Powder roll-compaction process for controlling grain orientation texture and size in spark plasma sintered carbides

The objective of this work is to develop and evaluate a powder roll-compaction procedure for fabricating cemented carbides that enables control over its surface/sub-surface grain orientation texture and grain size. The primary motivation for this work is to gain the ability to impart spatial material (property) gradients in bulk hard materials and composites for the realization of bio-inspired designs of material-systems. For this study, measured mixtures of tungsten carbide (WC) and cobalt (Co) powders were subjected to pressurized roll-compaction operations to create (malleable) thin sheets, which were then stacked and spark plasma sintered to obtain bulk cemented WC-Co specimens. When using this procedure, it was observed through XRD results that the basal plane orientation texture was increased by about 21%, and that transitions in layer-by-layer carbide grain sizes could be reliably achieved.