NET SHAPE AI/B4C METAL MATRIX COMPOSITES(MMCs)FOR HIGH SPECIFIC STIFFNESS AND NEUTRON ABSORPTION APPLICATIONS

摘要

Particle and fiber reinforced metal matrix composites(MMCs)have been evaluated over last fifty years for a multitude of applications. MMCs can combine desirable characteristics of metals(e.g. ductility, thermal conductivity)and ceramics(high hardness, high stiffness, low thermal expansion). In addition, B4C based MMCs offer neutron absorption capability for applications such as spent nuclear fuel storage. In this study AI/B4C MMCs with B_4C contents from 17 to 46% are made by a reactive infiltration approach. Process parameters such as matrix alloy and B4C volume fraction were systematically varied. Microstructure and properties(density, elastic modulus, tensile strength, and thermal conductivity)of the resultant composites were characterized. Correlations were drawn between the B4C content and properties. The ability to make net shape plates was demonstrated.