| 引用本文: | 王鹏,吴一,姜铸锋,刘洋,钟生林.溶胶凝胶-液态熔盐静电自组装复合工艺制备cBN@Al核壳粉体[J].中国表面工程,2019,32(6):157~164 |
| WANG Peng,WU Yi,JIANG Zhufeng,LIU Yang,ZHONG Shenglin.Preparation of cBN@Al Microparticle by Composite Process Regarding Sol-gel Molten Salt Self-assembly[J].China Surface Engineering,2019,32(6):157~164 |
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| 摘要: |
| 机械混合的cBN和金属Al粉是制备超硬切削刀具的重要原料，因此能有效提高两者接触面积的金属Al包覆cBN的核壳粉体具有潜在的经济价值。提出了一种先将cBN粉体表面羟基化，再通过溶胶-凝胶法对cBN表面进行硅氧纳米层改性，然后在熔融盐条件下包覆金属Al壳层，最后将核壳产物提纯的工艺路线。在不同条件的热处理和不同热处理时间下制备样品，并通过XRD、DSC、SEM、TEM和N2等温吸附脱附测试，探讨对包覆的影响因素及其机理。结果表明：基于布朗运动和静电自组装机制形成了多孔结构的包覆层，硅氧桥接层、导电熔融盐环境和热处理时间都对包覆Al壳层有重要影响。热处理2 h可获得平均粒径5.7 μm和比表面积10.988 m2/g且含杂质较少的cBN@Al多孔粉末。该项工作为在惰性无机粉末上涂覆活泼的轻金属壳层提供了新的思路。 |
| 关键词: 立方氮化硼 溶胶-凝胶 硅氧层 熔盐法 自组装 核壳结构 |
| DOI：10.11933/j.issn.1007-9289.20190308004 |
| 分类号:TB333 |
| 基金项目:广西创新驱动发展专项资金项目（AA17204098） |
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| Preparation of cBN@Al Microparticle by Composite Process Regarding Sol-gel Molten Salt Self-assembly |
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WANG Peng1, WU Yi1, JIANG Zhufeng2, LIU Yang1, ZHONG Shenglin1
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1.School of Materials Science and Engineering, Guilin University of Technology, Guilin 541004, China;2.College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Soochow 215123, China
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| Abstract: |
| cBN and Al powder are important raw materials for preparing ultra-hard cutting tools. Therefore, Al shell-coated cBN powders that can effectively improve the contact area between the two materials have potential economic value. A process route was proposed, in which the surface of cBN powder was hydroxylated and modified by silicon-oxide nanolayer with sol-gel process, the metal aluminum shell was then then coated with molten salt, and finally the core-shell products were purified. The samples which were prepared under different heat treatment conditions and times, characterized by DSC, XRD, SEM, TEM and N2 absorption-desorption. The influencing factors and the mechanism of the coating were discussed. Results show that the coating of the porous structure is formed owing to the Brownian motion and the electrostatic self-assembly mechanism. The siliceous bridging layer, conductive molten salt environment and heat treatment time all have important effects on the cladding of the aluminum shell. After heat treatment 2 h, the cBN@Al porous powder with an average particle size of 5.7 μm, a specific surface area of 10.988 m2/g and less impurities can be obtained. This work provides a new strategy for coating active light metal shell on inert inorganic powder. |
| Key words: cubic boron nitride sol-gel silica layer molten salt process self-assembly core-shell structure |
