PI纤维增强EPDM绝热层力学性能波动性拉伸损伤机制研究  

Investigation on mechanical properties unstable tensile damage mechanism of EPDM insulation reinforced by PI fiber

作　　者：刘琮佩璘 王明超[1] 张箭[1] 徐胜良[1] 黄志萍[1] LIU Congpeilin;WANG Mingchao;ZHANG Jian;XU Shengliang;HUANG Zhiping(Science and Technology on Aerospace Chemical Power Laboratory,Hubei Institute of Aerospace Chemical Technology,Xiangyang441003,China)

机构地区：[1]航天化学动力技术重点实验室,湖北航天化学技术研究所,襄阳441003

出　　处：《固体火箭技术》2022年第5期772-778,共7页Journal of Solid Rocket Technology

摘　　要：聚酰亚胺(PI)纤维由于良好阻燃性能,广泛应用于三元乙丙(EPDM)绝热层中。PI纤维增强的EPDM绝热层压延方向力学性能受纤维的含量、分散程度等因素影响,存在波动性。为揭示其波动机制,建立了包括样品前处理在内的测试、分析方法,利用微米三维立体显微镜(3D-CT)、扫描电子显微镜(SEM)配拉伸台的原位拉伸手段,对绝热层压延方向原位拉伸的不同阶段拉伸损伤过程进行了研究,对EPDM绝热层内部纤维分散情况以及拉伸过程的孔隙变化、裂纹变化、纤维与橡胶基体脱粘方式进行了分析。结果表明,绝热层在拉伸过程中的损伤破坏机制为由EPDM基体开始,随后在PI纤维/EPDM界面发生脱粘。由于PI纤维分散不均匀,导致绝热层压延方向力学性能波动。Polyimide(PI)fiber is widely used in EPDM insulation due to its good flame retardant properties.The mechanical properties of PI fiber-reinforced EPDM insulation in the rolling direction are unstable,which are affected by some factors:such as fi-ber content and dispersion degree.In order to reveal its fluctuation mechanism,a test and analysis method including sample pretreat-ment was established;combined with a tensile apparatus,the in-situ tensile damage process at different stages of the EPDM insula-tion in the rolling direction were studied by means of three-dimensional micron X-Ray computed tomography(3D-CT)and scanning electron microscope(SEM).The fibers dispersion in the EPDM insulation as well as pore changes,crack changes and debonding mode between fibers and rubber matrix during the stretching process were analyzed.The results reveal that the insulation damage re-sults from the EPDM matrix,and then debonding occur at the PI fiber/EPDM interface.Due to the uneven dispersion of PI fibers,the mechanical properties of the insulation in the rolling direction fluctuate.

关 键 词：EPDM绝热层 PI纤维 原位拉伸扫描 损伤机制 力学性能 波动性 

分 类 号：V255[一般工业技术—材料科学与工程]