Preparation and mechanical properties of alumina composites reinforced with nickel-coated graphene

This paper discusses the influence of nickel-phosphorus coated graphene (Gn-Ni-P) and uncoated graphene (Gn) addition to an alumina matrix and its impact on the mechanical properties of obtained composites. The composites are prepared via powder processing and consolidated using the Spark Plasma Sintering (SPS) method. The effects of the addition of coated graphene and coating thickness on mechanical properties were evaluated. Physical properties such as relative density, hardness and fracture toughness were analyzed. Significant improvement of the fracture toughness (60%) for the composites with 2 vol% Gn-Ni-P compared to reference sample was observed. Moreover, 35% higher KIC was noticed for Gn-Ni-P reinforced composites than for Al2O3-Gn.