HRTEM and Nanoindentation Studies of Bulk WC Nanocrystalline Materials Prepared by Spark Plasma Sintering of Ball-Milled Powders

Abstract

In the present work, mechanical milling technique using a high-energy ball mill was employed for preparing of nanoscaled WC grains powders with an average grain size of 7 nm in diameters of WC. The present study demonstrates a successful consolidation process achieved at 1250 °C for sintering of ball-milled WC powders into full dense bulk buttons (above 99.6%), using SPS technique. The as-consolidated WC bulk nanocrystalline buttons revealed high hardness value (~24 GPa) with low elastic modulus (~332 GPa). Moreover, they possessed a high fracture toughness (15 MPa m1/2) that has never been reported for pure WC.