Titre :

Tailoring the microstructure of an oriented graphite flake/Al composite produced by powder metallurgy for achieving high thermal conductivity

Auteur(s) :

Shen, Zhengyan [Auteur]
Institut de Chimie de la Matière Condensée de Bordeaux [ICMCB]
Unité Matériaux et Transformations - UMR 8207 [UMET]
Ji, Gang [Auteur]
Unité Matériaux et Transformations (UMET) - UMR 8207
Addad, Ahmed [Auteur]
Unité Matériaux et Transformations (UMET) - UMR 8207
Labrugere, Christine [Auteur]
Lu, Yongfeng [Auteur]
Silvain, Jean-François [Auteur]

Titre de la revue :

Diamond and Related Materials

Numéro :

118

Pagination :

108513

Éditeur :

Elsevier BV

Date de publication :

2021-10

ISSN :

0925-9635

Mot(s)-clé(s) en anglais :

Graphite flake/Al composite materials
Thermal conductivity
Powder filling process
Sintering

Discipline(s) HAL :

Chimie/Matériaux
Physique [physics]/Matière Condensée [cond-mat]/Science des matériaux [cond-mat.mtrl-sci]

Résumé en anglais : [en]

An Al matrix composite reinforced with 40 vol% graphite flake (Gf) was developed by powder metallurgy as a promising candidate for thermal management applications. Thermal conductivity (TC) along the orientation direction ...
Lire la suite >An Al matrix composite reinforced with 40 vol% graphite flake (Gf) was developed by powder metallurgy as a promising candidate for thermal management applications. Thermal conductivity (TC) along the orientation direction of the composite sintered at 640 °C was measured to be 452 W/m K, which is approximate to the highest TC value theoretically predicted by effective medium approximation model. The three underlying mechanisms responsible for such TC enhancement were clarified in terms of microstructure characterization. First, heat treatment of as-received Gf under Ar + H2 atmosphere resulted in reduction of defects on the edge contributing to improvement of interface thermal exchange efficiency between Al and Gf. Second, image analysis quantitatively confirmed that a step-by-step die filling process using the spherical powder ensures the perfect orientation of Gf in the Al matrix. Third, it was found that the TC of the composite increases with the sintering temperature from 580 to 640 °C. The formation of a small amount of fine platelet-like Al4C3 at the interface between the side surface of Gf and Al matrix indicates the desirable bonding state for minimizing interfacial thermal resistance, beneficial for the overall TC enhancement. Besides, the relevant coefficient of thermal expansion and bending strength were discussed.Lire moins >

Langue :

Anglais

Comité de lecture :

Oui

Audience :

Internationale

Vulgarisation :

Non

Établissement(s) :

Université de Lille
CNRS
INRA
ENSCL

Collections :

• Unité Matériaux et Transformations (UMET) - UMR 8207

Équipe(s) de recherche :

Métallurgie Physique et Génie des Matériaux

Date de dépôt :

2021-06-30T07:31:22Z
2021-07-02T13:41:31Z