Experimental study of tensile behavior of self-healing fiber-metal laminates composites with chopped hollow glass fibers

Fiber metal laminates (FMLs) are a family of hybrid composite structures formed from the combination of metal layers sandwiching a fiber- reinforced plastic layer. Because of low weight and better mechanical properties in comparison with aluminum alloys and other composites, they have found a wide range of use in aerospace industriy. In the case of deep micro-cracks within the FMLs, they must be replaced. To avoid of replacing the FMLs, the self-healing phenomenon is an appropriate strategy to control the defects and micro-cracks. In this research a series of chopped micro glass tubes were employed to provide a self-healing system. These chopped micro glass tubes were filled with epoxy resin hardener as a healing agent system. When the structure is exposed under loading condition, the created damages and micro-cracks rupture the chopped micro-glass tubes and the healing agent flows in the damage area and over a time span the defects will be healed and eliminated. The aim of this study is to find out the appropriate chopped micro-glass tubes volume fraction and the healing time to obtain an efficient healing. For this purpose, the chopped micro-tubes containing 4, 8, and 12 Vol.% were incorporated in epoxy- glass fibers composite and the tensile behavior observed for the specimens were assessed during different healing time. The highest healing efficiency of 58.3% was observed for the specimen with 8% healing agent.