Numerical Evaluation of Stiffness and Energy Absorption of a Hybrid Unidirectional/Random Glass Fiber Composite

作者：Yang Wensong; Pelegri Assimina A^*

来源：Journal of Engineering Materials and Technology-Transactions of the ASME, 2011, 133(4): 041018.

DOI：10.1115/1.4005253

• composite structure
• energy absorption
• finite element
• glass fiber
• impact
• stiffness

A finite element method is employed to numerically evaluate the stiffness and energy absorption properties of an architecturally hybrid composite material consisting of unidirectional and random glass fiber layers. An LS-DYNA finite element model of a composite hollow square tube is developed in which the position of the random fiber layers varies through the thickness. The assessment of the stiffness and energy absorption is performed via three-point impact and longitudinal crash tests at two speeds, 15.6 m/s (35 mph) and 29.0 m/s (65 mph), and five strain rates, (epsilon) over dot = 0.1 s(-1), 1 s(-1), 10 s(-1), 20 s(-1), and 40 s(-1). It is suggested that strategic positioning of the random fiber microstructural architecture into the hybrid composite increases its specific absorption energy and, therefore, enhances its crashworthiness. The simulation data indicate that the composite structure with outer layers of unidirectional lamina followed by random fiber layers is the stiffest due to the considerable superior specific energy absorption of the random fiber micro-architecture. Moreover, it is illustrated that the specific energy absorption increases with the increased ratio of impact contact area over cross-section area. Of all the parameters tested the thickness of the unidirectional laminate on the specific energy absorption does not appear to have a significant effect at the studied thickness ratios. [DOI: 10.1115/1.4005253]

• 出版日期2011-10