Effect of mechanical activation of WC-based powder on the properties of sintered alloys

OBRABOTKAMETALLOV MATERIAL SCIENCE Vol. 23 No. 1 2021 During sintering of powders at different mechanical activation times, WC- and Co-phases are formed, with the lattice parameter of the WC-phase corresponding to the tabulated value. The Co 3 W 3 C carbide phase is formed in the samples upon mechanical activation over 100 s. The average WC-phase grain size decreases from 1.1 μ m ( σ = 0.6 μ m) to 0.8 ( σ = 0.3 μ m) with increasing machining time. The minimum porosity corresponds to 7.8 ± 1 % at 30 s of powder processing. It is shown that the hardness depends on both the time of mechanical activation and the grain size, porosity, and content of Co 3 W 3 C carbide. Thus, mechanical activation can be effective for suppressing grain growth, but it should be carried out in the time interval of 60...100 s. References 1. Ryu T., Sohn H.Y., Hwang K.S., Fang Z.Z. Plasma synthesis of tungsten carbide and cobalt nanocomposite powder. Journal of Alloys and Compounds , 2009, vol. 481 (1–2), pp. 274–277. DOI: 10.1016/j.jallcom.2009.03.134. 2. Shon I.-J., Kim B.-R., Doh J.-M., Yoon J.-K., Woo K.-D. Properties and rapid consolidation of ultra-hard tung- sten carbide. Journal of Alloys and Compounds , 2010, vol. 489 (1), pp. L4–L8. DOI: 10.1016/j.jallcom.2009.09.040. 3. Lee G.-H., Kang S. Sintering of nano-sized WC-Co powders produced by a gas reduction-carburization pro- cess. Journal of Alloys and Compounds , 2006, vol. 419 (1–2), pp. 281–289. DOI: 10.1016/j.jallcom.2005.09.060. 4. Kim J.Y., Kang S.H. WC platelet formation via high-energy ball mill. International Journal of Refractory Met- als and Hard Materials , 2014, vol. 47, pp. 108–112. DOI: 10.1016/J.IJRMHM.2014.06.024. 5. Kim B.K., Ha G.H., Lee D.W. Sintering and microstructure of nanophase WC/Co hardmetals. Journal of Ma- terials Processing Technology , 1997, vol. 63, pp. 317–321. DOI: 10.1016/s0924-0136(96)02748-3. 6. Wang W., Lu Z., Zeng M., Zhu M. Achieving combination of high hardness and toughness for WC-8Co hard- metals by creating dual scale structured plate-like WC. Ceramics International , 2018, vol. 44 (3), pp. 2668–2675. DOI: 10.1016/j.ceramint.2017.10.190. 7. Stewart D.A., Shipway P.H., McCartney D.G. Microstructural evolution in thermally sprayed WC-Co coat- ings: comparison between nanocomposite and conventional starting powders. Acta Materialia , 2000, vol. 48 (7), pp. 1593–1604. DOI: 10.1016/s1359-6454(99)00440-1. 8. Fabijani ć T.A., Alar Ž., Ć ori ć D. In fl uence of consolidation process and sintering temperature on microstruc- ture and mechanical properties of near nano- and nanostructured WC-Co cemented carbides. International Journal of Refractory Metals and Hard Materials , 2016, vol. 54, pp. 82–89. DOI: 10.1016/j.ijrmhm.2015.07.017. 9. Kim H.-C., Shon I.-J., Yoon J.-K., Doh J.-M. Consolidation of ultra fi ne WC and WC-Co hard materials by pulsed current activated sintering and its mechanical properties. International Journal of Refractory Metals and Hard Materials , 2007, vol. 25 (1), pp. 46–52. DOI: 10.1016/j.ijrmhm.2005.11.004. 10. El-Eskandarany M.S. Structure and properties of nanocrystalline TiC full-density bulk alloy consolidated from mechanically reacted powders. Journal of Alloys and Compounds , 2000, vol. 305, pp. 225–238. DOI: 10.1016/ s0925-8388(00)00692-7. 11. Raihanuzzaman R.M., Xie Z.H., Hong S.J. Powder re fi nement, consolidation and mechanical properties of cemented carbides – an overview. Powder Technology , 2014, vol. 261, pp. 1–13. DOI: 10.1016/j.powtec.2014.04.024. 12. Koch C.C. Synthesis of nanostructured materials by mechanical milling: problems and opportunities. Nano- structured Materials , 1997, vol. 9, pp. 13–22. DOI: 10.1016/s0965-9773(97)00014-7. 13. Vega L.E.R., Leiva D.R., Leal Neto R.M., Silva W.B., Silva R.A., Ishikawa T.T., Botta W.J. Mechanical activation of TiFe for hydrogen storage by cold rolling under inert atmosphere. International Journal of Hydrogen Energy , 2018, vol. 43 (5), pp. 2913–2918. DOI: 10.1016/j.ijhydene.2017.12.054. 14. Zaluski L., Tessier P., Ryan D.H., Doner C.B., Zaluska A., Ström-Olsen J.O., Trudeau M.L., Schulz R. Amorphous and nanocrystalline Fe-Ti prepared by ball-milling. Journal of Materials Research , 1993, vol. 8 (12), pp. 3059–3068. DOI: 10.1557/jmr.1993.3059. 15. Mushnikov N.V., Ermakov A.E., Uimin M.A. Kinetics of interaction of Mg-based mechanically activated alloys with hydrogen. The Physics of Metals and Metallography , 2006, vol. 102 (4), pp. 421–431. DOI: 10.1134/ s0031918x06100097. 16. Stepanov A., Ivanov E., Konstanchuk I. Hydriding properties of mechanical alloys Mg-Ni. Journal of the Less-Common Metals , 1987, vol. 131, pp. 89–97. DOI: 10.1016/0022-5088(87)90504-2. 17. Sun J.F., Zhang F.M., Shen J. Characterizations of ball-milled nanocrystalline WC-Co composite powders and subsequently rapid hot pressing sintered cermets. Materials Letters , 2003, vol. 57, pp. 3140–3148. DOI: 10.1016/ S0167-577X(03)00011-9.