三点弯曲工况下复合材料层合板的应力变化

Stress change of composite laminates in three point bending

为研究三点弯曲工况下复合材料层合板的应力问题,基于连续介质损伤力学以及Hashin失效准则,建立复合材料层合板三点弯曲有限元模型。模拟三点弯曲成形过程,讨论成形过程中应力分布及变化规律。结果表明:0°铺层应力值始终高于90°铺层,下表面的应力值小于上表面,但下表面的应力值达到最大值的时间要早于上表面;沿X轴方向,越接近压头位置,上下表面的应力差越小,在板料端部上下表面应力值相等;沿Y轴方向,上下表面的应力值变化幅度较小,上下表面的应力差基本保持不变。

To research the stress problem of composite laminates in three point bending,the finite element model was set up based on continuum damage mechanics and Hashin failure criterion.The three point bending process was simulated,and the main focus was put on the stress distribution and its change law during the forming process.The results indicate that the stresses of 0°plies are always greater than those of 90°plies.The stress on the bottom surface of the laminates is less than that on the top surface,but less time is spent when the stress on the bottom surface reaches maximum,compared with the top surface.In X direction,the stress difference between the top suface and the bottom surface decreases when approching the upper head,and the stress on the bottom surface is equal to that on the top surface at the side of the laminates.In Y direction,both the stress on the bottom surface and the stress on the top surface show little change,and the stress difference between the top suface and the bottom surface almost keeps constant.