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

摘要

A functionally graded boron carbide (B_4C) 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 B_4C 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.