双向载荷下双轴向经编柔性复合材料有限元模拟

Finite element simulation of biaxial warp knitted flexible composite under biaxial loads

为更好地了解双向载荷下双轴向经编柔性复合材料拉伸和开缝撕裂性能,为材料性能评价及预测提供理论参考,利用有限元方法对材料拉伸和开缝撕裂的应力与应变曲线进行模拟,特别对3种不同加载比率下双向拉伸和双向载荷下开缝撕裂的应力与应变曲线进行模拟。结果表明:有限元模拟的双轴向拉伸及开缝撕裂的应力与应变曲线与试验结果在弹性阶段的拟合精度很好,但材料屈服后拟合值偏大;不仅可以模拟1∶1加载比率下材料的应力与应变曲线,而且可以模拟目前试验无法完成的其他任意载荷比下的应力与应变曲线。

To better understand the tensile and crack tearing properties of biaxial warp knitted flexible composite under biaxial loads and provide theoretical reference for evaluation and prediction of the properties of composite materials,this paper used finite element analysis to simulate the stress-strain curves for tensile and crack tearing tests of biaxial warp knitted fabrics flexible composite under biaxial loads,in particular,the simulation of the stress-strain curves for tensile and crack tearing tests under three different loading ratios.The results show that the simulated stress-strain curves based on finite element are fitted very well to the experimental values at the elastic phase,but fitting deviation is too large after yield point of the material.Theoretical results show that not only the stress-strain curve for tensile and crack tearing of biaxial warp knitted flexible composite under 1：1 load ratios can be simulated but also that under other arbitrary load ratios which can not be tested now can be simulated.