Functionally graded boron carbide and aluminum composites with tubular geometries using pulsed electric current sintering

A functionally graded boron carbide (B(4)C) with precipitous property and microstructural gradients has been synthesized using pulsed electric current sintering (PECS) in tubular shape forms. During PECS the amorphous powders react and partially consolidate forming a density gradient radially across the tube walls. Modeling results support the presence of a large radial temperature gradient sufficient to produce B4C in smoothly varying densities from inside to outside diameters. This material and geometry is both novel and of particular use in applications requiring a cylinder of differing surface structures that transition smoothly into a metallic substructure or assembly. (C) 2010 Elsevier B.V. All rights reserved.