高温老化对玄武岩纤维增强树脂复合材料-铝合金单搭接接头失效的影响

Effect of high temperature exposure on adhesively bonded basalt fiber reinforced polymer composite-aluminum alloy single lap joints

  • 摘要: 为了研究持续高温环境对车用新材料粘接结构力学性能的影响,加工了铝合金-铝合金(Al-Al)和玄武岩纤维增强树脂复合材料-铝合金(BFRP-Al)单搭接接头,在高温(80℃)环境下进行了0天(未老化)、5天、10天、15天的老化实验,并对胶粘剂和BFRP复合材料进行了DSC和FTIR测试,分析高温老化后胶粘剂、BFRP复合材料的玻璃化转变温度(Tg)和化学成分变化,通过准静态拉伸测试获得老化后接头的失效载荷,并对其失效模式进行分析。研究结果表明:高温环境下,胶粘剂会发生后固化及氧化反应,BFRP复合材料发生热分解及氧化反应;Al-Al接头的失效载荷随老化周期的增加而不断增大,老化前后的失效模式均为内聚失效,其性能变化主要由胶粘剂决定;BFRP-Al接头的失效载荷先增加后减小,不同老化周期的接头均发生内聚和撕裂的混合失效,其性能变化由胶粘剂和BFRP复合材料共同作用决定,且随着老化周期的增加,BFRP复合材料撕裂面积不断增大,BFRP-Al接头的失效模式越来越倾向于玄武岩纤维/树脂界面的破坏,BFRP复合材料老化对接头失效载荷的影响越来越显著。

     

    Abstract: To investigate the degradation mechanism of new material adhesive structures applied to automobile after experiencing continuous high temperature environment, adhesively bonded aluminum alloy-aluminum alloy(Al-Al) and basalt fiber reinforced polymer composite-aluminum alloy(BFRP-Al) single lap joints were manufactured and then were exposed at 80℃ for 0 day, 5 days, 10 days, 15 days. DSC and FTIR were used to analyze the glass transition temperature (Tg) and chemical components changes of the adhesive and BFRP composite after high temperature exposure. The quasi-static state tensile tests were conducted to acquire the failure loads and the failure modes were also analyzed. The results show that the adhesive involves post-curing and oxidation reactions and the BFRP composite involves thermal decomposition and oxidation reactions under the continuous high temperature environment. The failure load of the Al-Al joints constantly increases and the failure mode is cohesive failure before and after aging which is determined by the adhesive. While the failure load of the BFRP-Al joints firstly increases and then decreases and the failure mode is mixed failure of cohesive and fiber tear with different aging time which is affected by the adhesive and BFRP composite together. With the increase of aging time, the area of the BFRP composite tear gets larger and the failure mode tends to be the basalt fiber/resin interface failure which shows that the effect of the degradation of BFRP composite is more and more significant.

     

/

返回文章
返回