航空学报 > 2026, Vol. 47 Issue (2): 232093-232093   doi: 10.7527/S1000-6893.2025.32093

陶瓷基复合材料韧-脆性转变统计强度模型

杨成鹏1(), 贾斐2, 魏景超3   

  1. 1.西北工业大学 力学与交通运载工程学院,西安 710072
    2.西安电子科技大学 机电工程学院,西安 710071
    3.中国飞机强度研究所 强度与结构完整性全国重点实验室,西安 710065
  • 收稿日期:2025-04-07 修回日期:2025-07-06 接受日期:2025-07-10 出版日期:2025-07-16 发布日期:2025-07-15
  • 通讯作者: 杨成鹏 E-mail:yang@mail.nwpu.edu.cn
  • 基金资助:
    国家自然科学基金(12472142);国家自然科学基金(12072274);陕西省自然科学基金(2024JC-YBMS-308)

Statistical strength model for ceramic matrix composites in tough-to-brittle transition

Chengpeng YANG1(), Fei JIA2, Jingchao WEI3   

  1. 1.School of Mechanics and Transportation Engineering,Northwestern Polytechnical University,Xi’an 710072,China
    2.School of Mechano-Electronic Engineering,Xidian University,Xi’an 710071,China
    3.National Key Laboratory of Strength and Structural Integrity,Aircraft Strength Research Institute of China,Xi’an 710065,China
  • Received:2025-04-07 Revised:2025-07-06 Accepted:2025-07-10 Online:2025-07-16 Published:2025-07-15
  • Contact: Chengpeng YANG E-mail:yang@mail.nwpu.edu.cn
  • Supported by:
    National Natural Science Foundation of China(12472142);Natural Science Foundation of Shaanxi Province(2024JC-YBMS-308)

摘要:

连续纤维增强复合材料通常存在韧-脆性转变问题,其对复合材料的界面设计和整体性能评价具有重要意义。基于纤维应力场的弹性力学解答,应用剪滞理论和纤维随机断裂概率的统计分析方法,考虑纤维表面的应力集中效应,在单裂纹和多裂纹两种失效模式下,分别建立连续纤维增强陶瓷基复合材料(CMCs)的韧-脆性转变拉伸强度模型。针对2D-C/SiC复合材料的分析计算结果表明:拉伸强度对界面滑移应力敏感,随着界面滑移应力的增大,纤维应力集中效应增强,拉伸强度预测值先升高后降低;单裂纹模式下的拉伸强度预测值显著高于多裂纹模式,但两种模式下拉伸强度随界面滑移应力的变化规律相似;单裂纹模式下考虑纤维断裂拔出应力对CMCs整体承载能力的贡献时,模型预测的拉伸强度值显著提高,且随着拔出系数的增大拉伸强度持续增大。建立的模型强度预测值与文献中的试验数据吻合较好,证明了模型的合理性与准确性。

关键词: 陶瓷基复合材料, 统计强度模型, 界面脱黏, 基体开裂, 拉伸强度

Abstract:

Continuous fiber-reinforced composites usually present the problem of tough-to-brittle transition, which is of great significance for the interface design and overall performance evaluation of composites. Based on the elastic-mechanics solution of the fiber stress field, the shear-lag theory and the statistical analysis method of fiber random fracture probability, and meanwhile considering the stress concentration effect on fiber surface, a statistical tensile strength model for tough-to-brittle transition of continuous fiber-reinforced Ceramic Matrix Composites (CMCs) was established under two failure modes, namely single-crack mode and multi-crack mode. The analysis and calculation results with 2D-C/SiC composites show that the tensile strength is sensitive to the interfacial slip resistance; with the increase of interfacial slip stress, the fiber stress concentration effect is enhanced and the predicted value of the tensile strength firstly rises and then decreases. In comparison, the predicted tensile strength under the single-crack mode is significantly higher than that under the multi-crack mode, but the variation trend of the prediction with the interfacial slip stress is similar in the two modes. Under the single-crack mode, when considering the contribution of broken-fiber pullout stress to the overall load carrying capacity of CMCs, the model predicted tensile strength value is significantly higher, and the tensile strength continues to increase with the increase of the pullout coefficient. It is shown that the strength predictions of the developed model by this work are in good agreement with the experimental data in the literature, which demonstrates the rationality and accuracy of the theoretical model.

Key words: ceramic matrix composites, statistical strength model, interface debonding, matrix cracking, tensile strength

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