Effect of Mo2C additions on the properties of SPS manufactured WC–TiC–Ni cemented carbides

Abrasion wear, thermal shock and impact resistance of WC-cemented carbides produced by PECS and LPS

“…The finer grain size of all the PECS 9.3Ni grades improved the hardness and abrasion resistance during sliding wear (Table 6) over the 9.3Ni (LPS) sample, which also had poorer binder distribution than the 9.3Ni (1430) sample (Fig. 1), giving lower K 1C [23] and TRS [28,29] (Table 6). The microstructure of the WC-0.5Cr 3 C 2 -5NbC-10Co (wt.%) (5N-s) (Fig.…”

“…An addition of 5 wt.% NbC to WC-0.5Cr 3 C 2 -10Co (wt.%) needed higher sintering temperature and pressure to achieve good densification, because NbC inhibits WC-Co densification during PECS [8]. Additions of TiC and Mo 2 C inhibit densification of WC-Ni cemented carbide during PECS [23], hence higher sintering pressures and temperatures are required. Good densification was achieved with increased sintering temperature since the solubility of WC in Ni and wetting of WC by Ni, as well as Mo solubility in Ni increases with sintering temperature [4,22].…”

“…This is evident in Figs. 1(c) and 3(a), where additions of Mo 2 C produced smaller and more evenly distributed Ni binder pools [23]. A higher sintering temperature (1380°C) was used for the WC-5Mo 2 C-6.25TiC-7Ni (wt.%) (5M-7Ni) samples than for WC-5Mo 2 C-6.25TiC-9.3Ni (wt.%) (5M) samples (1330°C), because of the reduced volume fraction of the lower melting point Ni binder (from 9.3 to 7 wt.%) [4,17].…”

“…This resulted in higher hardness and abrasion wear resistance of the 5N-s sample than 9.3Ni grades ( Table 6). The 5N-s sample had the highest K 1C and TRS for all the PECS WC-Ni samples, from the better wetting of WC by Co, facilitating better binder distribution [4,23], as well as the slightly higher binder proportion [4]. The good K 1C and TRS meant better thermal shock and impact resistance than the WC5Mo 2 C-6.25TiC-Ni (wt.%) (5 M-7Ni-u) insert.…”

Effect of Mo addition on the microstructure and properties of WC–Ni–Fe hard alloys

“…Due to the reasons mentioned above, considerable research efforts have been aimed at finding a satisfactory alternative binder phase. It has been shown that by using Ni instead of Co the corrosion and oxidation resistance of the resulting cemented carbide is improved; however, the mechanical properties are somewhat lower than those of WCeCo [8,9].…”