Atomistic Study on the Tensile Properties of Hexagonal AlN, BN, GaN, InN and SiC Sheets

Molecular dynamics simulations were carried out to investigate the tensile mechanical behavior of hexagonal aluminum nitride (AlN), boron nitride (BN), gallium nitride (GaN), indium nitride (InN), and silicon carbide (SiC) monolayer sheets. The Tersoff and Tersoff-like potentials are used to model the interatomic interaction. Every sheet contains 4032 atoms. Stress-strain curves are established in the armchair and zigzag directions for uniaxial tensile response. Compared to graphene, hexagonal BN, SiC, AlN, InN, and GaN monolayer sheets exhibit approximately 77%, 53%, 41%, 27%, and 25% in Young's modulus; and 86%, 49%, 36%, 22% and 26% in fracture stress in the zigzag direction, respectively. Fracture strains appear about 19.5-22.8% and 15.5-17.7% in the zigzag and armchair directions, respectively. It is found that fracture stress-Young's modulus ratios of these 5 sheets and graphene are fairly different.