基于局部均匀化多尺度方法的机织复合材料单轴拉伸力学行为研究

Study on Uniaxial Tensile Mechanical Behavior of Woven Composites Based on Local Homogenization Multi-Scale Method

机织碳纤维增强树脂基复合材料在厚度方向存在纤维的相互交织,拥有较复杂的纤维空间结构,因此具有优异的比刚度和比强度。本文建立了平纹机织复合材料的“微观-介观-宏观”的多尺度有限元渐进损伤模型,并对介观模型中的各成分进行具有等效性能的局部均匀化简化。基于微观力学失效理论判断纤维/基体损伤起始,通过ABAQUS有限元分析平台,开发用户自定义的子程序VUMAT,对平纹机织复合材料进行拉伸力学行为和损伤机理分析。结果表明:在拉伸载荷模拟中纤维束树脂损伤最为严重,纤维失效发生在经向纤维束中,且外层损伤相较于内层更加严重。试验和数值分析的结果误差均在2%以内,表明多尺度渐进损伤模型的可靠性。

The woven carbon fiber reinforced resin matrix composites have excellent specific stiffness and strength due to the interweaving of fibers in the thickness direction and the complex spatial structure of fibers.A multi-scale(microscopic,mesoscopic and macroscopic)finite element progressive damage model of woven carbon fiber reinforced resin matrix composites was established,and the components of the mesoscopic model were simplified by local homogenization with equivalent performance.The damage initiation of fiber/matrix was judged based on the micromechanical failure theory,and a user-defined subroutine VUMAT was developed to analyze the tensile mechanical behavior and damage mechanism of plain woven composites on the ABAQUS finite element analysis platform.The results show that the resin damage of the fiber yarns is the most serious in the tensile load simulation,and the fiber failure occurs in the warp fiber yarns,and the damage of the outer layer is more serious than that of the inner layer.The error of experimental and numerical analysis results is less than 2%,which indicates the reliability of the multi-scale progressive damage model.