The squeeze infiltration process for fabrication of metal-matrix composites

Diamond particles are unique fillers for metal matrix composites because of their extremely high modulus, high thermal conductivity, and low coefficient of thermal expansion. Diamond reinforced aluminum metal matrix composites were prepared using a pressureless metal infiltration process. The diamond particulates are coated with SiC prior to infiltration to prevent the formation of Al4C3, which is a product of the reaction between aluminum and diamond. The measured thermal conductivity of these initial diamond/Al metal matrix composites is as high as 259 W/m-K. The effects of coating thickness on the physical properties of the diamond/Al metal matrix composite, including Young's modulus, 4-point bend strength, coefficient of thermal expansion, and thermal conductivity, are presented.

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Wear Characteristics of Particulate Reinforced Metal Matrix Composites Fabricated by a Pressureless Metal Infiltration Process

Materials Science Forum ◽

10.4028/www.scientific.net/msf.510-511.234 ◽

2006 ◽

Vol 510-511 ◽

pp. 234-237 ◽

Cited By ~ 3

Author(s):

Jae Dong Kim ◽

Hyung Jin Kim ◽

Sung Wi Koh

Keyword(s):

Wear Resistance ◽

Metal Matrix Composites ◽

Metal Matrix ◽

Volume Fraction ◽

Wear Loss ◽

Matrix Composites ◽

Slow Speed ◽

Infiltration Process ◽

Sliding Speed ◽

Metal Infiltration

The effect of size and volume fraction of ceramic particles with sliding speed on the wear properties were investigated for metal matrix composites fabricated by a pressureless metal infiltration process. The particulate metal matrix composites exhibited about 5.5 - 6 times greater wear resistance compared with AC8A alloys at high sliding speed, and by increasing the particle size and decreasing the volume fraction the wear resistance improved. The wear resistance of the metal matrix composites and AC8A alloy represented different aspects: the wear loss of the AC8A alloy increased with sliding speed linearly, whereas, the metal matrix composites displayed more wear loss than the AC8A alloy in the slow-speed region. However, a transition point of wear loss was found in the middle-speed region, which shows the minimum wear loss. Furthermore, wear loss in the high-speed region exhibited almost the same value as the slow-speed region. In terms of wear mechanism, the metal matrix composites showed abrasive wear at a slow to high sliding speed generally. However, the AC8A alloy showed abrasive wear at low sliding speed and adhesive and melt wear at a high sliding speed.

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Numerical Simulation of Pressure Infiltration Process for Making Metal Matrix Composites Using Dual-Scale Fabrics

Metallurgical and Materials Transactions A ◽

10.1007/s11661-013-1955-9 ◽

2013 ◽

Vol 44 (13) ◽

pp. 5834-5852 ◽

Cited By ~ 7

Author(s):

Bo Wang ◽

Krishna M. Pillai

Keyword(s):

Numerical Simulation ◽

Metal Matrix Composites ◽

Metal Matrix ◽

Matrix Composites ◽

Infiltration Process ◽

Pressure Infiltration ◽

Dual Scale

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Fluid-Structural Interaction Analysis of the MMC-Thixoforging Process

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.116-117.591 ◽

2006 ◽

Vol 116-117 ◽

pp. 591-595

Author(s):

Mathias Liewald ◽

Peter Unseld ◽

M. Schneider

Keyword(s):

Metal Matrix Composites ◽

Metal Matrix ◽

Interaction Analysis ◽

Rheological Behaviour ◽

Woven Fabrics ◽

Special Focus ◽

Matrix Composites ◽

Matrix Metal ◽

Infiltration Process ◽

Aerospace Applications

High mechanical properties in combination with low density are key features for lightweight constructions in automotive and aerospace applications. The combination between the innovative thixoforging process and the potential of fibre or particle strengthened composites with metallic matrices (MMCs) provides an efficient manufacturing process of structural components with continuous or gradient reinforcements. The scope of the Center of Competence for Casting and Thixoforging Stuttgart (CCT) contains new semi-solid manufacturing methods for metal matrix composites which have been developed and applied for patent pending. While previous research projects were focussed on fabrication of continuous fibre reinforced metal matrix composites, the local reinforcement insertion, located in the center of high force and torsion load zones, is going to be the next evolution step of the CCT research team. Therefore it is essential to verify, to simulate and to reproduce the process during infiltration of the semi-sold matrix metal into the textile layer experimentally. This paper illustrates investigations regarding the infiltration process of the thixotropic cast-alloys AlSi7Mg0.3 (A365) into laminated fibre woven fabrics by computational fluid dynamics and fluid-structure interaction analysis, taking account into specific manufacturing technology, the rheological behaviour of the alloy with special focus on infiltration behavior.

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