Speaker
Description
Transition metal nitrides (TMNs) are vital protective coatings for structural and moving components due to their exceptional thermal stability, corrosion resistance, and mechanical properties. However, their strong covalent/ionic bonding and limited slip systems often lead to brittle fracture. Recent studies suggest that defect engineering—specifically via vacancies—is a promising strategy to achieve a synergy of strength and toughness. Despite this potential, the specific influence of different metal species and vacancy configurations on the mechanical response remains poorly understood. In this work, we systematically investigate IIIB-VIB group binary nitrides by introducing 10% and 20% concentrations of nitrogen and metal sub-lattice vacancies. Utilizing the high-fidelity GRACE universal potential, we performed shear simulations to compare strain behaviors and structural responses at 0K and 300K. Our results elucidate how metal species and vacancy configurations dictate the shear strength, deformation pathways, and maximum strain capacity of TMNs. This study clarifies the mechanisms of vacancy-driven strengthening and toughening, providing a theoretical foundation for the targeted design of high-performance ceramics.