Graphene nanoplatelets (GNPs)-templated synthesis of oriented TiB and the inspiration for tailoring three-dimensional (3D) interface structure in GNPs/Ti matrix composites

Abstract This study reports on silicon nitride (Si3N4) and graphene nanoplatelets binary powder reinforced hybrid titanium composites obtained by a powder metallurgy method. Si3N4 powder was added at 3 wt.% and graphene nanoplatelets were added in various amounts (0.15, 0.30, 0.45, 0.60 wt.%) in the titanium matrix. Density, micro-Vickers hardness, compressive behavior, wear properties and microstructure of the hybrid composites were evaluated. Addition of different percentages of graphene nanoplatelets and 3 wt.% Si3N4 to the titanium matrix composites significantly enhanced mechanical properties. The highest hardness (634 HV) and compressive strength (1458 MPa) values were measured for 0.15 wt.% graphene nanoplatelets and 3 wt.% Si3N4 added titanium hybrid composite. The lowest mass loss and wear rate (Δm = 4 mg, W = 6.1×10–5 mm3 (N m)–1) values were measured for the same 0.15 wt.% graphene nanoplatelets and 3 wt.% Si3N4 added titanium hybrid composite compared with pure Ti.

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COMPUTATIONAL MICROSTRUCTURE-BASED ANALYSIS OF RESIDUAL STRESS EVOLUTION IN METAL-MATRIX COMPOSITE MATERIALS DURING THERMOMECHANICAL LOADING

Facta Universitatis Series Mechanical Engineering ◽

10.22190/fume201228011b ◽

2021 ◽

Vol 19 (2) ◽

pp. 241

Author(s):

Ruslan Balokhonov ◽

Varvara Romanova ◽

Eugen Schwab ◽

Aleksandr Zemlianov ◽

Eugene Evtushenko

Keyword(s):

Residual Stress ◽

Metal Matrix ◽

Spatial Scales ◽

Three Dimensional ◽

Matrix Composites ◽

Two Phase ◽

Irregular Shapes ◽

The Matrix ◽

Stress Formation ◽

Mechanical Fragmentation

A technique for computer simulation of three-dimensional structures of materials with reinforcing particles of complex irregular shapes observed in the experiments is proposed, which assumes scale invariance of the natural mechanical fragmentation. Two-phase structures of metal-matrix composites and coatings of different spatial scales are created, with the particles randomly distributed over the matrix and coating computational domains. Using the titanium carbide reinforcing particle embedded into the aluminum as an example, plastic strain localization and residual stress formation along the matrix-particle interface are numerically investigated during cooling followed by compression or tension of the composite. A detailed analysis is performed to evaluate the residual stress concentration in local regions of bulk tension formed under all-round and uniaxial compression of the composite due to the concave and convex interfacial asperities.

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Effect of Graphene Nanoplatelets Content on Dynamic Mechanical Property of GNPs/Ti Composites

Materials Science Forum ◽

10.4028/www.scientific.net/msf.910.123 ◽

2018 ◽

Vol 910 ◽

pp. 123-129 ◽

Cited By ~ 1

Author(s):

X.N. Mu ◽

H.N. Cai ◽

Hong Mei Zhang ◽

Q.B. Fan ◽

Y. Wu

Keyword(s):

Mechanical Properties ◽

Strain Rate ◽

Dynamic Stress ◽

Dynamic Compression ◽

Dynamic Mechanical Properties ◽

Graphene Nanoplatelets ◽

Matrix Composites ◽

Titanium Matrix ◽

Dynamic Mechanical ◽

Adiabatic Shearing

In this study, the titanium matrix composites (TiMCs) were fabricated by adding graphene nanoplatelets (GNPs). The dynamic compression test was carried out to study the effect of strain-rate and the GNPs content on dynamic mechanical properties of GNPs/Ti. Results show that the GNPs content (0wt%~0.8wt%) correspond to specific microstructure which affect the dynamic mechanical properties of the composites. Under high strain-rate (3500s-1), the 0.4wt%GNPs/Ti has the highest dynamic stress (~1860MPa) and strain (~30%). The adiabatic shearing band (ASB) microstructure of GNPs/Ti with various GNPs content has been observed under 3500s-1 strain-rate and the ASB microstructure evolution of 0.4wt%GNPs/Ti under different strain rate was investigated in particular.

