水分-载荷耦合作用下2D编织复合材料的力学行为  

Mechanical behavior of 2D braided composites under the coupling effect of moisture and load

作　　者：成朝辉 刘斌[1] 向栋 徐绯[1] 冯威[1] CHENG Zhaohui;LIU Bin;XIANG Dong;XU Fei;FENG Wei(School of Aeronautics,Northwestern Polytechnical University,Xi'an 710072,China;Chongqing Hongyu Precision Industry Group CO.,LTD.,Chongqing 402760,China)

机构地区：[1]西北工业大学航空学院,西安710072 [2]重庆红宇精密工业集团有限公司,重庆402760

出　　处：《复合材料学报》2024年第10期5283-5293,共11页Acta Materiae Compositae Sinica

基　　金：国家自然科学基金(12272320);国家自然基金青年项目(12202336);中央高校基本科研业务费专项资金(D5000230141)。

摘　　要：为了研究长期水分-载荷耦合作用下2D编织复合材料的吸湿行为及性能劣化规律,设计了水分-载荷耦合环境老化装置,开展了不同应力水平下碳纤维增强环氧树脂(T300/H69)平纹编织复合材料的吸湿试验及吸湿后的拉伸试验。结果表明:T300/H69编织复合材料的吸湿量与拉伸预应力总体上呈现正相关,随着拉伸预应力的增大而增大;相对于水分单独作用,水分-载荷耦合作用下材料的弹性模量和强度退化更明显,在140%σ_(s)(σ_(s)为屈服强度)预应力下作用432 h后,编织复合材料的弹性模量及失效强度分别下降达55.9%和35.4%。此外,通过宏微观断面分析,进一步揭示长期水分-载荷耦合作用下编织复合材料性能的退化机制,并基于Shiva剩余强度理论,改进了水分-载荷作用下复合材料的剩余强度模型,预测结果良好,为复杂环境下复合材料耐久性设计提供指导。In order to study the moisture absorption behavior and performance degradation law of 2D braided composites under long-term moisture-load coupling,a moisture-load coupled aging device was designed.The moisture absorption test and tensile test after moisture absorption of carbon fiber reinforced epoxy resin(T300/H69)plain woven composite material under different stress levels were carried out.The results show that the moisture absorption of T300/H69 braided composites is positively correlated with the tensile prestress,and increases with the increase of tensile prestress.Compared with the effect of water alone,the elastic modulus and strength degradation of the material under moisture-load coupling are more obvious.After 432 h at 140%σ_(s)(σ_(s)is yield stress)prestress,the elastic modulus and failure strength of the braided composites decreased by 55.9%and 35.4%,respectively.In addition,the degradation mechanism of braided composites under long-term moisture-load coupling is further revealed by macro and micro section analysis.Based on Shiva's residual strength theory,the residual strength model of composites under moisture-load is improved,and the prediction results are good,which provides guidance for the durability design of composites in complex environment.

关 键 词：水分-载荷耦合 2D编织复合材料 吸湿 剩余强度 失效机制 

分 类 号：TB332[一般工业技术—材料科学与工程]