复合材料与被修航空铝合金结构件的性能匹配性研究

【作者】 梁重云；

【导师】 曾竟成；

【作者基本信息】 中国人民解放军国防科学技术大学 ， 材料学， 2002， 硕士

【摘要】 本文采用碳纤维、碳-玻混杂纤维复合材料作为增强体，环氧树脂E-44作为基体，分别按照单向、正交和准各向同性三种不同的铺层方式制成复合材料作为补片材料，采用胶接固化工艺修补中心带孔的航空铝合金板，修补前对航空铝合金构件表面采取了刷涂KH-560硅烷偶联剂、浸涂KH-560硅烷偶联剂、刷涂KH-560后刷涂SY-D9防腐底胶三种不同的腐蚀防护方案。 利用激光导热仪、拉伸试验机与高分辨电子显微镜等检测手段研究了复合材料补片与被修补航空铝合金结构件的热匹配性、力学性能匹配性；观察了补片-铝合金界面腐蚀形貌，定性分析了腐蚀产物与腐蚀机理。以有限元分析为基础，通过力学性能测试，探讨了不同类型的复合材料补片对中心开孔铝合金板的修复效果。 研究结果表明（1）采用碳-玻混杂纤维复合材料（准各向同性铺层）作为补片胶接修补中心开孔的铝合金构件是可行的，与碳纤维复合材料相比，热膨胀系数由1.01×10^-6K^-1提高到3.41×10^-6K^-1，与铝合金热膨胀系数相差最小。承载能力恢复到完好板的80％，能满足胶接修补的需要。（2）采用碳纤维／环氧树脂复合材料修补铝合金结构件，在大气环境下，对修补件进行挂片试验，通过SEM,TEM,HRTEM分析表征，结果表明：在铝合金表面，沿着纤维轴向发生了较为严重的点蚀和缝隙腐蚀，腐蚀产物为氧化铝。（3）在铝合金表面刷涂硅烷偶联剂KH-560和SY-D9底胶能有效抑制铝合金表面的腐蚀，并且将疲劳寿命由未采取防腐措施的的6400次提高到20000次。更多还原

【Abstract】 In this study, patch composite materials were fabricated through employing carbon fiber or carbon-glass fiber as reinforcement material and employing E-44 epoxy resin as matrix under three different plying models such as unidirection. orthotropic and quasi-isotropy. The aeronautic aluminium alloy components accompanyed with a inner hole were brushed coating or immersed coating with K.H-560 silane coupling agent, or SY-D9 adhesive followed by KH-560 to protect the metal surface from corrosion.Laser thermo-conductor, high resolution TEM were used to investigate the thermo or mechnical matching between composite patch and aluminium alloy components.The interface inside the fixing region were observed directly by SEM or TEM and thereby the corrosion mechanism was analyzed. Under finite element programme, via examining the mechanical property, the repairing effect from different types of composite patchs on the aluminium sheets with a center hole were also studied.It were shown that carbon mixed with glass fibers (under quasi-isotropy plying) used as patch to repair aluminium sheets with a center hole could meet the demond of bonding-repair.Compared with carbon fiber composite, the thermo-expansion coefficient was increased from 1.01×10-6K-1 to 3.41×10-6K-1, mostly approaching the thermo-expansion coefficient of aluminium alloy. It was found from the Cf/epoxy working at atmosphere examination, by SEM, TEM and HRTEM, that along axis dirction of the fiber dot corrision and aperture corrision cooured onside the skin of the aluminium sheet and the corrision product was aluminium oxide.Coating KH560 silane coupling agent and SY-D9 adhesive onside the aluminium skin could effectly control the corrsion and increase the fatigue life-span from 6400time to 20000 times.更多还原