Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
1583055 | Materials Science and Engineering: A | 2008 | 5 Pages |
WC–Co hardmetals using different starting powders were densified by spark plasma sintering (SPS). Sintering cycles were performed at 1240 °C for the WC–12 wt.% Co–0.45 wt.% VC grade and 1280 °C for the WC–6 wt.% Co grade, applying a pressure of 60 MPa in combination with a heating rate of 100 °C/min. The influence of the carbon content and homogeneity of the starting powders on the final microstructure and mechanical properties was investigated. A thin graded surface layer is observed in case of slightly carbon deficient starting powder. Co agglomerates were observed in the SPS materials obtained from lower energetically multi-directionally mixed WC–Co powder, whereas a homogeneous microstructure was obtained when using attritor-milled or chemically synthesized WC–Co starting powder with adjusted carbon balance. The observed microstructures are related to the measured mechanical properties.