论文部分内容阅读
使用有限元生成软件FEPG和表征热塑性复合材料AS4/PEEK非线性行为和应变率相关行为的三维粘塑性模型,计算了复合材料角铺设层合板在单向拉伸时的界面层间应力.层间应力的三维分布图表明,AS4/PEEK对称角铺设层合板的层间剪应力在自由边缘处存在很明显的自由边缘效应;层间正应力也存在自由边缘效应,对于轴向拉伸,其在自由边缘处的值为负.随着铺设角的增大,自由边缘处二者的值均减小.层间应力存在端头效应,甚至比边缘效应还明显.随着铺设角的增大,层间应力在两端头处的值降低,层间正应力由压应力变为拉应力.主要由纤维控制的角铺设AS4/PEEK层合板,在自由边缘处较大的层间剪应力是引起其层间分层的主要原因;主要由基体控制的角铺设AS4/PEEK层合板,其首先产生的是面内应力破坏,而不是层间分层.
The three-dimensional viscoplasticity model of FEPG, which characterizes the nonlinear behavior and strain rate behavior of the thermoplastic composites AS4 / PEEK, was used to calculate the interfacial interlaminar stresses of the composite angle-laying laminate under uniaxial tension. The three-dimensional distribution of stress shows that the interlaminar shear stress of the AS4 / PEEK symmetrical diagonal laminated plywood has a significant free edge effect at the free edge. There is also a free edge effect of the inter-layer normal stress. For the axial stretching, The value of the free edge is negative.With the increase of the laying angle, the value of the free edge decreases.The interlaminar stress has the effect of tip even more obvious than the edge effect.As the laying angle increases, The value of interlaminar stress decreases at both ends and the interlaminar normal stress changes from compressive to tensile stress.The AS4 / PEEK laminate, which is mainly composed of fiber-controlled corners, has a larger interlaminar shear stress at the free edge The main reason for its delamination is that AS4 / PEEK laminates, which are mainly controlled by the substrate, lay out the first in-plane stress failure instead of delamination.