Processing and characterization of boron carbide-aluminium composites

ABSTRACT PhD Thesis PRODUCTION AND CHARACTERISATION OF BORON CARBIDE-ALUMINIUM COMPOSITES GÜRSOY ARSLAN Anadolu University Graduate School of Natural and Applied Sciences Ceramic Engineering Program Supervisor: Assoc. Prof. Dr. Ferhat KARA 2001 In this thesis, production and characterization of light, dense and tough B4C-A1 composites that have been produced by the cost effective melt infiltration technique are undertaken. It was observed that B4C-A1 composites could be produced by reactive infiltration at a temperature range between 985° and 1370 "C in an Ar atmosphere. The phases present and their quantities in the composites were determined systematically by quantitative x-ray analysis. It was found that by changing infiltration conditions, particle size and surface chemistry of B4C particles the reaction rate between B4C and Al could be controlled. As a result of a reaction between B4C and Al, A13BC and A1B2 are the mainly forming phases. It is the A13BC phase that leads to the wetting of B4C by aluminium. The mechanical properties of the produced composites are observed to vary depending on the processing conditions but the properties can be controlled. Fracture toughness of composites is observed to increase with the increasing content of free aluminium and the size of ligaments. Ballistic testing of the composites has shown that they have a potential to be used as armour materials with multi-hit performance. Keywords: Infiltration, Wetting, Armour 11