High-Pressure Synthesis of cBN Nanoparticles with High-Density Nanotwin Substructures
High-Pressure Synthesis of cBN Nanoparticles with High-Density Nanotwin Substructures
复制标题
高压合成具有高密度纳米孪晶亚结构的立方氮化硼纳米颗粒
DOI：
10.1021/acsomega.9b03239
复制
发表时间：
2020
期刊：
影响因子：
4.1
通讯作者：
Tian Yongjun
中科院分区：
文献类型：
--
作者：
Ying Pan;Gao Yufei;Zhang Bin;Wu Yingju;Gao Guoying;Li Penghui;Li Zihe;Xu Bo;Hu Wentao;Zhao Zhisheng;He Julong;Yu Dongli;Tian Yongjun
立方氮化硼（cBN）与通常用作磨料和切削工具的其他陶瓷相比具有上级的硬度和强度。最近合成的具有超细纳米孪晶子结构的多晶cBN块体材料具有高硬度、断裂韧性和热稳定性的显着组合。孪晶亚结构具有与晶界相似的位错阻挡作用，导致材料的强化。迄今为止，具有超细纳米孪晶亚结构的cBN纳米粒子的合成尚未实现。在此，我们报道了在高压和高温下从洋葱状氮化硼（oBN）合成cBN纳米颗粒。多种表征方法，包括X射线衍射，拉曼光谱，和高分辨率透射电子显微镜，表明所制备的cBN纳米粒子含有高密度的纳米孪晶亚结构。高度褶皱的oBN前驱体的使用和设计良好的合成方法是获得这些独特的超细纳米孪晶cBN纳米颗粒的关键。
Cubic boron nitride (cBN) exhibits superior hardness and strength as compared with other ceramics that are commonly used as abrasives and cutting tools. The recently synthesized polycrystalline cBN bulk material with ultrafine nanotwin substructures possesses a remarkable combination of high hardness, fracture toughness, and thermal stability. The twin substructure has been demonstrated to exert dislocation-blocking effect similar to grain boundary, leading to strengthening of materials. So far, the synthesis of cBN nanoparticles with ultrafine nanotwin substructures has not yet been realized. Herein, we report on the synthesis of cBN nanoparticles from onion-like boron nitride (oBN) under high pressure and high temperature. Multiple characterization methods, including X-ray diffraction, Raman spectroscopy, and high-resolution transmission electron microscopy, revealed that the as-prepared cBN nanoparticles contained high-density nanotwin substructures. The use of the highly wrinkled oBN precursor and well-designed synthetic method were the key to obtain these unique ultrafine nanotwinned cBN nanoparticles.