Utilization of carbon fibers in thermal management of microelectronics

ABSTRACTIn contrast to the form in which other carbon fibers are produced, vapor grown carbon fiber (VGCF) is produced from gas phase precursors in the form of individual fibers of discrete lengths. VGCF can be harvested as a mat of semi-aligned, semicontinuous fibers, with occasional fiber branching and curling. The use of VGCF mats as reinforcement result in composites which exhibit unique microstructure and physical properties that are not observed in other types of carbon composites. This paper describes the processing of VGCF mats reinforced carbon composites, and its unique microstructure and properties. Utilization of fiber tensile properties, as well as thermal conductivity, in the composites is discussed. Comparison of experimental results from various VGCF composites to theory indicates that mechanical properties are more strongly affected by characteristics of VGCF mat than are thermal conductivity. The implications of this relationship favors applications for thermal management where structural demands are less stringent.

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Thermal management analysis of a Li-ion battery cell using phase change material loaded with carbon fibers

Energy ◽

10.1016/j.energy.2015.12.064 ◽

2016 ◽

Vol 96 ◽

pp. 355-371 ◽

Cited By ~ 119

Author(s):

Fereshteh Samimi ◽

Aziz Babapoor ◽

Mohammadmehdi Azizi ◽

Gholamreza Karimi

Keyword(s):

Phase Change ◽

Phase Change Material ◽

Thermal Management ◽

Carbon Fibers ◽

Li Ion Battery ◽

Battery Cell ◽

Li Ion ◽

Change Material

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Composites based on thermally hyper-conductive vapor grown carbon fiber

Journal of Materials Research ◽

10.1557/jmr.1995.1478 ◽

1995 ◽

Vol 10 (6) ◽

pp. 1478-1484 ◽

Cited By ~ 18

Author(s):

Jyh-Ming Ting ◽

Max L. Lake ◽

David R. Duffy

Keyword(s):

Thermal Conductivity ◽

Carbon Fiber ◽

Thermal Management ◽

Carbon Fibers ◽

Electronic Devices ◽

Aluminum Matrix ◽

Aluminum Matrix Composites ◽

Carbon Composites ◽

Matrix Composites ◽

A Value

Aluminum matrix composites and carbon/carbon composites based on vapor grown carbon fiber (VGCF) were fabricated for analysis of thermophysical properties. Due to the highly graphitic nature of VGCF, the resulting composites exhibit values of thermal conductivity that have not been achieved by using any other carbon fibers, and thus represent new materials for thermal management in applications such as packaging for high-power, high-density electronic devices. In the aluminum matrix VGCF composites, a thermal conductivity of 642 W/m-K was obtained by using a VGCF loading of only 36.5 vol.%. For VGCF/C composites, thermal conductivity of 910 W/m-K has been observed, a value which is more than a factor of two higher than that of copper. Based on the observed thermal conductivity of VGCF/Al composites and VGCF/C composites, the room temperature thermal conductivity of VGCF in the composite was calculated to be 1460 W/m-K and 1600 W/m-K, respectively.

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Thermal Profiles of Carbon Fiber Based Anisotropic Thin-Films: An Emerging Heat Management Solution for High-Current Flow Electrocatalysis and Electrochemical Applications

Catalysts ◽

10.3390/catal10101172 ◽

2020 ◽

Vol 10 (10) ◽

pp. 1172

Author(s):

Sang-Hwi Lim ◽

Han-Ki Kim

Keyword(s):

