Tailoring the microstructure of an oriented ...
Document type :
Article dans une revue scientifique
Permalink :
Title :
Tailoring the microstructure of an oriented graphite flake/Al composite produced by powder metallurgy for achieving high thermal conductivity
Author(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]
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]
Journal title :
Diamond and Related Materials
Volume number :
118
Pages :
108513
Publisher :
Elsevier BV
Publication date :
2021-10
ISSN :
0925-9635
English keyword(s) :
Graphite flake/Al composite materials
Thermal conductivity
Powder filling process
Sintering
Thermal conductivity
Powder filling process
Sintering
HAL domain(s) :
Chimie/Matériaux
Physique [physics]/Matière Condensée [cond-mat]/Science des matériaux [cond-mat.mtrl-sci]
Physique [physics]/Matière Condensée [cond-mat]/Science des matériaux [cond-mat.mtrl-sci]
English abstract : [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 ...
Show more >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.Show less >
Show more >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.Show less >
Language :
Anglais
Peer reviewed article :
Oui
Audience :
Internationale
Popular science :
Non
Administrative institution(s) :
Université de Lille
CNRS
INRA
ENSCL
CNRS
INRA
ENSCL
Collections :
Research team(s) :
Métallurgie Physique et Génie des Matériaux
Submission date :
2021-06-30T07:31:22Z
2021-07-02T13:41:31Z
2021-07-02T13:41:31Z