Crashworthiness analysis of polymer composites under axial and oblique impact loading

A study was made to evaluate the design variables that affect the crashworthiness parameters of an energy absorber while dissipating the crash forces during road vehicle accidents. In order to find out causes, nonlinear crushing analysis is performed with the finite element code of ABAQUS/Explicit software. An investigation was conducted on homogeneous and heterogeneous ply orientation modeled structure of composite materials under axial and oblique impact loadings to find out the suitable model or structure for lightweight vehicle applications according to the crashworthiness. Crashworthiness parameters such as peak force and deformation length were considered, to investigate acomposite tube under axial and oblique loading conditions with materials such as carbon fiber reinforced plastic (CFRP), glass fiber reinforced plastic (GFRP). Continuum Damage Mechanics (CDM) approach is used to observe the changes and investigation on the dynamic response of composite material under sudden crashes in a different arrangement. A progressive damage model is adapted to determine the status of damage of elements in each failure with references to predefined energy absorption value. Hashin damage criteria are used, to estimate the reduction of stiffness of the material while crack initiation and its propagation during impacts. Different tube arrangement of fiber orientations (0 degrees, +/-45 degrees, 90 degrees) of ply and axial and oblique types of impact loading were mostly affecting results a lot in a crushing analysis. Non homogenous composite tube showed the better crashworthiness parameters than the homogenous structure. In oblique loading analysis, in both cases (CFRP and GFRP), the peak force and the deformation values decrease with increases in oblique angle due to the change of fiber properties, inclination as well as the contact area between the tube and impactor.