Interface thermal resistance and thermal conductivity of polymer composites at different types, shapes, and sizes of fillers: A review

Nonequilibrium molecular dynamics (NEMD) approach is developed to investigate the thermal transport across a solid-solid interface between two different materials with an interlayer around it. The effects of system size and the interlayer material’s properties on the interface thermal resistance are considered in our model. The NEMD simulations show that the addition of an interlayer between two highly dissimilar lattices depresses the interface thermal resistance effectively. Meanwhile, the effective thermal conductivity along the direction of heat flux is enhanced with the increasing system temperature. Moreover, the interface thermal resistance after including an interlayer does not depend strongly on the simulation system size.

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Study of Effective Thermal Conductivity of Glazed Hollow Bead Concrete

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.851.823 ◽

2016 ◽

Vol 851 ◽

pp. 823-828

Author(s):

Bing Zhang ◽

Zhong Qing Cheng

Keyword(s):

Thermal Conductivity ◽

Thermal Resistance ◽

Effective Thermal Conductivity ◽

Thermal Conductivity Coefficient ◽

Interface Thermal Resistance

Based on analyzing the mechanism of thermal conductivity of glazed hollow bead concrete, this paper divides the channels of thermal conductivity in concrete, constructs the model of thermal conductivity coefficient based on the Theory of Minimum Thermal Resistance, and confirms the model by using the data of other related literatures and the data of our own experiment. The consequence indicates that this model can calculate the thermal conductivity coefficient under arid state exactly. In order to improve the accuracy of this model, we should take the shape of framework, the interface thermal resistance between concrete and framework into consideration

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Composites for the 1990s

Philosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences ◽

10.1098/rsta.1987.0060 ◽

1987 ◽

Vol 322 (1567) ◽

pp. 409-423 ◽

Cited By ~ 27

Keyword(s):

Thin Film ◽

Mechanical Properties ◽

Thermal Conductivity ◽

Polymer Composites ◽

Laminated Composite ◽

Crack Arrest ◽

Unique Combination ◽

Different Types

Composites are of two essentially different types: ( a ) those made to achieve a unique combination of properties, usually mechanical properties; ( b ) composites formed for ease of processing. The archetype of ( a ) is the fibre or laminated composite. The attainable properties will be reviewed and interesting effects arising from the scale of size of the components discussed, notably crack arrest and thin-film effects. Examples of ( b ) are polymer-polymer composites and some of the processes for forming ceramics and strong metals. A unified example of ( a ) and ( b ) are composites of controlled thermal conductivity.

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Two-Step Raman Method for Interface Thermal Resistance and In-Plane Thermal Conductivity Characterization of Graphene Interface Materials

Volume 1: Heat Transfer in Energy Systems; Thermophysical Properties; Theory and Fundamentals in Heat Transfer; Nanoscale Thermal Transport; Heat Transfer in Equipment; Heat Transfer in Fire and Combustion; Transport Processes in Fuel Cells and Heat Pipes; Boiling and Condensation in Macro, Micro and Nanosystems ◽

10.1115/ht2016-7362 ◽

2016 ◽

Author(s):

Man Li ◽

Yanan Yue

Keyword(s):

Thermal Conductivity ◽

Thermal Resistance ◽

Graphene Film ◽

Phonon Transport ◽

Interfacial Thermal Resistance ◽

Transfer Model ◽

Interface Thermal Resistance ◽

Graphene Interface ◽

Interface Materials

The negative influence of substrate on in-plane phonon transport in graphene has been revealed by intensive research, whereas the interaction between phonons couplings across graphene/substrate interface and within graphene is still needed to figure out. In this work, we put forward a two-step Raman method to accomplish interface thermal resistance characterization of graphene/SiO2 and in-plane thermal conductivity measurement of supported graphene by SiO2. In order to calculate the interfacial thermal resistance, the temperature difference between graphene and its substrate was probed using Raman thermometry after the graphene film was uniformly electrically heated. Combing the ITR and the temperature response of graphene to laser heating, the thermal conductivity was computed using the fin heat transfer model. Our results shows that the thermal resistance of free graphene/SiO2 is enormous and the thermal conductivity of the supported graphene is significantly suppressed. The phonons scattering and leakage at the interface are mainly responsible for the reduction of thermal conductivity of graphene on substrate. The morphology change of graphene caused by heating mainly determines the huge interfacial thermal resistance and partly contributes to the suppression of thermal conductivity of graphene. This thermal characterization approach simultaneously realizes the non-contact and non-destructive measurement of interfacial thermal resistance and thermal conductivity of graphene interface materials.

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Effects of filler distribution and interface thermal resistance on the thermal conductivity of composites filling with complex shaped fillers

International Journal of Thermal Sciences ◽

10.1016/j.ijthermalsci.2020.106678 ◽

2021 ◽

Vol 160 ◽

pp. 106678

Author(s):

Xiaojian Wang ◽

Xiaohu Niu ◽

Xiaoxue Wang ◽

Xiaowei Qiu ◽

Liangbi Wang

Keyword(s):

Thermal Conductivity ◽

Thermal Resistance ◽

Interface Thermal Resistance ◽

Filler Distribution

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Interface Thermal Resistance and Length Effect on Thermal Conductivitiy of SWNT Bundles

Volume 7: Fluids and Heat Transfer, Parts A, B, C, and D ◽

10.1115/imece2012-89935 ◽

2012 ◽

Author(s):

Kasim Toprak ◽

Yildiz Bayazitoglu

Keyword(s):

Thermal Conductivity ◽

Thermal Resistance ◽

Effective Thermal Conductivity ◽

Volume Fraction ◽

Water Medium ◽

Interface Thermal Resistance ◽

Contact Points ◽

Length Fraction ◽

Vertically Aligned ◽

Packing System

Using different calculations and measurement methods, the results for the thermal conductivity in a single wall carbon nanotube (SWNT) are compared. Then, the interface thermal resistance effects on the effective thermal conductivity of multiple SWNTs in a hexagonal packing system submerged in oil, air, and water are studied. The results show that as the interface thermal resistance increases, the effective thermal conductivity decreases. Moreover, length, length fraction, and volume fraction effects on the thermal conductivity of the system submerged in a water medium are approximated by including the interface thermal resistances of the nanotube-matrix and nanotube-nanotube. The systems’ length ranged between 500–3000 nm. The created models contain either vertically aligned or non-straight nanotubes. Non-straight nanotubes systems make one or two contact points with other nanotubes. These contact points’ location vary based on the length ratio known as the length fraction. It is found that the effective thermal conductivity of the SWNT bundle has the highest value when they are uniformly aligned and dispersed without contact. As the density and length of the SWNTs increase, the effective thermal conductivity of the bundle system also increases.

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