The coalescence and melting process of different sizes and arrangements of Ag and Cu nanoparticles is studied through the molecular dynamics (MD) method. The results show that the twin boundary or stacking fault formation and atomic diffusion of the nanoparticles play an important role in the different stages of the heating process. At the beginning of the simulation, Cu and Ag nanoparticles will contact to each other in a very short time. As the temperature goes up, Cu and Ag nanoparticles may generate stacking fault or twin boundary to stabilize the interface structure. When the temperature reaches a critical value, the atoms gain a strong ability to diffuse and eventually melt into one liquid sphere. The coalescence point and melting temperature increase as cluster diameter increases. Moreover, the arrangement of Cu and Ag nanoparticles has a certain effect on the stability of the initial joint interface, which will affect subsequent coalescence and melting behavior.

中文翻译：

---

铜和银纳米粒子聚结和熔融过程的分子动力学模拟

通过分子动力学（MD）方法研究了不同尺寸和排列的Ag和Cu纳米粒子的聚结和熔融过程。结果表明，纳米晶的孪晶边界或堆垛层错的形成和原子扩散在加热过程的不同阶段起着重要作用。在模拟开始时，Cu和Ag纳米粒子将在很短的时间内相互接触。随着温度的升高，Cu和Ag纳米粒子可能会产生堆垛层错或孪晶边界以稳定界面结构。当温度达到临界值时，原子具有很强的扩散能力，最终融化为一个液体球。聚结点和熔化温度随团簇直径的增加而增加。而且，