Analytical solution for estimation of temperature-dependent material properties of metals using modified morse potential

Abstract

Summary An atomic-level analytical solution, together with a modified Morse potential, has been developed to estimate temperature-dependent thermal expansion coefficients (CTE) and elastic characteristics of bulk metals. In this study, inter-atomic forces are considered as a set of anharmonic oscillator networks which can be described by Morse potential, while the material properties can be defined by these inter-atomic forces; when temperature increases, the vibration of the anharmonic oscillator causes the phenomenon of temperature-dependent material properties. The results of analysis showed that the original Morse potential can give a reasonable prediction of the thermal expansion coefficients and elastic constants of metals at room temperature; however, it has difficulties in giving an accurate result at low and high temperatures. Therefore, to overcome the deficiency, a temperaturedependent modified Morse potential is developed and validated with various metals.