Comparative study on carbon nanotube- and reduced graphene oxide-reinforced alumina ceramic composites

• Published in: Ceramics international Vol. 44; no. 7; pp. 8350 - 8357
• Main Authors: Shin, Jung-Hoo, Choi, Jonghyun, Kim, Miyoung, Hong, Seong-Hyeon
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.05.2018
• Subjects: Alumina; Carbon nanotube; Ceramic composite; Reduced graphene oxide; Spark plasma sintering; Carbon nanotube; Spark plasma sintering; Ceramic composite; Reduced graphene oxide; Alumina
• ISSN: 0272-8842; 1873-3956
• DOI: 10.1016/j.ceramint.2018.02.024

Single wall carbon nanotube (SWCNT) and reduced graphene oxide (RGO) reinforced alumina ceramic composites were fabricated, and their microstructure, interface between matrix and reinforcement, electrical, mechanical, and thermal properties were comparatively investigated. The homogeneous dispersion of SWCNT and RGO and nearly full densification (> 96% of theoretical density) were achieved by dimethylformamide (DMF) solvent and spark plasma sintering (SPS), respectively. The chemical bonding between alumina and reinforcements was examined by high resolution transmission electron microscopy (HRTEM) with electron energy loss spectroscopy (EELS) and X-ray photoelectron spectroscopy (XPS). Elastic modulus and hardness of Al2O3 composites decreased, but fracture toughness and flexural strength increased with addition of SWCNT and RGO. SWCNT outperformed RGO in flexural strength whereas RGO was better than SWCNT to improve the fracture toughness. SWCNT was more effective for high electrical conductivity and low percolation threshold than RGO. The thermal conductivity of both composites decreased compared to monolithic Al2O3 possibly due to the reduced phonon mean free path by defects and carbon contamination.