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Preparation by solution mixing and characterization of condensation type poly(dimethyl siloxane)/graphene nanoplatelets composites

Journal of Composite Materials ◽

10.1177/00219983211055824 ◽

2021 ◽

pp. 002199832110558

Author(s):

Panayiotis Ketikis ◽

Efthimios Damopoulos ◽

Georgios Pilatos ◽

Panagiotis Klonos ◽

Apostolos Kyritsis ◽

...

Keyword(s):

Graphene Nanoplatelets ◽

Matrix Composites ◽

Dielectric Relaxation Spectroscopy ◽

X Ray Diffraction ◽

Scanning Calorimetry ◽

Melting Temperatures ◽

Dimethyl Siloxane ◽

Diffraction Patterns ◽

The Impact

The impact of the incorporation of graphene nanoplatelets (GN) on the properties of hydroxyl-terminated poly(dimethylsiloxane) (PDMS) matrices was investigated. The composites were prepared by solution mixing, using tetrahydrofuran (THF) as a solvent. Brookfield viscosimetry, implemented during the vulcanization process, revealed that GN increases the viscosity of the system, compared to pristine PDMS, proportionally to its concentration. X-ray diffraction patterns suggested an efficient dispersion of GN in the polysiloxane matrix. The D and G bands ratio (ID/IG) calculation, based on RAMAN spectra of GN/PDMS specimens, revealed more defects in graphene nanoplatelets when incorporated in the PDMS matrix. By differential scanning calorimetry (DSC), a marginal increase in crystallization, glass transition and melting temperatures of PDMS in GN/PDMS composites was observed. Improvement of the thermal stability of LMW PDMS composites, especially for higher GN concentrations (3 and 5 phr), was noticed by thermogravimetric analysis (TGA). Additionally, GN enhanced the tensile strength of composites, up to 73% for the 3 phr GN/LMW PDMS composite. A significant increase in the elongation at break was recorded, whereas no effect on the modulus of elasticity was recorded. The decrease in toluene-swelling, for the LMW PDMS matrix composites, was attributed to the increase in the tortuosity path because of the efficient dispersion of GN. A decrease in oxygen permeability of 55–65% and 44–58% was measured in membranes made of PDMS composites containing 0.5 phr and 1 phr GN, respectively. Dielectric relaxation spectroscopy (DRS) measurements recorded a significant increase in the conductivity of the higher graphene content composites.

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Konjac glucomannan-templated synthesis of three-dimensional NiO nanostructures assembled from porous NiO nanoplates for gas sensors

RSC Advances ◽

10.1039/c9ra00285e ◽

2019 ◽

Vol 9 (17) ◽

pp. 9584-9593 ◽

Cited By ~ 5

Author(s):

Le Lam Son ◽

Nguyen Duc Cuong ◽

Tran Thi Van Thi ◽

Le Trung Hieu ◽

Do Dang Trung ◽

...

Keyword(s):

Metal Oxide ◽

Gas Sensors ◽

Template Synthesis ◽

Three Dimensional ◽

Porous Metal ◽

Konjac Glucomannan ◽

Templated Synthesis ◽

Oxide Nanostructures ◽

Metal Oxide Nanostructures ◽

Highly Porous

Biopolymer template synthesis has attracted extensive interest for fabricating highly porous metal oxide nanostructures.

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Multi-interfaced graphene aerogel/polydimethylsiloxane metacomposites with tunable electrical conductivity for enhanced electromagnetic interference shielding

Journal of Materials Chemistry C ◽

10.1039/d0tc02278k ◽

2020 ◽

Vol 8 (34) ◽

pp. 11748-11759 ◽

Cited By ~ 6

Author(s):

Jingnan Ni ◽

Ruoyu Zhan ◽

Jun Qiu ◽

Jincheng Fan ◽

Binbin Dong ◽

...

Keyword(s):

Electrical Conductivity ◽

Microwave Absorption ◽

Electromagnetic Interference ◽

Three Dimensional ◽

Interface Structure ◽

Negative Permittivity ◽

Electromagnetic Interference Shielding ◽

Graphene Aerogel

Three-dimensional graphene aerogel/polydimethylsiloxane metacomposites with an integral multi-interface structure possess adjustable negative permittivity, excellent microwave absorption and electromagnetic interference shielding.

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