PRESSURELESS-SINTERED BORON NITRIDE WITH LIMITED CONTENT OF BORIC OXIDE
PRESSURELESS-SINTERED BORON NITRIDE WITH LIMITED CONTENT OF BORIC OXIDE
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氧化硼含量有限的无压烧结氮化硼
DOI：
10.2472/jsms.44.507appendix_209
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发表时间：
1995
期刊：
影响因子：
--
通讯作者：
M. Ueki
中科院分区：
文献类型：
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作者：
M. Hubácek;M. Ueki
将单质硼和氮化硼粉末混合并在氮气中无压烧结。研究了陶瓷的结构和机械参数，并与不含元素硼的氮化硼粉末获得的陶瓷进行了比较。发现添加硼对增加密度、机械强度和耐火度以及抑制氮化硼晶粒的生长具有积极作用。这些变化的原因可以通过硼控制的氧化硼 (B2O3) 萃取过程中形成的化学式为 B6O 的难熔低氧化物来解释。提取原本附着在氮化硼颗粒表面的三氧化二合物，可以更有效地形成氮化硼陶瓷骨架。从陶瓷的形态来看，表明挥发性低氧化硼 (B2O2) 的形成先于氧在 B6O 晶粒中的局域化。
Elemental boron and boron nitride powders were mixed and pressureless-sintered in nitrogen. The structure and mechanical parameters of the ceramics were investigated and compared with those obtained from boron nitride powder free of the elemental boron. A positive effect of the addition of boron was found in increasing density, mechanical strength and refractoriness, and in suppressing growth of boron nitride grains. The reason of these changes has been explained by the formation of a refractory suboxide with a formula B6O as a consequence of a boron-controlled extraction of boric oxide (B2O3). The extraction of the sesquioxide being originally adhered to the surface of boron nitride grains allowing a more effective formation of boron nitride ceramic skeleton. From the morphology of the ceramics, it has been suggested that the formation of volatile boron suboxide (B2O2) precedes to localization of oxygen in B6O grains.