Molecular dynamics method to predict the effects of temperature and strain rate on mechanical properties of Aluminum/Copper superalloy

Abstract

Metal alloys are engineered materials designed to enhance mechanical performance. Achieving optimal mechanical properties through alloy composition has been the focus of extensive research. This study employs the meshless molecular dynamics method to investigate the influence of temperature, strain rate, and copper content on the mechanical properties of Aluminum/Copper (Al-Cu) superalloy. The research focuses on the variation of copper content from 1 to 20%, temperature from 300 to 600 K, and strain rates between 0.001 ps⁻¹ and 0.01 ps⁻¹, assessing their impact on the ultimate tensile strength (UTS) and elastic modulus of the alloy. The results show a significant enhancement in both UTS and elastic modulus with increasing copper content, with the UTS increasing by 359% and the elastic modulus by 281% when copper content rises from 1 to 20%. In contrast, increasing the temperature from 300 to 600 K results in a 31% reduction in UTS and an 18.9% decrease in elastic modulus, highlighting the sensitivity of these properties to thermal effects. Additionally, higher strain rates were found to improve both UTS and elastic modulus, with an 11.95% increase in UTS and an 8.34% increase in elastic modulus at the highest strain rate (0.01 ps⁻¹). These findings demonstrate the critical role of alloy composition, temperature, and strain rate in tailoring the mechanical properties of Al-Cu alloys, providing insights for optimizing the material for high-performance applications.