First-principles calculation of mechanical properties of Ir-Rh alloy.

The lattice parameters, bulk modulus, shear modulus, Young's modulus and other mechanical constants of Ir-xRh (x=0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 12, 15, 17, 20, 22, 25, 27, 30) alloys were calculated by using the first-principles analysis method based on density functional theory. The calculation model is established by the virtual crystal potential function approximation method. The effect of Rh doping on the mechanical properties of Ir-Rh alloy was also analyzed from the electronic point of view by calculating the enthalpy change value, electron density of state and energy band structure. The results show that the strength and hardness of the material can be improved by doping a small amount of Rh in Ir. The peak point at Ir-5Rh decreases slightly and then continues to rise, reaching the maximum at Ir-10Rh, and the value is basically the same as that of Ir-5Rh. With the increase of Rh content, the absolute value of enthalpy changed gradually increased from 0.186 eV to 0.634 eV, and the thermodynamic stability of Ir-Rh alloy was improved. In addition, the density of states and band structure of Ir-Rh alloy show that the bond energy increases with the increase of Rh content, and the brittleness of Ir-Rh alloy increases gradually. [ABSTRACT FROM AUTHOR]