Mechanical properties of melt infiltrated boron carbide-aluminium composites

Abstract

Boron carbide (B4C)-aluminium (Al) composites were produced by melt infiltration of 2024-T3 series Al alloys into porous B4C compacts in the temperature range of 985 degrees -1370 degreesC under an inert atmosphere (Ar). 4-point bending strength measurements showed that the composite strength varies between 355 MPa and 460 MPa depending on the average B4C Particle size and the metal content of the composite. The scatter in strength values was found to decline with increasing metal content. The stress-strain curves of the respective composites indicate that the amount of plastic deformation increases with an increase in the metal content of the composite, as expected. The fracture toughness of the composites was found to vary between 11-16 MPa rootm. It is observed that the fracture toughness of the composites increases with increasing Al content and metal ligament diameter.