Al2O3晶须与石墨烯纳米片共增强铜基复合材料的显微结构及界面行为(英文)

研究Al₂O₃晶须和石墨烯纳米片共增强铜基复合材料的力学性能和显微结构。采用机械合金化、真空热压烧结和热等静压工艺制备不同石墨烯含量的铜基复合材料。含0.5%石墨烯(质量分数)的铜基复合材料(GNP-0.5)具有良好的Cu/C和Cu/Al₂O₃界面结合性能；复合材料的硬度和抗压强度随石墨烯含量的增加呈现先增加到一个临界值后减小的趋势。研究结果表明，石墨烯和Al₂O₃晶须在铜基复合材料中最主要的强化机制是能量耗散和载荷传递以及石墨烯导致的晶粒细化。石墨烯与Al₂O₃晶须的双相混杂增强效应在于：当Al₂O₃/Cu界面存在微裂纹并沿着界面扩展时，嵌于铜基复合材料中的石墨烯会阻碍裂纹扩展路径，从而强化Al₂O₃晶须在铜基复合材料中的增强作用。

Microstructures and interfacial interactions of Al2O3 whiskers and graphene nano-platelets co-reinforced copper matrix composites

The mechanical properties and microstructures of Al₂O₃ whiskers and graphene nano-platelets (GNPs) co-reinforced Cu-matrix composites were studied. Cu-matrix composites with a variation of GNPs amount were fabricated by mechanical alloying followed by vacuum hot-pressing sintering and hot isostatic pressing. The Cu-matrix composite with 0.5 wt.% GNPs (GNPs-0.5) suggests a good interfacial bonding of both Cu/C and Cu/Al₂O₃ interfaces. Both the hardness and compressive strength of Cu-matrix composites show a consistent tendency that firstly increases to a critical value and then decreases with increasing GNPs amount. It is suggested that the most possible strengthening mechanisms of both GNPs and Al₂O₃ whisker working in the Cu-matrix composites involve energy dissipating and load transfer, as well as grain refinements for GNPs. The synergetic effect of GNPs and Al₂O₃ whiskers is highlighted that the embedded GNPs would hinder the crack path generated at the Al₂O₃/Cu interface and enhance the already outstanding strengthening effect that Al₂O₃ whiskers provide.