Wire electrical discharge machinable SiC with GNPs and GO as the electrically conducting filler. Issue 8 (July 2019)

• Record Type: Journal Article
• Authors: Hanzel, Ondrej; Singh, Meinam Annebushan; Marla, Deepak; Sedlák, Richard; Šajgalík, Pavol
• Is Part Of: Journal of the European Ceramic Society. Volume 39:Issue 8(2019)
• Page Start: 2626
• Page End: 2633
• Publication Date: 2019-07
• Subjects: Silicon carbide -- Graphene nanoplatelets -- Graphene oxide -- Electrical conductivity -- Wire electro-discharge machining; Ceramic materials -- Periodicals; Composite materials -- Periodicals; Matériaux céramiques -- Périodiques; Composites -- Périodiques; Ceramic materials; Composite materials; Periodicals; Electronic journals; 666.05
• DOI: 10.1016/j.jeurceramsoc.2019.03.012
• Languages: English
• ISSNs: 0955-2219

Abstract

Abstract: SiC based composites filled with graphene nano-platelets (GNPs) or graphene oxide (GO) prepared by rapid hot-pressing exhibit sufficient electrical conductivity for their machinability by wire electro-discharge machining (WEDM). Composites microstructure anisotropy caused by graphene alignment as a consequence of rapid hot pressing was confirmed by measuring of electrical conductivity and thermal diffusivity. Electrical conductivity increased significantly with increased weight fraction of graphene in both measured directions. Highest value of 2031 S/m was obtained for composites with 15 wt. % of GNPs in parallel direction and only 1246 S/m in perpendicular direction to aligned GNPs. Thermal diffusivity is 63.3 mm 2 /s in parallel and only 23.3 mm 2 /s in perpendicular direction. The increase of the electrical conductivity has resulted in successful WEDM. The MRR was almost doubled when the filler concentration increased from 5 wt. % GNPs/GO to 15 wt. % GNPs. At the same time, the surface roughness decreased.