镁合金具有密度低、比强度高和导热性能良好等特点，但其强度和塑性较低，限制了工程应用。 为提升其综合性能，本研究以 ZK60 镁合金为基体，引入氧化锌包覆石墨烯(ZnO@GNPs)作为增强体，采用超声波辅助机械搅拌铸造法制备了质量分数为 0%、0.1%、0.3%、0.5%和 0.7%的 ZnO@GNPs/ZK60 复合材料。 利用金相显微镜、配备能谱仪的扫描电子显微镜、X 射线衍射仪、显微硬度计、微机控制电子万能试验机及激光导热仪对复合材料的微观组织、力学性能和导热性能进行了分析。 结果表明，适量的 ZnO@GNPs 能够均匀分布于镁基体中，有效促进晶粒细化并改善界面结合。当 ZnO@GNPs 含量为 0.7%时，复合材料的抗拉强度和伸长率分别达到 210 MPa 和 5.3%，较基体合金提高约 19.3%和 39.5%；当 ZnO@GNPs 含量为 0.5%时，硬度达到峰值 83.32 HV；当 ZnO@GNPs 含量为 0.3%时，复合材料的热导率达到峰值，为 112.19 W/(m·K)，较基体合金提高 13.7%，之后随含量增加而下降。 综合分析表明，ZnO@GNPs 通过弥散强化 、晶粒 细 化 、界面 强 化 及 降 低 界 面 热 阻 等 多 重 机 制 ，显著 改 善 了 ZnO@GNPs/ZK60 复合 材 料 的 力 学 性 能 和 导 热性能。

Magnesium alloys possess advantages such as low density, high specific strength, and good thermal conductivity, but their relatively low strength and ductility limit broader engineering applications. To enhance their overall performance, ZnO-coated graphene nanoplatelets (ZnO@GNPs) were introduced as reinforcements into a ZK60 magnesium alloy matrix. ZnO@GNPs/ZK60 composites containing 0 wt.%, 0.1 wt.%, 0.3 wt.%, 0.5 wt.%, and 0.7 wt.% ZnO@GNPs were fabricated via an ultrasonic-assisted mechanical stirring-casting method. The microstructure, mechanical properties, and thermal conductivity of the composites were examined via optical microscopy, scanning electron microscopy equipped with EDS, X-ray diffraction, microhardness testing, tensile testing, and laser flash analysis. The results show that appropriate additions of ZnO@GNPs are uniformly distributed within the magnesium matrix, effectively promoting grain refinement and improving interfacial bonding. When the ZnO@GNPs content reaches 0.7 wt.%, the ultimate tensile strength and elongation of the composite increase to 210 MPa and 5.3%, representing improvements of 19.3% and 39.5% over those of the base alloy, respectively. The hardness attains a peak value of 83.32 HV at 0.5 wt.% , whereas the highest thermal conductivity of 112.19 W/(m·K)is achieved at 0.3 wt.%, which is 13.7% higher than that of the ZK60 matrix. Overall, the enhancement in the mechanical and thermal properties is attributed to the combined effects of dispersion strengthening, grain refinement, improved interfacial bonding, and a reduction in the interfacial thermal resistance induced by the ZnO@GNPs.