Study on the microscopic compression deformation mechanism of nanocrystalline single-phase gold platinum alloy

Abstract

Although the catalytic properties of Au–Pt alloys have received widespread attention, there are a few of relevant studies on their microscopic deformation process. Considering that Au–Pt alloys are noble metals, and the costs of experiments are extremely high. Direct research experiments are extremely expensive. So the molecular dynamics method which can directly observe the evolution process of microstructure and analyze the mechanical behavior of each deformation stage of the material was adopted to explore the underlined relationship between the temperature and the compression deformation mechanism. The results show that during the process of compression deformation, lots of atoms in the crystal are converted into boundary atoms, the dislocation multiplication and the grain fragmentation occur. In different temperature intervals, along with the compression deformation, low temperature, medium temperature and high temperature recovery appear. Due to the influence of the dual mechanism of deformation and recovery, the deformation mechanism is different at different temperatures, at low temperature stage is mainly the dislocation multiplication and the grain fragmentation, at middle temperature stage is the combination of the opposite sign dislocation, and at high temperature stage is mainly the merger of the grain.