Direct Ink Writing 3D Printing of Graphene/Al2O3 Composite Ceramics with Gradient Mechanics

A new graphene (G)/Al 2 O 3 composite ceramic with tunable mechanics is prepared by direct ink writing (DIW) 3D‐printing technology. It is found that the bending strength, fracture toughness, and hardness all increase with increasing in content of G. The bending strength, fracture toughness, and hardness of G/Al 2 O 3 composite ceramic (4.0 wt‰) are improved to be 45.0%, 40.6%, and 21.9% comparing to Al 2 O 3 ceramic, respectively. The result is attributed to good reinforcement of G and inhibition of Al 2 O 3 phase growth by G. Furthermore, the gear wheel with gradient mechanics is also designed and fabricated by the DIW 3D‐printing technology from various G/Al 2 O 3 composite gels. It exhibits excellent wear resistance and low generation of heat during rotational friction. Herein, a new method is provided to fabricate G‐based ceramics with gradient structure and mechanics for various applications.