摘要
本研究主要以實驗方法探討基板衝擊對超微細金屬粉末噴霧製程之效應，在金屬噴霧中加入碟形、環形、圓筒、多孔基板及其組合，藉以討論基板衝擊對金屬粉末噴霧製程之影響。實驗所採用之金屬成分為錫鉛合金﹙錫63%，鉛37%﹚，其熔點為183℃。實驗條件金屬溫度﹙Tm﹚為350℃，氣體壓力﹙Pg﹚2 bar。實驗所採用之金屬成分為錫鉛合金﹙錫63%，鉛37%﹚，其熔點為183℃。實驗條件金屬溫度﹙Tm﹚為350℃，氣體壓力﹙Pg﹚2 bar。在未配置基板時， 金屬粉末平均粒徑﹙SMD﹚為9.28μm，金屬粉末體積百分比﹙V0-15﹚為41.82%。實驗結果顯示，在噴嘴下方配置碟型基板可大幅降SMD且隨著碟型基板外徑D的增加而遞減。SMD可降低至5.25μm，V0-15也可提升至69.07％。且金屬噴霧之SMD隨著碟形基板對金屬噴霧遮蔽率之降低而增加。在遮蔽率同為100％下，由於碟形基板與噴嘴出口的距離不同，金屬噴霧會有不同程度之固化，故會影響金屬噴霧之平均粒徑。若於噴嘴下方配置多孔基板，則隨著多孔基板孔徑dp之減小，對噴霧之遮蔽面積漸增，SMD隨之遞減至6.25μm。若於噴嘴下方配置圓筒基板， SMD隨著圓筒基板邊緣高度Hp的增加而遞減至4.26μm，V0-15比例則遞增至59.65％。若於噴嘴下方配置碟型基板與環型基板之組合，在碟型基板外徑D與環形基板內徑Din相同時，則SMD會隨著碟型與環型基板距離△H減小而由10.86μm遞減至5.58μm， V0-15則遞增達53.21％。當D小於Din時， SMD會隨著碟型與環型基板的距離△H減小而遞增，由6.52μm遞增至8.98μm，V0-15則遞增至49.65%。若於噴嘴下方配置多孔基板與圓筒基板之組合，則SMD隨著多孔與圓筒兩基板距離△H減小而遞減，由2.88μm遞減至2.43μm，V0-15則從69.85%遞增至71.1%。另外，分析金屬粉末之粒徑分佈，發現在基板衝擊效應下，金屬粉末之分佈範圍更窄，故知基板衝擊效應能有效達成金屬粉末粒徑細微化與分佈窄化之目的。

Abstract
This research program investigates the production of Ultra-fine Metallic Powder by Atomization with Impingement on Substrates. Different geometry substrates are placed and are rearranged and combined in the metallic spray. To probe into the production of Ultra-fine Metallic Powder by Atomization with Impingement on Substrates. The metal used in this research was Sn63%Pb37% alloy with melting point 183℃. The metal was heated to 350℃ under the pressure ranging from 2 to 3.8 bar. The SMD and V0-15 of the molten spray was 9.28μm and 41.82%, respectively, without substrates. It was found that SMD decreased to 5.25μm and V0-15 increased to 69.07% as the diameter of the disc-type substrate was increased. It was due to the increase of the blockage ratio of the substrates in the spray flow. The particle size was also dependent on the distance between substrate and atomizer under the blockage ratio of 100% due to the different solidification processes of the molten spray in the downstream. The SMD decreased to 6.25μm when the disc-type type substrate was replaced by the porous substrate. It was due to the decrease of the blockage ratio under porous substrate condition. Furthermore, SMD decreased to 4.26μm and V0-15 increased to 59.65% as the disc-type type substrate was replaced by the cylindrical substrate. SMD was decreased as the height of the cylindrical ring was increased. The combination of the disk-type and ring-type substrates also resulted in decrease of the particle size. When the outer diameter of the disk-type substrate equaled to the inner diameter of the ring-type substrate, the SMD decreased from 10.86μm to 5.58μm and V0-15 increased to 53.21% as the distance between disk-type and ring-type substrate decreased. On the other hand, when the outer diameter of the disk-type substrate was smaller than the inner diameter of the ring-type substrate, the SMD increased from 6.52μm to 8.98μm and V0-15 increased to 49.65% as the distance between the disk-type and ring-type substrate was decreased. Finally, by combination of the porous and cylindrical substrates, SMD decreased from 2.88μm to 2.43μm and V0-15 increased from 69.85% to 71.1% as the distance between porous and cylindrical substrates was decreased. The particle size distribution of the metal powder was more concentrated under impingement of different substrates. It is concluded that the impinging mechanism of the molten spray on the substrates is an effective technique to control the particle size and size distribution in the metal powder production.

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