In this paper, a micromechanical constitutive model for prior exposure tensile damage and fracture of fiber-reinforced ceramic-matrix composites is developed considering the multiple damage mechanisms of matrix multicracking, interface debonding and oxidation, and fiber fracture. The relationships between prior exposure temperature, duration time, interface debonding fraction, broken fiber fraction, tensile strength, and fracture strain of C/SiC and SiC/SiC composites are established. The experimental prior exposure tensile damage evolution and final fracture of two-dimensional (2D) C/SiC and SiC/SiC composites are predicted for different temperatures and duration times. The comparison analysis of prior exposure composite tensile strength, fracture strain, interface debonding fraction, and broken fiber fraction between 2D C/SiC and SiC/SiC composites is investigated. The effects of constituent properties and temperature on prior exposure tensile damage and fracture of 2D C/SiC and SiC/SiC composites are discussed. For 2D C/SiC and SiC/SiC composites under prior exposure at 1300℃, the fracture strain decreased with fiber volume, interface shear stress, and prior exposure temperature, and increased with fiber characteristic strength; the tensile strength increased with fiber volume and fiber characteristic strength, and decreased with prior exposure temperature; the interface debonding fraction decreased with fiber volume, and increased with prior exposure temperature; and the fiber broken fraction decreased with fiber volume and fiber characteristic strength, and increased with prior exposure temperature.

中文翻译：

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二维碳/碳化硅和碳化硅/碳化硅纤维增强陶瓷基复合材料先前暴露拉伸损伤和断裂的比较

在本文中，考虑到基体多裂纹、界面脱粘和氧化以及纤维断裂的多种损伤机制，建立了纤维增强陶瓷基复合材料的先验拉伸损伤和断裂的微机械本构模型。建立了 C/SiC 和 SiC/SiC 复合材料的预先暴露温度、持续时间、界面脱粘率、断裂纤维率、拉伸强度和断裂应变之间的关系。预测了二维 (2D) C/SiC 和 SiC/SiC 复合材料在不同温度和持续时间下的实验性先前暴露拉伸损伤演变和最终断裂。暴露前复合材料拉伸强度、断裂应变、界面脱粘率的对比分析，研究了 2D C/SiC 和 SiC/SiC 复合材料之间的断裂纤维分数。讨论了成分特性和温度对 2D C/SiC 和 SiC/SiC 复合材料的预先暴露拉伸损伤和断裂的影响。2D C/SiC和SiC/SiC复合材料在1300℃预暴露条件下，断裂应变随纤维体积、界面剪切应力和预暴露温度的增加而减小，随纤维特征强度的增加而增加；拉伸强度随着纤维体积和纤维特征强度的增加而增加，随着暴露前温度的增加而降低；界面脱粘率随着纤维体积的增加而降低，随着暴露温度的升高而增加；纤维断裂率随着纤维体积和纤维特征强度的增加而降低，随着暴露前温度的升高而增加。讨论了成分特性和温度对 2D C/SiC 和 SiC/SiC 复合材料的预先暴露拉伸损伤和断裂的影响。2D C/SiC和SiC/SiC复合材料在1300℃预暴露条件下，断裂应变随纤维体积、界面剪切应力和预暴露温度的增加而减小，随纤维特征强度的增加而增加；拉伸强度随着纤维体积和纤维特征强度的增加而增加，随着暴露前温度的增加而降低；界面脱粘率随着纤维体积的增加而降低，随着暴露温度的升高而增加；纤维断裂率随着纤维体积和纤维特征强度的增加而降低，随着暴露前温度的升高而增加。讨论了成分特性和温度对 2D C/SiC 和 SiC/SiC 复合材料的预先暴露拉伸损伤和断裂的影响。2D C/SiC和SiC/SiC复合材料在1300℃预暴露条件下，断裂应变随纤维体积、界面剪切应力和预暴露温度的增加而减小，随纤维特征强度的增加而增加；拉伸强度随着纤维体积和纤维特征强度的增加而增加，随着暴露前温度的增加而降低；界面剥离率随着纤维体积的增加而降低，随着暴露前温度的增加而增加；纤维断裂率随着纤维体积和纤维特征强度的增加而降低，随着暴露前温度的升高而增加。