▎ 摘　　要

The scratch resistance behaviour of alumina-graphene nanoplatelet (GNP) (0.5, 2 and 5 vol.-%) composites was investigated using a Rockwell indenter with normal applied loads ranging from 1 to 200 N. The alumina-GNP composites behaved differently during scratch testing depending on the normal applied load. The coefficient of friction of the composites did not change much at low normal loads but increased with increasing amount of GNP in the alumina matrix for high normal loads. The addition of GNP contributed to improved scratch resistance of alumina nanocomposites only for low loads below similar to 97 N. This correlates with the mechanical properties of the composites. As the applied load increased, the scratch resistance of the GNP composites decreased due to the presence of weakly bonded grain boundaries in the alumina matrix, which enhanced chipping of material.