T300/AG80复合材料U形结构件成型残余应力的有限元模拟

Finite Element Simulation of Molding Residual Stress of T300/AG80 Composite U-shaped Structure Part

利用ABAQUS有限元软件建立T300碳纤维增强AG80环氧树脂(T300/AG80)复合材料U形薄壁结构件模型,研究了热压固化成型过程中的应力和回弹变形量(同步模拟脱模)变化以及脱模后的残余应力分布,通过小孔试验法对残余应力模拟结果进行了验证。结果表明:成型过程中,U形结构件侧壁和底面的应力和回弹变形量均随时间延长而增加;随着距底面距离或距对称中心距离的增大,应力和回弹变形量增大;脱模后,U形结构件对称中心处的残余应力最小,残余应力随着距底面距离或距对称中心距离的增大而增大;脱模前后释放的残余应力越大,回弹变形量越大;小孔法测得的残余应力与模拟结果的相对误差小于10%,说明模拟结果较准确。

A u-shaped thin-walled structure part model of T300 carbon fiber reinforced AG80 epoxy resin(T300/AG80)composite was established by ABAQUS finite element software.The stress and springback amount(synchronous demolding by simulation)changes during hot-press curing molding and the residual stress distribution after demolding were studied.The simulation of residual stress was verified by the small-hole test method.The results show that during the molding process,the stress and springback amount of the side wall and bottom surface of the U-shaped structure part increased with time.The stress and springback amount increased with the distance from the bottom surface or the distance from the center of symmetry.After demolding,the residual stress at the center of symmetry of the U-shaped structure part was the smallest,and the residual stress increased with the distance from the bottom surface or the distance from the center of symmetry.The greater the residual stress released before and after demolding,the greater the springback amount.The relative error between the residual stress measured by the small-hole method and the simulation was less than 10%,indicating the simulation was accurate.