Thin Films ◽

Energy Storage ◽

Carbon Fiber ◽

Thermal Management ◽

Carbon Fibers ◽

Current Flow ◽

Phonon Transport ◽

High Current ◽

Heat Management ◽

Percolation Network

Carbon fiber has been extensively used in the photocatalysis, electrocatalysis and energy storage fields as supporting platform and conductive media. However, less attention has been paid with regards to its function in phonon transport and thermal management. We have investigated the effect of current flow direction on the heat management performance of carbon fiber based thin film heaters (CFTFHs) with anisotropic percolation network of carbon fibers (CFs). The anisotropic percolation network of carbon fibers (CFs) formed by roll-to-roll spray coating leads to the anisotropic electrical properties of CFs. As a result, CFs based thin films (CFTFs) have lower sheet resistance when measured parallel to the CFs alignment, compared to when they are aligned perpendicular. Because connectivity and current flow in CFs are critically dependent on the direction alignment of CFs, the saturation temperature (106.4 °C) of CFTFH with parallel aligned carbon fiber is higher than that (117.3 °C) of CFTFH with perpendicular alignment. Therefore, current flow in the same direction as the alignment of CFs is very important to achieve high-performance. Moreover, our study on thermal profile of anisotropic CFTFs under high current flows illustrates that carbon fiber thin films have great potential in thermal management solution for electrocatalytic and electrochemical energy storage applications.

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Application of Carbon Nanotubes and Fullerenes for Thermal Management in Ceramics

MRS Proceedings ◽

10.1557/proc-633-a17.4 ◽

2000 ◽

Vol 633 ◽

Author(s):

Leonard L. Yowell ◽

Brian M. Mayeaux ◽

Hsin Wang ◽

Enrique V. Barrera

Keyword(s):

Thermal Conductivity ◽

Carbon Nanotubes ◽

Thermal Management ◽

Carbon Fibers ◽

Tape Casting ◽

Laser Flash ◽

Flash Method ◽

New Techniques ◽

Walled Carbon Nanotubes ◽

Nanoscale Level

AbstractNew techniques for thermal management in ceramics at the nanoscale level have been investigated using low percentages of carbon nanotubes to reduce thermal conductivity of bulk ceramics. Samples of yttria-stabilized zirconia containing purified single-walled carbon nanotubes (SWNT) or vapor grown carbon fibers (VGCF) have been prepared by tape casting and analyzed using the laser flash method to evaluate reductions in thermal conductivity at high temperatures. New features in the samples due to the presence of carbon nanotubes have been characterized using Raman, SEM, TEM and, in the case of VGCFs, are related to significant reductions in thermal conductivity (>25%). The inclusion of a low percentage of nanoscale carbon fibers, the intimate relationship between the fibers and ceramic particles, and the indication that the fibers possess a crystalline overcoating, all contribute to the lowering of the thermal conductivity.

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Ribbon-shape carbon fibers for thermal management

Carbon ◽

10.1016/0008-6223(93)90196-h ◽

1993 ◽

Vol 31 (6) ◽

pp. 941-949 ◽

Cited By ~ 44

Author(s):

D.D. Edie ◽

C.C. Fain ◽

K.E. Robinson ◽

A.M. Harper ◽

D.K. Rogers

Keyword(s):

Thermal Management ◽

Carbon Fibers

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EXELFS Studies of Carbon Fibers

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100133953 ◽

1990 ◽

Vol 48 (2) ◽

pp. 72-73

Author(s):

V. Serin ◽

K. Hssein ◽

G. Zanchi ◽

J. Sévely

Keyword(s):

Carbon Fibers ◽

Energy Analysis ◽

Electron Excitation ◽

Complex Structures ◽

High Modulus ◽

Promising Technique ◽

X Ray ◽

Fine Structures ◽

X Ray Absorption

The present developments of electron energy analysis in the microscopes by E.E.L.S. allow an accurate recording of the spectra and of their different complex structures associated with the inner shell electron excitation by the incident electrons (1). Among these structures, the Extended Energy Loss Fine Structures (EXELFS) are of particular interest. They are equivalent to the well known EXAFS oscillations in X-ray absorption spectroscopy. Due to the EELS characteristic, the Fourier analysis of EXELFS oscillations appears as a promising technique for the characterization of composite materials, the major constituents of which are low Z elements. Using EXELFS, we have developed a microstructural study of carbon fibers. This analysis concerns the carbon K edge, which appears in the spectra at 285 eV. The purpose of the paper is to compare the local short range order, determined by this way in the case of Courtauld HTS and P100 ex-polyacrylonitrile carbon fibers, which are high tensile strength (HTS) and high modulus (HM) fibers respectively.

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