Mechanical Properties of Ti_(1-x-y)Al_xSi_yN Nanocomposite Studied by ab Initio

摘要

Using first principles calculations based on the density functional theory, we have studied the structural and mechanical properties of Ti_(1-x)Al_xN and Ti_(1-x-y)Al_xSi_yN metastable phase. Focus on the calculation of the Ti_(1-x-y)Al_xSi_yN the cohesive energy, mechanical constants, elastic modulus and shear modulus. These calculated values were analyzed, then we obtained that Ti_(1-x)Al_xN lattice parameter decreased after adding Si, while the cohesive energy was rising, the mechanical properties decreased, indicating that in the case of the Al content determined, the structure of Ti_(1-x-y)Al_xSi_yN is more stable than Ti_(1-x)Al_xN, but the mechanical performance, stiffness and brittleness are reduced.