The distribution characteristic of reinforcements is a critical issue for the final performance of magnesium matrix composites (MMCs). Here, the microstructural evolution of graphene nanoplatelets (GNPs) reinforced MMCs fabricated by thixomolding process was investigated. The GNPs successfully penetrated through the grain boundaries and embedded in two adjacent grains. Those intragranular GNPs/Mg interfaces not only could provide efficient barriers to pin dislocations, but also contribute to the multiplying dislocations to accumulate rather than dissipate. In addition, the finer MgO particles and elongated Mg₁₇Al₁₂ were anchored around the GNPs, which could effectively improve the interfacial load transfer due to the increased load-bearing capability and the effective interfacial shear strength. These special distribution characteristic of GNPs was beneficial to the significant enhancement of mechanical properties for the composites. The concept of intragranular reinforcements anchored by finer particles in this work may bring positive and directive significance for the structural design of the composites.

增强材料的分布特性是镁基复合材料 (MMC) 最终性能的关键问题。在这里，研究了通过触变成型工艺制造的石墨烯纳米片 (GNP) 增强 MMC 的微观结构演变。GNP 成功穿透晶界并嵌入两个相邻晶粒中。那些晶内 GNPs/Mg 界面不仅可以为 pin 位错提供有效的障碍，而且还有助于增加位错的积累而不是消散。此外，更细的 MgO 颗粒和细长的 Mg ₁₇ Al ₁₂被锚定在 GNPs 周围，由于增加了承载能力和有效的界面剪切强度，可以有效地改善界面载荷传递。GNPs的这些特殊分布特性有利于显着提高复合材料的力学性能。本工作提出的由更细颗粒锚固的晶内增强体的概念可能对复合材料的结构设计带来积极和指导意义。