TANG Run, LIU Hongjun, LI Yamin
(State Key Laboratory of Advanced Processing and Recycling of Non-ferrous Metals, Lanzhou University of Technology, Lanzhou 730050, Gansu, China)
Abstract: Graphene/SiCp/PCS slurry was obtained by adding graphene/SiCp composite powder into polycarbosilane (PCS) solution of silicon carbide precursor. Graphene/SiCp/SiC composites were prepared by direct ink writing 3D printing (DIW) and high temperature sintering. PCS has different products and properties at different pyrolysis temperatures. In this paper, the effect of pyrolysis temperature on the properties of graphene/SiCp/SiC composites was studied. PCS is converted into amorphous SiCxOy at 800 ℃. As the temperature increases to 1500 ℃, β-SiCand free carbon with higher conductivity were gradually formed from the amorphous SiCxOy. Theconductivity of graphene/SiCp/SiC composites increases from 0.93 S·m−1 to 670 S·m−1. At 1200 ℃, the compressive strength and bulk density of the composites reached the maximum of 12.3 MPa and 1.49 g·cm−3, respectively. This study provides a method to prepare highly conductive lightweight porous graphene/SiCp/SiC composite ceramics by direct writing 3D printing process based on PCS slurry.
Key words:3D printing; direct ink writing;pyrolysis temperature; graphene/SiCp/SiCcomposites; compressive strength; conductivity