High Specific Strength Carbon Foam Prepared from Sucrose and Multi-Walled Carbon Nanotube

2015 ◽  
Vol 830-831 ◽  
pp. 545-548
Author(s):  
Rajaram Narasimman ◽  
Sujith Vijayan ◽  
Kuttan Prabhakaran
Keyword(s):  
Compressive Strength ◽  
Carbon Nanotube ◽  
Cellular Structure ◽  
Carbon Foam ◽  
Specific Strength ◽  
High Specific Strength ◽  
Multi Walled Carbon Nanotube ◽  
Uniform Dispersion ◽  
Carbon Foams ◽  
Maximum Compressive Strength

Multi-walled carbon nanotube (MWNT) reinforced carbon foams were prepared by thermo-foaming of MWNT dispersions in molten sucrose followed by dehydration and carbonization. The rheological studies showed that the uniform dispersion of MWNT was achieved up to 1.5 wt.%. The carbon foams showed cellular structure. The density of the carbon foams increased with an increase in the MWNT concentration up to 0.25 wt.% and then remained more or less constant. The maximum compressive strength of 4.9 MPa was achieved at the MWNT concentration of 0.5 wt.%.

scholarly journals Hybrid technology for manufacturing lightweight products with a cellular structure made of aluminum alloys

2021 ◽  
Vol 2077 (1) ◽  
pp. 012016
Author(s):  
A A Roslova ◽  
V A Izotov
Keyword(s):  
Aluminum Alloys ◽  
Porous Materials ◽  
Cellular Structure ◽  
Geometric Parameters ◽  
Low Density ◽  
Specific Strength ◽  
High Specific Strength ◽  
Material Part ◽  
Urgent Task ◽  
New Directions

Abstract This article is devoted to one of the new directions of creating and obtaining porous materials. The cellular material part is a new element that provides high specific strength of the structure in combination with low density. An urgent task is to develop and obtain a cellular structure with optimal geometric parameters to ensure maximum manufacturability of the structure. The obtained data can be used in the development of technological processes of hybrid casting technologies, as well as for the manufacture of new lightweight parts with increased specific strength characteristics.

Organo Modified Multi-Walled Carbon Nanotube Reinforced Pyridine Core Polybenzoxazine (MWCNT/PBZ) Nanocomposites

2015 ◽  
Vol 14 (05n06) ◽  
pp. 1550021
Author(s):  
S. G. Gunasekaran ◽  
K. Rajakumar ◽  
M. Dharmendirakumar
Keyword(s):  
Carbon Nanotube ◽  
Condensation Reaction ◽  
Absorption Bands ◽  
Weight Percentage ◽  
Morphological Studies ◽  
Mannich Condensation ◽  
Multi Walled Carbon Nanotube ◽  
Uniform Dispersion ◽  
Ft Ir ◽  
Diffraction Peaks

A new series of multi-walled carbon nanotube reinforced polybenzoxazine (MWCNT/PBZ) nanocomposites was successfully designed and developed. Three different maleimido terminal benzoxazine monomers (MI-BZs) were synthesized using N-(4-hydroxyphenyl) maleimide (HPM) and formaldehyde solution through Mannich condensation reaction and were characterized by FT-IR and NMR spectroscopy. Varying weight percentages (0 wt.%, 0.5 wt.%, 1.0 wt.% and 1.5 wt.%) of glycidyl-MWCNT were then incorporated into benzoxazine matrices to prepare MWCNT/PBZ nanocomposites. The nanocomposites having higher weight percentage of MWCNT were found to possess excellent thermal properties than those of neat PBZs. The developed nanocomposites exhibited better flame retardancy and higher dielectric constant. The optical properties ascertained from the UV-Vis absorption bands at the region of 300–350 nm and strong fluorescent emissions were observed in the wavelength range of 300–550 nm from Photoluminescence analysis. The intensity of characteristic diffraction peaks corresponding to g-MWCNT confirmed the reinforcement of MWCNT in the benzoxazine matrices, which indicated the successful formation of nanocomposites. The morphological studies ascertain the compatibility and uniform dispersion of MWCNT in the PBZ network.

