Glass-ceramics (GCs) are preferred over glass or ceramics in certain optical applications including those requiring lower porosity than ceramics and higher transition temperatures than glass. However, due to its material heterogeneity, it is difficult to precisely control the microstructure in GCs to meet specific property targets. The chemical mechanism behind the microstructural changes in the two-phase heterogeneity has not yet been clearly elucidated. In this work, the continuous Reactive Force Field molecular dynamics nanoindentation algorithm was developed and used to study the mechanism of structural evolution during nanoindentation. It was found that crystalline phases (CP) had the maximum load at the same indentation depth. The number of point defects of CP was more than glass-crystalline phase (GCP) at the end of loading. However, after total unloading, the opposite was observed with the number of point defects in GCP more than that in CP. The details in GCP bonding indicated that the formation of irreversible supersaturated bonds hindered the healing of defects while promoting the annihilation of pores. The evolution of pores and the typical chemical changes of GCP in the nanoindentation process had also been explored, which proves to be helpful in understanding the behaviors of two-phase heterogeneous materials at the nanoscale.

在某些光学应用中，微晶玻璃 (GC) 优于玻璃或陶瓷，包括那些要求孔隙率低于陶瓷和转变温度高于玻璃的光学应用。然而，由于其材料的异质性，很难精确控制 GC 中的微观结构以满足特定的性能目标。两相异质性微观结构变化背后的化学机制尚未清楚阐明。在这项工作中，开发了连续反应力场分子动力学纳米压痕算法，并用于研究纳米压痕过程中的结构演化机制。发现结晶相（CP）在相同的压痕深度下具有最大载荷。在加载结束时，CP 的点缺陷数量多于玻璃晶相 (GCP)。然而，完全卸载后，观察到相反的情况，GCP 中的点缺陷数量大于 CP 中的点缺陷数量。GCP 键合的细节表明，不可逆过饱和键的形成阻碍了缺陷的愈合，同时促进了孔隙的湮灭。还探讨了纳米压痕过程中孔隙的演变和 GCP 的典型化学变化，这有助于理解纳米级两相异质材料的行为。