Boron nitride nanosheets reinforced glass matrix composites

0450404 - ÚFM 2016 RIV GB eng J - Journal Article
Saggar, Richa - Porwal, H. - Tatarko, P. - Dlouhý, Ivo - Reece, M. J.
Boron nitride nanosheets reinforced glass matrix composites.
Advances in Applied Ceramics. Roč. 114, SEP (2015), S26-S32. ISSN 1743-6753. E-ISSN 1743-6761
R&D Projects: GA MŠMT(CZ) 7AMB14SK155
EU Projects: European Commission(XE) 264526
Institutional support: RVO:68081723
Keywords : Boron nitride nanosheets * Borosilicate glass * Mechanical properties
Subject RIV: JL - Materials Fatigue, Friction Mechanics
Impact factor: 1.162, year: 2015

The effect of reinforcing boron nitride nanosheets (BNNSs) on the mechanical properties of an amorphous borosilicate glass (BS) matrix was studied. The BNNSs were prepared using liquid exfoliation method and characterised by transmission electron microscopy, scanning electron microscopy and X-ray diffraction (XRD) analysis. The average length was 0.5 μm, and thickness of the nanosheets was between 4 and 30 layers. These BNNSs were used to prepare BS-BNNS composite with different loading concentrations of 1, 2.5 and 5 mass-% (i.e. 1.395, 3.705 and 7.32 vol.-%). Spark plasma sintering (SPS) was used to densify these composites to avoid structural damages to the BNNSs and/or crystallisation within the composite sample during high temperature processing. The BNNSs were found to be evenly distributed in the composites matrix and were found to be aligned in an orientation perpendicular to the direction of the applied force in SPS. The mechanical properties including fracture toughness, flexural strength and elastic modulus were measured. Both fracture toughness and flexural strength increased linearly with increasing concentration of BNNSs in BS glass. There was an enhancement of 45% in the fracture toughness (1.10 MPa.m1/2) as well as flexural strength (118.82 MPa) with the addition of only 5 mass-% loading of BNNSs compared to BS glass (0.76 MPa.m1/2; 82.16 MPa). The toughening mechanisms developed in the composites because of the reinforcement of BNNSs were thoroughly investigated.
Permanent Link: http://hdl.handle.net/11104/0251767