Aluminum nanocomposites reinforced with monolayer polyaniline (C3N): assessing the mechanical and ballistic properties

Dynamic penetration behaviors of single/multi-layer graphene using nanoprojectile under hypervelocity impact

Single/multilayer graphene holds great promise in withstanding impact/penetration as ideal protective material. In this work, dynamic penetration behaviors of graphene has been explored using molecular dynamics simulations. The crashworthiness performance of graphene is contingent upon the number of layers and impact velocity. The variables including residual velocity and kinetic energy loss under different layers or different impact velocities have been monitored during the hypervelocity impact. Results show that there exists deviation from the continuum Recht–Ipson and Rosenberg–Dekel models, but these models tend to hold to reasonably predict the ballistic limit velocity of graphene with increasing layers. Besides, fractal theory has been introduced here and proven valid to quantitatively describe the fracture morphology. Furthermore, Forrestal–Warren rigid body model II still can well estimate the depth of penetration of multilayer graphene under a certain range of velocity impact. Finally, one modified model has been proposed to correlate the specific penetration energy with the number of layer and impact velocity.

Crack pathway analysis in graphene-like BC3 nanosheets: Towards a deeper understanding

Carbon based two-dimensional (2D) nanostructures have exceptional mechanical properties. Analysis of crack pathway in 2D graphenic materials allows for developing crack arrestors. Herein, we serve Molecular Dynamics (MD) to simulate the fracture behavior of 2D graphene-like boron-carbide (BC₃) by manipulating the crack length (10, 20, 30, 40, and 50 Å) and the crack arrestor (circular and square). Young's modulus, the failure stress, failure strain, and fracture toughness of theoretically born BC₃ nanosheets were then captured. The crack arrestors were studied in three different states (constant position, as well as 4 and 6 Å from crack tips). Three factors, i.e. the stress, crack length, and geometry of nanosheets determined crack pathway considering zigzag and armchair directions. Overall, circular arrestors more severely affected the fracture toughness, failure stress and failure strain with respect to square ones; while Young's modulus variation followed an inverse trend. Moreover, the highest Young's modulus was detected for cracks having length of 10 Å. Fracture toughness increased upon increasing the crack length. In conclusion, the crack arrestors were promising for tuning the mechanical properties of 2D nanosheets.