合成工艺对粉末冶金法制备AlB_12粉末的影响

Preparation of AlB_(12) powder by powder metallurgy method

采用不同合成工艺，利用铝粉和无定形硼粉制备A1B12粉末。在热力学分析的基础上，指出利用无定形硼粉和铝粉制备A1B12粉末的过程中铝粉表面形成的氧化物膜是产物中杂质的主要来源。结合质量损失率、X射线衍射图谱及扫描电镜分析，比较了三种不同合成工艺对合成产物中物相种类、杂质含量的影响，分析表明：采用自制坩埚、适量埋粉和高纯氩气保护相结合的方法能有效阻止氧的侵袭，降低氧化物杂质含量，提高所制取A1B12粉末的纯度，粉末颗粒均匀，平均粒径为1～2μm。

A1B12 powders were prepared by different synthesis technology using amorphous boron powder and aluminium powder as raw materials. On the basis of thermodynamic analysis, it was indicated that foreign substance of products came from mainly oxide film of aluminitum powder surface generated in A1B12 preparation process making use of amorphous boron powder and aluminium powder. The effects of three different synthesis technologies on phases and foreign substance contents of products were analyzed and compared based on mass loss rate, X - ray diffraction and SEM. The analysis results show that adopting home made crucibles, proper powder bed and high pure Ar2 atmosphere protection, the invasion of oxygen could be inhibited, and contents of oxide could be reduced to improve purity of A1B12 powder prepared. Size of powder particle prepared is uniform, and average particle size is 1-2μm.