局域外热源下层合材料烧蚀特性研究

Experimental Research on The Ablation of Lamination Composite Films

层合式柔性复合材料其强度、耐候性、密封性突出,在航空航天领域具有重要的应用价值。研究采用激光辐照的方法产生局域外热流,针对不同热流密度和氧气分压,对耐候层和高强度纤维层合材料的烧蚀特性进行了实验研究。实验结果表明,在局域外热源条件下,表面耐候层以热缩合破裂的形式与底层纤维脱开,从而使纤维材料暴露在外热源下,最终以纤维的受热分解和碳化实现材料的整体破坏。随着热流密度的增加,破坏过程明显加快,环境氛围对纤维的高温段烧蚀过程影响很大,而对耐候层的烧蚀过程几乎不产生影响。

Flexible lamination composite films with perfect performance on specific strength,weathering resistance,and sealing,are universal utilized in aerospace field. Continuous wave laser is used in this article to produce local external heat source,and the ablation characteristics of Tedlar foil/high strength fibers （Vectran/kevlar） lamination composite are studied under different atmosphere. The results show that Tedlar foil will shrink,break and boil off the fiber weaves,and then fiber weaves are exposed to external heat source. As the temperature rise up,fibers will decompose and carbonize,in the end the composite is destroyed. Heat flux density has positive effect on decreasing destroy time,and oxygen atmosphere operates when temperature is more than 500℃,and has little effect on tedlar ablation.