固结过程中超细和纳米晶碳化钨粉末的快速粗化已经挑战了数十年的纳米结构硬质合金的生产。因此，将WC-Co复合材料与过渡金属的碳化物合金化以抑制烧结过程中WC晶粒的生长已成为一种普遍的做法。这篇综述讨论了各种WC晶粒生长方式，晶粒生长抑制的细节，并报道了晶粒生长抑制剂对硬质合金的组织和性能的影响的报道。比较了晶粒生长抑制剂在液相烧结过程中抑制WC晶粒生长的有效性，并描述了它们在纳米晶体材料烧结方面的局限性。在低共晶温度下晶粒生长抑制剂的有效性，在没有粘合剂相的情况下和在替代的粘合剂体系中进行分析。总结和分析了目前公认的晶粒生长抑制机理，该机理是基于在WC / Co晶界处碳化物相分离的薄膜。评价并以图形方式显示了晶粒长大抑制剂对WC-Co硬质合金力学性能的影响。
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The influence of grain growth inhibitors on the microstructure and properties of submicron, ultrafine and nano-structured hardmetals – A review
The rapid coarsening of ultrafine and nanocrystalline WC powders during consolidation has challenged the production of bulk nano-structured hardmetals for decades. In response, it has become common practice to alloy WC-Co composites with carbides of transition metals in order to inhibit the WC grain growth during sintering. This review discusses various WC grain growth modes, details of grain growth inhibition and reports on the influences of grain growth inhibitors on the microstructure and properties of hardmetals found in current literature. The effectiveness of grain growth inhibitors to suppress WC grain growth during liquid-phase sintering is compared, and their limitations, with regards to sintering of nano-crystalline materials, are described. The effectiveness of grain growth inhibitors at under-eutectic temperatures, in the absence of a binder phase and in alternative binder systems, is analyzed. Currently recognized mechanisms of grain growth inhibition, on the basis of segregating thin films of carbide phases at WC/Co grain boundaries, are summarized and analyzed. The influence of grain growth inhibitors on the mechanical properties of WC-Co hardmetals are evaluated and graphically presented.