Article

Processing of Silicon Carbide-Boron Carbide-Aluminium Composites

Anadolu University, Department of Materials Science and Engineering, Iki Eylul Campus, 26480 Eskisehir, Turkey
Journal of the European Ceramic Society (Impact Factor: 2.95). 03/2009; 29:473–480. DOI: 10.1016/j.jeurceramsoc.2008.06.007

ABSTRACT The aim of this work was to shed light on the wetting mechanism in the SiC–B4C–Al system and to explore processing routes that enable infiltration
of Al alloys into these ceramic powder mixtures without the formation of the deleterious reaction product Al4C3. For this purpose, powder mixtures
consisting of SiC and pre-treated B4C were pressureless infiltrated with Al alloys at relatively low temperatures under an inert gas atmosphere.
Depending on the characteristics of the starting powders fully infiltrated composites were achieved in the temperature range of 935–1420 ◦C. It
was observed that addition of pre-treated B4C to SiC enabled complete infiltration of the ∼0.6 cm thick preforms. The bulk density of all produced
composites was >98% of the X-ray density. By controlling the surface chemistry and particle size of the starting powders as well as the processing
conditions, the wetting behaviour and reaction kinetics of this system could be tailored so as to render fully dense SiC–B4C–Al composites devoid
of Al4C3.

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Available from: Ayse Kalemtas, Aug 24, 2015
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    • "Arslan and Kalemtas [12] explored the possible processing routes that enable the infiltration of Al alloys into SiC and B 4 C mixtures without the formation of Al 4 C 3 and for this purpose, powder mixtures consisting of SiC and pre-treated B 4 C were pressureless infiltrated with Al alloys at relatively low temperatures under an inert gas atmosphere which was achieved in the temperature range of 935–1420 °C. Alptekin et al. [13] investigated the production of A6063/SiC–B 4 C hybrid composite using vacuum assisted block mould investment casting method porosity fraction of preforms was determined using Archimedes' test and are characterized using hardness tests, image analysis and SEM observations and EDX analysis. "
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    ABSTRACT: In this work, using stir casting technique 99.85% pure aluminum matrix was reinforced with graphite particles and boron carbide particles to study the effect of graphite and boron carbide reinforcement using mechanical testing and wear behaviour. Different volume fractions of boron carbide viz. 2.5%, 5% and 7.5% are incorporated into the alloy, maintaining the volume fraction of graphite as 2% for all proportions. The distributions of reinforcement are made uniform by using a mechanical stirrer attachment and the various compositions of metal matrix composite are casted for testing. Microstructural characterization studies performed on the different compositions of composite prepared shows a uniform distribution of B4C particles at microscopic scale with less porosity. Mechanical properties such as Micro-Vickers hardness test and compression strength are determined and tribological behaviour of the composite is studied using wear test. With 7.5% reinforcement of B4C particles, the hardness and compression strength are higher and the results of wear test demonstrates an increase in wear resistance with increase in B4C reinforcement.
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