Toughened and machinable glass matrix composites reinforced with graphene and graphene-oxide nano platelets

0421085 - ÚFM 2014 RIV NL eng J - Journal Article
Porwal, H. - Tatarko, Peter - Grasso, S. - Hu, Ch. - Boccaccini, A. R. - Dlouhý, Ivo - Reece, M.J.
Toughened and machinable glass matrix composites reinforced with graphene and graphene-oxide nano platelets.
Science and Technology of Advanced Materials. Roč. 14, č. 5 (2013), Art.N. 055007. ISSN 1468-6996. E-ISSN 1878-5514
EU Projects: European Commission(XE) 264526 - GLACERCO
Institutional support: RVO:68081723
Keywords : silica * graphene/graphene-oxide nanoplatelets * nanocomposites * mechanical properties * sintering
Subject RIV: JI - Composite Materials
Impact factor: 2.613, year: 2013

The processing conditions for preparing well dispersed silica–graphene nanoplatelets and silica–graphene oxide nanoplatelets (GONP) composites were optimized using powder and colloidal processing routes. Fully dense silica–GONP composites with up to 2.5 vol% loading were consolidated using spark plasma sintering. The GONP aligned perpendicularly to the applied pressure during sintering. The fracture toughness of the composites increased linearly with increasing concentration of GONP and reached a value of _0.9MPa m1/2 for 2.5 vol% loading. Various toughening mechanisms including GONP necking, GONP pull-out, crack bridging, crack deflection and crack branching were observed. GONP decreased the hardness and brittleness index (BI) of the composites by _30 and _50% respectively. The decrease in BI makes silica–GONP composites machinable compared to pure silica. When compared to silica–Carbon nanotube composites, silica–GONP composites show better process-ability and enhanced mechanical properties.
Permanent Link: http://hdl.handle.net/11104/0227585