单向纤维增强SiCf/SiC复合材料单轴拉伸损伤失效机制  

Damage failure mechanism of unidirectional fiber reinforced SiCf/SiC composites under uniaxial tension

作　　者：刘波[1] 刘翠云 马朝利[3] LIU Bo;LIU Cuiyun;MA Chaoli(School of Aeronautic Science and Engineering,Beihang University,Beijing 100191,China;Research Institute of Frontier Science,Beihang University,Beijing 100191,China;School of Materials Science and Engineering,Beihang University,Beijing 100191,China)

机构地区：[1]北京航空航天大学航空科学与工程学院,北京100191 [2]北京航空航天大学前沿科学技术创新研究院,北京100191 [3]北京航空航天大学材料科学与工程学院,北京100191

出　　处：《复合材料学报》2022年第9期4483-4497,共15页Acta Materiae Compositae Sinica

基　　金：国家科技重大专项(J2019-VI-0001-0114)。

摘　　要：本文对纤维增强陶瓷基复合材料在单向载荷下的损伤失效机制进行了研究。根据常规的剪滞模型,引入库仑定律描述界面剪应力,根据能量平衡方法和断裂力学脱粘准则,计算了基体的稳态开裂应力和界面的脱粘长度。分析了不同剪滞模型下基体稳态开裂应力的区别和适用范围,讨论了界面剪应力、界面摩擦系数、界面脱粘能、纤维体积分数等对基体稳态开裂应力的影响。采用剪滞模型描述纤维增强陶瓷基复合材料在损伤后的细观结构应力场,根据基体裂纹随机演化方法确定基体裂纹的间距,根据断裂力学脱粘准则描述界面的脱粘行为,将剪滞模型和损伤模型结合预测了单向纤维增强陶瓷基复合材料在单轴载荷下的应力-应变曲线,讨论了各因素对应力-应变曲线的影响。This paper studied the damage failure mechanism of fiber-reinforced ceramic composites under unidirectional loading. According to the conventional shear-lag model, Coulomb’s law was introduced to describe the interfacial shear stress. According to the energy balance method and the debonding criterion of fracture mechanics,the steady-state cracking stress of the matrix and the debonding length of the interface were calculated. The difference and applicable range of the steady-state cracking stress of the matrix under different shear lag models were analyzed, and the effects of the interfacial shear stress, the interfacial friction coefficient, the interfacial debonding energy, and the fiber volume fraction on the steady-state cracking stress of the matrix were discussed. The shear lag model was used to describe the microstructure stress field of the fiber-reinforced ceramic composites after damage,the distance between the matrix cracks was determined according to the random evolution method of matrix cracks, and the debonding behavior of the interface was described according to the fracture mechanics debonding criterion. Combined with the damage model, the stress-strain curve of unidirectional fiber-reinforced ceramic composites under unidirectional load was predicted, and the influence of various factors on the stress-strain curve was discussed.

关 键 词：陶瓷基复合材料 连续纤维增强 剪滞模型 纤维脱粘 基体裂纹 

分 类 号：TB332[一般工业技术—材料科学与工程] V214.8[航空宇航科学与技术—航空宇航推进理论与工程] V414.8