论文部分内容阅读
采用有限元模拟了SiC/Ti-6Al-4V复合材料冷却过程和横向拉伸试验过程,横向拉伸试样采用十字形试样。分别建立了平面应力和轴对称有限元模型,采用平面应力有限元模型计算环绕纤维圆周的界面微区应力分布,预测界面失效机制。采用轴对称有限元模型分析复合材料界面脱粘过程以及残余应力对界面径向应力分布的影响。结果表明:对于SiC/Ti-6Al-4V复合材料十字形试样,在横向拉伸载荷下的界面失效由径向应力导致,界面失效模式为法向失效,剪切失效模式未发生;十字形试样在横向拉伸载荷下界面初始脱粘位置处于界面中间;随横向拉伸应力增加,十字形试样的界面脱粘对称向两边扩展;界面径向应力随残余应力降低而升高。
The cooling process and transverse tensile test of SiC / Ti-6Al-4V composite were simulated by finite element method. The cross-shaped specimens were cross-shaped specimens. The plane stress and the axisymmetric finite element model are respectively established. The plane stress finite element model is used to calculate the interface micro-stress distribution around the fiber circumference, and the interface failure mechanism is predicted. The axial symmetry finite element model was used to analyze the debonding process and the effect of residual stress on the radial stress distribution in the interface. The results show that the interfacial failure under transverse tensile load is caused by the radial stress and the failure mode of the interface is normal failure and the shear failure mode does not occur for the cruciform specimen of SiC / Ti-6Al-4V composite. Under the transverse tensile load, the initial debonding position of the interface is in the middle of the interface. With the increase of transverse tensile stress, the debonded interface of the cross-shaped sample expands symmetrically to both sides. The radial stress of the interface increases with the decrease of residual stress.