of resin-based composites shows an obvious positive strain rate effect,while the compression module shows a negative strain rate effect.The tensile strength and the tensile modulus are almost unaffected by strain rate.The tensile strength in the latitude direction is higher than the compression strength,and the tensile strength in the longitude direction is lower than the compression strength.The tensile and compressive capacities in the latitude direction is higher than those in the longitude direction.The failure modes of the specimens do not show strain rate correlation and are independent of the loading direction.The sample design method and test method can provide reference for the study of dynamic mechanical properties of composites,and the conclusions can provide support for the design of resin-based composite structure and effective numerical simulation of impact resistance.