Konyashin Igor, Zaitsev Alexander, Meledin Alexander, Mayer Joachim, Loginov Pavel, Levashov Evgeny, Ries Bernd
Department of Powder Metallurgy and Functional Coatings, National University of Science and Technology "MISiS", Leninsky pr. 4, 119049 Moscow, Russia.
Element Six GmbH, Städeweg 12-24, 36151 Burghaun, Germany.
Materials (Basel). 2018 Mar 9;11(3):404. doi: 10.3390/ma11030404.
Interfaces between alloys simulating binders in WC-Co cemented carbides and tungsten carbide were examined on the micro-, nano-, and atomic-scale. The precipitation of fine WC grains and η-phase occurs at the interface of the alloy with the low carbon content. The precipitation of such grains almost does not occur in the alloy with the medium-low carbon content and does not take place in the alloy with the high carbon content. The formation of Co nanoparticles in the binder alloy with the medium-low carbon content was established. Interfaces in the alloy with the medium-low carbon content characterized by complete wetting with respect to WC and with the high carbon content characterized by incomplete wetting were examined at an atomic scale. The absence of any additional phases or carbon segregations at both of the interfaces was established. Thus, the phenomenon of incomplete wetting of WC by liquid binders with high carbon contents is presumably related to special features of the Co-based binder alloys oversaturated with carbon at sintering temperatures.
在微米、纳米和原子尺度上研究了模拟WC-Co硬质合金中粘结剂的合金与碳化钨之间的界面。在低碳含量的合金界面处会出现细小WC晶粒和η相的析出。在中低碳含量的合金中几乎不会出现这种晶粒的析出，而在高碳含量的合金中则不会发生。已确定在中低碳含量的粘结剂合金中会形成钴纳米颗粒。在原子尺度上研究了中低碳含量合金中相对于WC完全润湿的界面以及高碳含量合金中不完全润湿的界面。已确定在这两个界面处均不存在任何额外相或碳偏析。因此，高碳含量的液态粘结剂对WC不完全润湿的现象可能与烧结温度下碳过饱和的钴基粘结剂合金的特殊特性有关。