Effects of Diluent on Mechanical Properties of Hollow Glass Microsphere Reinforced Epoxy Resin Composite

2016 ◽  
Vol 680 ◽  
pp. 525-528
Author(s):  
Hai Tao Geng ◽  
Jia Chen Liu ◽  
Sue Ren
Keyword(s):  
Mechanical Properties ◽  
Compressive Strength ◽  
Epoxy Resin ◽  
Resin Composite ◽  
Hollow Glass Microsphere ◽  
Hollow Glass Microspheres ◽  
Hollow Glass ◽  
Specific Strength ◽  
High Specific Strength ◽  
Epoxy Resin Composite

In order to improve the mechanical properties of hollow glass microspheres (HGMs) reinforced epoxy resin composite, diluent was added in the system of epoxy resin. The results revealed that more HGMs can be filled in the epoxy resin when appropriate amount diluent was added in the system, thus composite with relative low bulk density 0.70g/cm3 and high compressive strength 71.85MPa was obtained. It was due to that the diluent reduce the viscosity of the epoxy resin, which ensures uniform wetting of the fillers and enables more HGMs to be filled in resin. Besides, addition of diluent improved the adhesive strength between the epoxy resin and HGMs, making the composite having a relative high specific strength and can be used in weight sensitive filed.

Research on the Properties and Defects of Carbon Nanotubes

2014 ◽  
Vol 971-973 ◽  
pp. 157-160 ◽  
Author(s):  
A Ying Zhang
Keyword(s):  
Carbon Nanotubes ◽  
Tensile Strength ◽  
Elastic Modulus ◽  
Carbon Nanotube ◽  
Low Density ◽  
High Carbon ◽  
Specific Strength ◽  
Multi Walled Carbon Nanotube ◽  
Atomistic Models ◽  
The Individual

Carbon nanotube is one of the strongest materials in nature. Carbon nanotubes (CNTs) are the strongest and stiffest materials yet discovered in terms of tensile strength and elastic modulus respectively. This strength results from the covalent sp2bonds formed between the individual carbon atoms. A multi-walled carbon nanotube was tested to have a tensile strength of 63 gigapascals (GPa). Further studies revealed that individual CNT shells have strengths of up to ~100 GPa, which is in agreement with quantum/atomistic models. Since carbon nanotubes have a low density for a solid of 1.3 to 1.4 g/cm3, its specific strength of up to 48,000 kN·m·kg-1is the best of known materials, compared to high-carbon steel’s 154 kN·m·kg-1.

scholarly journals Correlation Analysis of Heat Curing and Compressive Strength of Carbon Nanotube–Cement Mortar Composites at Sub-Zero Temperatures

Crystals ◽  
2021 ◽  
Vol 11 (10) ◽  
pp. 1182
Author(s):  
Heeyoung Lee ◽  
Jongkyeong Seong ◽  
Wonseok Chung
Keyword(s):  
Compressive Strength ◽  
Carbon Nanotube ◽  
Ambient Temperature ◽  
Temperature Change ◽  
Maximum Temperature ◽  
Cementitious Composite ◽  
Mwcnt Content ◽  
Heat Curing ◽  
Multi Walled Carbon Nanotube ◽  
Experimental Parameters

Concrete curing under sub-zero temperatures causes various problems, such as initial cracking and a decrease in mechanical strength. This study investigated the effect of sub-zero ambient temperature and multi-walled carbon nanotube (MWCNT) content on the heat and strength characteristics of heat-cured MWCNT cementitious composites. The experimental parameters were the application of heat curing, MWCNT content, use of an insulation box to achieve a closed system, and ambient temperature. The results showed that the internal temperature change of the MWCNT cementitious composite increased with the ambient temperature and MWCNT content. When an insulation box was installed, the maximum temperature change of the MWCNT cementitious composite during curing increased. Furthermore, heat curing increased the compressive strength of the cementitious composite. Moreover, a microstructure analysis using field-emission scanning electron microscopy verified the formation of a MWCNT network among the cement hydrates.

