Recovering of Hardmetal Powder into Hardmetal Rods and Development of Gradient Properties

摘要

Large amounts of powder residues were produced during conventional powder metallurgical routes, namely during green powder machining of complex geometries. In order to recover these powder residues, they were separated and classified according to their particle size and binder composition. In the present work, hardmetal rods were processed partially with a pristine WC-10 wt% Co submicron grade powder mixture, and a powder residue from fine/medium grain size grades with varied cobalt contents and secondary carbides. Preliminary results using the same submicron grain size in combination with recovered grades with different cobalt content revealed a gradient of properties along the cylinder length. In the present case, the effect of varying both the composition and the grain size on the Co migration and development of the gradient properties will be investigated. Systematic chemical, structural, microstructural and mechanical characterization will be performed in the developed components.