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In order to compare the spark plasma sintering (SPS) process plus hot isostatic press (HIP) with vacuum sintering plus HIP, an investigation was carried out on the topography, microstructure and gain size distribution of nanocrystalline WC-l0Co com- posite powder and the sintered specimens prepared by SPS plus HIP and by vacuum sintering plus HIP by means of atomic force mi- croscopy (AFM). The mechanical properties of the sintered specimens were also investigated. It is very easy to find cobalt lakes in the specimen prepared by vacuum sintering plus HIP process. But the microstructure of the specimen prepared by SPS plus HIP is more homogeneous, and the grain size is smaller than that prepared by vacuum sintering plus HIP. The WC-10Co ultrafine cemented carbide consolidated by SPS plus HIP can reach a relative density of 99.4%, and the transverse rupture strength (TRS) is higher than 3540 MPa, the Rockwell A hardness (HRA) is higher than 92.8, the average grain size is smaller than 300 nm, and the WC-10Co ul- trafine cemented carbide with excellent properties is achieved. The specimen prepared by SPS with HIP has better properties and mi- crostructure than that prepared by vacuum sintering with HIP.
In order to compare the spark plasma sintering (SPS) process plus hot isostatic press (HIP) with vacuum sintering plus HIP, an investigation was carried out on topography, microstructure and gain size distribution of nanocrystalline WC-10Co com posite powder and the sintered instruments prepared by SPS plus HIP and by vacuum sintering plus HIP by means of atomic force mi-croscopy (AFM). The mechanical properties of the sintered specimens were also investigated. It is very easy to find cobalt lakes in the specimen prepared by vacuum sintering plus HIP process. But the microstructure of the specimen prepared by SPS plus HIP is more homogeneous, and the grain size is smaller than that prepared by vacuum sintering plus HIP. The WC-10Co ultrafine cemented carbide consolidated by SPS plus HIP can reach a relative density of 99.4%, and the transverse rupture strength (TRS) is higher than 3540 MPa, the Rockwell A hardness (HRA) is higher than 92.8, the average grain size is smaller than 30 0 nm, and the WC-10Co ul-trafine cemented carbide with excellent properties was achieved. The specimen prepared by SPS with HIP has better properties and mi- crostructure than that prepared by vacuum sintering with HIP.