▎ 摘　　要

Graphene nanoplatelets (GNPs) as reinforcement in the ceramic matrix is rising continuously due to their outstanding mechanical and lubricative properties. Herein, different compositions of GNPs (0.5-2 wt%) rein-forced alumina-titania coatings were prepared using atmospheric plasma spraying. The relative density of AT coating increased from 83% to 94% with just (1.5 wt%) addition of GNP. Consequently, mechanical properties i. e. hardness and elastic modulus were improved by similar to 77% and similar to 69% respectively. Fracture toughness also increased from 2.65 +/- 0.95 MPa.m(1/2) to 5.85 +/- 1.07 MPa.m(1/2). Furthermore, the seawater wear test, using a ball-on-disc tribometer revealed that the wear rate of AT coating decreased from similar to 11 x 10(-14) m(3)/Nm to similar to 4 x 10(-14) m(3)/Nm, whereas the coefficient of friction reduced from 0.33 +/- 0.05-0.16 +/- 0.03. The mechanisms involved to improve these properties, viz. GNP sandwiching, crack bridging, crack arrest, etc. GNP's multi-layers facilitated long-term lubricity and enhanced the wear resistance properties of the coatings.