Enhancement of oxidation resistance via a self-healing boron carbide coating on diamond particles.
Enhancement of oxidation resistance via a self-healing boron carbide coating on diamond particles.
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通过金刚石颗粒上的自修复碳化硼涂层增强抗氧化性
DOI：
10.1038/srep20198
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发表时间：
2016-02-02
影响因子：
4.6
通讯作者：
Zheng W
中科院分区：
文献类型：
--
作者：
Sun Y;Meng Q;Qian M;Liu B;Gao K;Ma Y;Wen M;Zheng W
通过加热由H3BO3、B和Mg组成的粉末混合物中的颗粒，在金刚石颗粒上涂覆碳化硼涂层。研究了金刚石颗粒表面碳化硼涂层的组成、结合状态和覆盖率。碳化硼涂层倾向于生长在金刚石(100)表面，而不是金刚石(111)表面。在1200℃下保温2 h后，化学计量比的B4C涂层完全覆盖了金刚石颗粒，研究了碳化硼涂层对金刚石颗粒抗氧化性能的影响。涂层金刚石在空气中退火时，形成了具有自愈合性能的B_2O_3，作为氧阻挡层，保护了金刚石的氧化。B_2O_3的形成温度取决于无定形碳化硼的含量。在1000℃空气中加热1h，金刚石表面的涂层对金刚石的氧化起到了有效的保护作用，此外，碳化硼涂层的存在也有助于在金刚石在空气中退火的过程中保持静态抗压强度。
A boron carbide coating was applied to diamond particles by heating the particles in a powder mixture consisting of H3BO3, B and Mg. The composition, bond state and coverage fraction of the boron carbide coating on the diamond particles were investigated. The boron carbide coating prefers to grow on the diamond (100) surface than on the diamond (111) surface. A stoichiometric B4C coating completely covered the diamond particle after maintaining the raw mixture at 1200 °C for 2 h. The contribution of the boron carbide coating to the oxidation resistance enhancement of the diamond particles was investigated. During annealing of the coated diamond in air, the priory formed B2O3, which exhibits a self-healing property, as an oxygen barrier layer, which protected the diamond from oxidation. The formation temperature of B2O3 is dependent on the amorphous boron carbide content. The coating on the diamond provided effective protection of the diamond against oxidation by heating in air at 1000 °C for 1 h. Furthermore, the presence of the boron carbide coating also contributed to the maintenance of the static compressive strength during the annealing of diamond in air.