Carbon Foams with High Compressive Strength Derived from Mixtures of Mesophase Pitch and Si Particles

2010 ◽  
Vol 97-101 ◽  
pp. 1130-1133
Author(s):  
Yang Wei Wang ◽  
Zhi Jin Zhang ◽  
Xiao Dong Yu ◽  
Fu Chi Wang ◽  
Kai Li ◽  
...  
Keyword(s):  
Compressive Strength ◽  
Carbon Foam ◽  
Mesophase Pitch ◽  
High Porosity ◽  
Strut Thickness ◽  
High Compressive Strength ◽  
Carbon Foams ◽  
Si Content ◽  
Si Addition ◽  
Pore Number

Carbon foam with relatively high compressive strength and high porosity was prepared from a mixture of mesophase pitch and Si particles by foaming and carbonization. The influence of Si content on the microstructures and properties of the carbon foam was studied. Results show that the pore number decreases and the strut thickness increases with an increasing of Si content. In addition, bulk density also increases with increasing Si content but the porosity decreases. Si addition to the mesophase pitch reduces the number of microcracks on the cell wall of the carbon foam remarkably which results in an increase of compressive strength for the carbon foams. Compressive strengths improve by 46%, 176% and 339% at Si additions of 30%, 40% and 50% (wt %), respectively. Carbon foam with a relatively high compressive strength of 24.6 MPa and a porosity of 61% are obtained when 50 wt% Si is added.

Properties of multi-walled carbon nanotube reinforced carbon foam composites

2010 ◽  
Vol 46 (4) ◽  
pp. 1143-1146 ◽  
Author(s):  
Wan Qian Li ◽  
Hong Bo Zhang ◽  
Xiang Xiong
Keyword(s):  
Carbon Nanotube ◽  
Carbon Foam ◽  
Multi Walled Carbon Nanotube

scholarly journals Mechanical Properties of Polymer Concrete

2013 ◽  
Vol 2013 ◽  
pp. 1-12 ◽  
Author(s):  
Raman Bedi ◽  
Rakesh Chandra ◽  
S. P. Singh
Keyword(s):  
Mechanical Properties ◽  
Compressive Strength ◽  
Processing Parameters ◽  
Vibration Damping ◽  
Machine Construction ◽  
Polymer Concrete ◽  
Curing Conditions ◽  
Specific Strength ◽  
High Specific Strength ◽  
Selection Of

Polymer concrete was introduced in the late 1950s and became well known in the 1970s for its use in repair, thin overlays and floors, and precast components. Because of its properties like high compressive strength, fast curing, high specific strength, and resistance to chemical attacks polymer concrete has found application in very specialized domains. Simultaneously these materials have been used in machine construction also where the vibration damping property of polymer concrete has been exploited. This review deals with the efforts of various researchers in selection of ingredients, processing parameters, curing conditions, and their effects on the mechanical properties of the resulting material.

Precipitation in Al-Li-Cu Alloys

1981 ◽  
Vol 39 ◽  
pp. 44-45
Author(s):  
J. E. O'Neal ◽  
K. K. Sankaran
Keyword(s):  
Electron Microscopy ◽  
Age Hardening ◽  
Precipitation Behavior ◽  
Zone Formation ◽  
Specific Strength ◽  
Hardening Behavior ◽  
Cu Alloys ◽  
High Specific Strength ◽  
Transmission Electron ◽  
Structural Applications

Al-Li-Cu alloys combine high specific strength and high specific modulus and are potential candidates for aircraft structural applications. As part of an effort to optimize Al-Li-Cu alloys for specific applications, precipitation in these alloys was studied for a range of compositions, and the mechanical behavior was correlated with the microstructures.Alloys with nominal compositions of Al-4Cu-2Li-0.2Zr, Al-2.5Cu-2.5Li-0.2Zr, and Al-l.5Cu-2.5Li-0.5Mn were argon-atomized into powder at solidification rates ≈ 103°C/s. Powders were consolidated into bar stock by vacuum pressing and extruding at 400°C. Alloy specimens were solution annealed at 530°C and aged at temperatures up to 250°C, and the resultant precipitation was studied by transmission electron microscopy (TEM).The low-temperature (≲100°C) precipitation behavior of the Al-4Cu-2Li-0.2Zr alloy is a combination of the separate precipitation behaviors of Al-Cu and Al-Li alloys. The age-hardening behavior at these temperatures is characteristic of Guinier-Preston (GP) zone formation, with additional strengthening resulting from the coherent precipitation of δ’ (Al3Li, Ll2 structure), the presence of which is revealed by the selected-area diffraction pattern (SADP) shown in Figure la.

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