Energy absorption capability of composite hexagonal ring systems

• Published in: Materials in engineering 2012-02, Vol.34, p.201-210
• Main Authors: Mahdi, E., Hamouda, A.M.S.
• Format: Article
• Language: English
• Subjects: Angles (geometry); Brittle fracture; Buckling; Composite; Crushing; Design engineering; Energy absorption; Glass; Glass fiber reinforced plastics; Mandrels; Platens
• ISSN: 0261-3069
• DOI: 10.1016/j.matdes.2011.07.070

An extensive experimental investigation of inplane crushing of composite hexagonal ring system between platens has been carried out. Woven roving glass/epoxy hexagonal ring system with different angles and arrangement were employed. The rings angles are varying between 45° and 70°. The wet winding process was used to fabricate the woven E-glass fabric/epoxy specimens. Six layers of woven E-glass fabric/epoxy wrapped over wooden mandrel to get thickness of about 3 mm. The composite hexagonal tubes were then cured at room temperature (32 °C) for 24 h to provide optimum hardness and shrinkage. Repeatability of the results was ensuring by performing the experiments on three identical specimens. [Display omitted] ► As the hexagonal angle increases, ring systems load carrying capacity increases. ► Arrangement is significantly influenced the behavior of hexagonal ring system. ► There are three main failure mechanisms predicted to describe the systems behavior. ► Microscopic investigation has been carried out to explain the failure mechanism. An extensive experimental investigation of inplane crushing of composite hexagonal ring system between platens has been carried out. Woven roving glass/epoxy hexagonal ring system with different angles and arrangement were employed. The rings angles are varying between 45° and 70°. Six layers of woven roving E-glass fabric/epoxy wrapped over wooden mandrel to get thickness of about 3 mm. Typical histories of their crushing mechanism are presented. Behavior of ring as regards the initial crushing load, post crushing load, energy absorbed and mode of crushing has been presented and discussed. Results showed that the crush failure loads and energy absorption capability are greatly affected by the ring geometry, arrangement and loading conditions. As the ring angle increases the energy absorption capability increases and consequently, composite hexagonal ring with 70° exhibited the highest energy absorption capability among tested specimens. It is also found that energy absorption capability for systems crushed in-plane X2 higher than X1.