Pressure infiltration casting process and thermophysical properties of high volume fraction SiCp/Al metal matrix composites

High volume fraction Aluminum/alumina-fused silica hybrid metal matrix composites containing alumina with 0, 10, 30 and 50 wt% fused silica were produced by melt squeezing casting method. Microstructure of hybrid composite was investigated by optical microscope and scanning electron microscopy (SEM). The SEM images showed uniform distribution of fused silica particles in composite microstructure. Also compressive strength of the composites changed (310-110 MPa) with amount of fused silica.

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Fabrication by SPS and Thermophysical Properties of High Volume Fraction SiCp/Al Matrix Composites

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.313.171 ◽

2006 ◽

Vol 313 ◽

pp. 171-176 ◽

Cited By ~ 6

Author(s):

X.F. Gu ◽

Lian Meng Zhang ◽

Mei Jun Yang ◽

Dong Ming Zhang

Keyword(s):

Thermophysical Properties ◽

Volume Fraction ◽

Coefficient Of Thermal Expansion ◽

High Volume ◽

High Volume Fraction ◽

Matrix Composites ◽

Sic Particles ◽

Plasma Sintering ◽

Spark Plasma ◽

Al Matrix Composites

SiCp/Al composites containing high volume fraction of SiC particles were fabricated by spark plasma sintering (SPS), and their thermophysical properties, such as thermal conductivity (TC) and coefficient of thermal expansion (CTE), were characterized. High relative density (R-D) of composites was successfully achieved through the optimization of sintering parameters, such as sintering temperature, sintering pressure and heating rate. The measured TCs of SiCp/Al composites fabricated by SPS are higher than 195W/m.k, no matter the volume fraction of SiC particles is high or low as long as the R-D is higher than 95%. The measured CTEs of SiCp/Al composites are in good agreement with the estimated values based on Kerner,s model. The high volume fraction of SiCp/Al composites are a good candidate material to substitute for conventional thermal management materials in advanced electronic packages due to its tailorable thermophysical properties.

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Diamond-Based Metal Matrix Composites for Thermal Management Made by Liquid Metal Infiltration — Potential and Limits

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.59.111 ◽

2008 ◽

Vol 59 ◽

pp. 111-115 ◽

Cited By ~ 68

Author(s):

Ludger Weber ◽

Reza Tavangar

Keyword(s):

Thermal Conductivity ◽

Metal Matrix Composites ◽

Metal Matrix ◽

Room Temperature ◽

Volume Fraction ◽

Coefficient Of Thermal Expansion ◽

Diamond Powder ◽

Matrix Composites ◽

Pressure Infiltration ◽

The One

Diamond-based metal matrix composites have been made based on pure Al and eutectic Ag-3Si alloy by gas pressure infiltration into diamond powder beds with the aim to maximize thermal conductivity and to explore the range of coefficient of thermal expansion (CTE) that can be covered. The resulting composites covered roughly the range between 60 and 75 vol-% of diamond content. For the Al-based composites a maximum thermal conductivity at room temperature of 7.6 W/cmK is found while for the Ag-3Si based composites an unprecedented value of 9.7 W/cmK was achieved. The CTE at room temperature varied as a function of the diamond volume fraction between 3.3 and 7.0 ppm/K and 3.1 and 5.7 ppm/K for the Al-based and the Ag-3Si-based composites, respectively. The CTE was further found to vary quite significantly with temperature for the Al-based composites while the variation with temperature was less pronounced for the Ag-3Si-based composites. The results are compared with prediction by analytical modeling using the differential effective medium scheme for thermal conductivity and the Schapery bounds for the CTE. For the thermal conductivity good agreement is found while for the CTE a transition of the experimental data from Schapery’s upper to Schapery’s lower bound is observed as volume fraction increases. While the thermophysical properties are quite satisfactory, there is a trade-off to be made in these materials between high thermal conductivity and low CTE on the one side and surface quality and machinability on the other.

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