SiC/Ti-6Al-4V复合材料在横向拉伸载荷下界面失效行为的数值模拟  

Numerical simulation of the interface failure mechanism of SiC/Ti-6Al-4V composites under the transverse tensile stress

作　　者：原梅妮[1,2] 杨延清[2] 李茂华[2] 

机构地区：[1]中北大学机电工程学院,太原030051 [2]西北工业大学凝固技术国家重点实验室,西安710072

出　　处：《复合材料学报》2012年第6期159-163,共5页Acta Materiae Compositae Sinica

基　　金：教育部博士点新教师基金(20101420120006);凝固技术国家重点实验室博士后基金(BP201004);国家自然科学基金(50871086)

摘　　要：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 of SiC/Ti - 6Al - 4V composites and the transverse tensile test were simulated by finite element method. The cruciform specimen was selected to conduct the transverse tensile test of SiC/Ti - 6Al - 4V composites. In finite element analysis, the plain stress finite element model was used to analyze the interface stress distribution and failure mechanism of the cruciform specimen under the transverse tensile stress. The axisymmetric finite element model was adopted to analyze the interface debonding process and the effects of residual stress on the radial stress distribution at the interface. The results show that under the transverse tensile stress, the interface failure of the cruciform specimen is only resulted from the radial stress. The interface failure mode is the normal failure not the tangential failure. The interface debonding of the cruciform specimen appears in the middle of the interface. With the increasing of the transverse tensile stress, the interface debonding of the cruciform specimen symmetrically extends to both sides. Radial stresses at the interface increase with the decreasing thermal residual stresses.

关 键 词：SIC Ti-6Al-4V复合材料 界面 有限元分析 横向拉伸试验 残余应力 

分 类 号：TB331[一般工业技术—材料科学与工程]