Multilayer graphene is an exceptional anisotropic material due to its layered structure composed of two-dimensional carbon lattices. Although the intrinsic mechanical properties of graphene have been investigated at quasi-static conditions, its behavior under extreme dynamic conditions has not yet been studied. We report the high–strain-rate behavior of multilayer graphene over a range of thicknesses from 10 to 100 nanometers by using miniaturized ballistic tests. Tensile stretching of the membrane into a cone shape is followed by initiation of radial cracks that approximately follow crystallographic directions and extend outward well beyond the impact area. The specific penetration energy for multilayer graphene is ~10 times more than literature values for macroscopic steel sheets at 600 meters per second.

Dynamic mechanical behavior of multilayer graphene via supersonic projectile penetration

Bending behavior of sandwich composite structures with tunable 3D-printed core materials

Innovative honeycomb-based structures have been paid substantial attention in recent years due to their superb mechanical performances and specific functions. The presented study made acomprehensive overview on the development of the innovative honeycomb-based structures in the past two decades, including filled-type, embedded, tandem, hierarchical, auxetics with Negative Poisson's Ratio (NPR), etc. Mechanical performances of these structures were commented with advantages and disadvantages, related on their geometric configurations, mechanical performance and dynamic response, respectively. The challenges as well as future directions were also analyzed. The achievements provide significant guidelines in designing of new generation light-weight honeycomb-based structures.

Recent advances in novel metallic honeycomb structure

Experimental and numerical study on the low-velocity impact behavior of foam-core sandwich panels

Ballistic impact mechanisms – A review on textiles and fibre-reinforced composites impact responses

http://portal.uc3m.es/portal/page/portal/dpto_mec_med_cont_teor_est/personal/carlos_santiuste/299.pdf

Modelling of composite sandwich structures with honeycomb core subjected to high-velocity impact

Residual flexural strength after low-velocity impact in glass/polyester composite beams

This study focuses on the analysis of influence of temperature and bolt torque on aeronautical joint behavior. A single-lap joint, according to ASTM D5961, with a titanium bolt and composite plates was considered. A numerical model based on FEM was developed to evaluate the stress in both bolt and composite plates. Load—displacement curves, stress fields, and induced damage showed, significantly, the influence of temperature combined with torque level on the joint. It was found that in the plate, both maximum and minimum levels of torque considered produced damage above critical threshold. This fact should be accounted for, during the design process of the joint.

/pdf/computational-analysis-of-temperature-effect-in-composite-al85vwsxqa.pdf

Enrique Barbero

Papers

Modelling of composite sandwich structures with honeycomb core subjected to high-velocity impact

Residual flexural strength after low-velocity impact in glass/polyester composite beams

Computational analysis of temperature effect in composite bolted joints for aeronautical applications

Dynamic crushing behaviour of agglomerated cork

Experimental analysis of perforation of glass/polyester structures subjected to high-velocity impact