Journal of the Korean institute of surface engineering (한국표면공학회지)
- Volume 29 Issue 1
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- Pages.45-59
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- 1996
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- 1225-8024(pISSN)
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- 2288-8403(eISSN)
Synthesis of Ultrafine Powders for Aluminum Nitride by DC Thermal Plasma
직류 열플라즈마를 이용한 질화알루미늄 초미세분말의 합성
Abstract
Ultrafine powders(UFPs) of aluminum nitride(AlN) have been synthesized by chemical reactions in the nitrogen atmosphere and the gaseous aluminum evaporated from Al powders in thermal plasmas produced by a DC plasma torch. A synthesis system consisting of a plasma torch, a finely-controllable powder feeder, a reaction chamber, and a quenching-collection chamber have been designed and manufactured, and a filter for gathering AlN UFPs produced by the quenching process subsequent to the synthesis is set up. The synthesis process is interpreted by numerical analyses of the plasma-particle interaction and the chemical equilibrium state, respectively, and a fully-saturated fractional factorial test is used to find the optimum process conditions. The degrees and ultrafineness of synthesis are evaluated by means of SEM, TEM, XRD, and ESCA analyses. AlN UFPs synthesized in the optimum process conditions have polygonal shapes of the size of 5-100 nm, and their purities differ depending on collecting positions and filter types, and the maximum purity obtained is 72 wt% at the filter.
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