本研究以實驗的方法探討金屬粉末霧化與氣動篩分製程的整合。首先探討金屬噴霧在基板衝擊效應下之霧化特性及粉末分佈情形，所探討之參數包括：基板與噴嘴之距離、金屬噴射與氣體霧化之壓差、金屬熔湯之溫度以及不同位置量測之結果。其次利用SiO2粉末探討氣動篩分機制，操作參數包括：主流道速度、側流道速度、側流道開口位置，最後整合金屬粉末霧化與氣動篩分機制。實驗結果顯示，金屬粉末平均粒徑在基板與噴嘴間距、壓差、金屬熔湯溫度的影響下，可分別產生6.2μm、5.89μm、4.94μm之微粒。結果亦顯示，氣動篩分裝置藉由主、側流道速度的變化與側流道位置變化可以將粉末進行分級。整合金屬粉末霧化與篩分製程實驗結果顯示，在PN2=4.0bar，PM=1.5bar，H=8mm，15° Substrate，TM=400℃，主流道速度為1m/s，側流道速度為14m/s時，側流道的金屬粉末平均粒徑為4.18μm、Dv90為20.25μm、V0-15為80.03%，顯示此製程可以同時完成金屬粉末霧化與分級之結果，值得加以推廣應用。

This research investigates the combination of the atomization and classification processes in the production of metal powder. The atomization process was performed with the twin-fluid atomizers. The classification process was performed by the impingement of the molten spray on the substrate as well as the aerodynamic effects in the duct of the powder collection device. The parameters of this study include the distance between the atomizer and substrate, pressure of atomization, temperature of melt and the positions of the powder collection device. Results show the mean particle size of the metal powder was lowered down to 6.2μm, 5.89μm and 4.94μm, respectively, under different substrate configurations. The particle size was further lowered down to 4.18μm under the conditions of atomization process as PN2 = 4.0bar, PM = 1.5bar, H = 8mm, TM = 400℃, and under the conditions of the powder collection device with the velocities of primary and secondary channel being 1m/s and 14m/s, respectively. It turns out that Dv90 can be lowered down to 20.25μm and most of the particles is within 15μm, i.e., V0-15 was up to 80.03%. It can be concluded that this technique can be used to produce extra-fine metal powders for various industrial applications.

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