Continuous SiC skeleton reinforced highly oriented graphite flake composites with high strength and specific thermal conductivity

Abstract

Highly oriented graphite-based composites have attracted great attention because of their high thermal conductivity (TC), but the low mechanical properties caused by the inhomogeneous distribution and discontinuity of reinforcements restrict the wide applications. Herein, continuous SiC ceramic skeleton reinforced highly oriented graphite flake (SiC/GF) composites were successfully prepared by combining vacuum filtration and spark plasma sintering. The effect of SiC concentration on the microstructure, flexural strength, and thermophysical properties of the composites was investigated. The GF grains in the composites exhibited high orientation with a Lotgering factor of > 88% when the SiC concentration was ⩽ 30 wt%, and the SiC skeleton became continuous with the SiC concentration reaching 20 wt%. The formation of continuous SiC skeleton improved the flexural strength of the composites effectively while keeping the TC in a high level. Especially, the composites with 30 wt% SiC exhibited the flexural strength up to 105 MPa, and the specific TC reaching 0.118 W·m2·K−1·kg·1. The composites with excellent flexural strength and thermophysical properties showed significant promise for thermal management applications.

Tunnel-structured willemite Zn2SiO4: Electronic structure, elastic, and thermal properties

“…of heat conductivity in Zn 2 SiO 4 , as density is much less temperature dependent than heat capacity and thermal diffusivity [76]. The minimum thermal conductivity experimentally determined is only 2.34 W/(m•K), which is close to that of the most common TBC materials, such as YSZ, La 2 Zr 2 O 7 , Y 2 Si 2 O 7 , β-Yb 2 Si 2 O 7 , etc.…”

Molten salt synthesis and antioxidation property of SiC‐coated mesocarbon microbeads

“…The experimental results illustrate the conspicuous improvement of antioxidation property of MCMB particles by SiC coatings. During the test, the oxidation reactions as following could take place in MCMB and SiC coating 33–35 : $$$$\begin{equation}{\rm{C(s)}} + {{\rm{O}}_{\rm{2}}}{\rm{(g)}} \to {\rm{C}}{{\rm{O}}_{\rm{2}}}{\rm{(g)}}\end{equation}$$$$ $$$$\begin{equation}{\rm{SiC(s) + 2}}{{\rm{O}}_{\rm{2}}}\left( {\rm{g}} \right) \to {\rm{C}}{{\rm{O}}_{\rm{2}}}\left( {\rm{g}} \right) +{\rm{Si}}{{\rm{O}}_{\rm{2}}}\left( {\rm{s}} \right)\end{equation}$$$$ $$$$\begin{equation}{\rm{SiC(s)}} + \frac{{\rm{3}}}{{\rm{2}}}{{\rm{O}}_{\rm{2}}}\left( {\rm{g}} \right) \to {\rm{CO}}\left( {\rm{g}} \right) +{\rm{Si}}{{\rm{O}}_{\rm{2}}}\left( {\rm{s}} \right).\end{equation}$$$$…”

“…The experimental results illustrate the conspicuous improvement of antioxidation property of MCMB particles by SiC coatings. During the test, the oxidation reactions as following could take place in MCMB and SiC coating [33][34][35] :…”

Large-Scale Fabrication of High-Performing Single-Crystal SiC Nanowire Sponges Using Natural Loofah

“…Silicon carbide nanowires (SiC nw ) have drawn extensive attention by virtue of their exclusive combined merits of fibers and ceramics. − As a one-dimensional material, they have unique physical–chemical properties of wide bandgap, high phonon/thermal conductivity, high dielectric loss, adjustable electrical conductivity, and photoluminescence, which endow them with great potential for state-of-the-art functional material applications in semiconductors, optoelectronics, bioimaging, wave-absorbing, electromagnetic shielding, energy storage, and catalysis. − On the other hand, as a ceramic material, they also feature excellent mechanical properties of low density, low thermal expansion, high modulus, high-temperature oxidation resistance, and hot corrosion resistance, which make them an ideal reinforcement in ceramics, metals, or polymer matrix structural materials to achieve the superior overall performance in strength, toughness, friction, creep resistance, and heat insulation under high temperature or extreme service conditions. − …”