本研究為求低成本、高效率生產速率之快速凝固粉末，模擬Pratt&Whitney公司開發RSR(Rapid Solidfication Rate)技術建立離心霧化設備，並尋求最佳的合金粉末製程參數。本研究分析不同參數合金粉末之粉末橫截面圖、粒徑分布、長短比、中間粒度以及粉末產率，以這些數據分析各參數對粉末的影響。
本研究首先為建立離心霧化設備。以共晶成分的鉛錫合金為生產原料，探討霧化現象、霧化盤轉速、過熱、冷卻氣體壓力、以及霧化盤形狀等參數對霧化粉末之影響。
本實驗第一部分探討不同的霧化盤轉速對粉末的影響。隨著霧化盤轉速的增加，鉛錫粉末粒度隨之下降，然而當轉速為7500rpm時，粉末粒度會比6000rpm還大，這是因為熔湯在霧化盤上滑動。本實驗第二部分探討氣壁的有無對粉末的影響，使用氣壁對未凝固液滴有冷卻作用且會造成二次霧化的產生，粉末粒度因而變小。本實驗第三部分探討過熱度的影響，一般而言，隨著過熱度的增加，粉末粒度會隨之減少，然而在250℃時，粉末粒度會明顯增加，此為熔湯的黏度隨過熱增加而減少，因此融湯在霧化盤上滑移之故。本實驗第四部份探討霧化盤形狀的影響，此實驗證明，杯狀霧化盤會比平板霧化盤有更好的霧化能力。

In order to obtain low cost, high production efficiency alloy powder, we try to establish a centrifugal atomization apparatus which simulate Rapid Solidfication Rate(RSR) apparatus that Pratt&Whitney build up and modify the parameter. In the investigation, the powder cross section, particle distribution, aspect ratio of different parameters’ alloy powder will be analyzed. According to these analyses, it can find out the effect of each parameter to alloy powder.
In the investigation, the first work is to establish the centrifugal atomization apparatus. The raw material is eutectic Pb-Sn(63Sn37Pb). The parameters include atomization phenomenon, disc speed, gas pressure, super heat, and atomizer shape.
In the first section, the powder size decreases with increasing the disc speed. However, when the disc speed is 7500rpm, the powder size is coarser, for that liquid metal slips on the atomizer.
In the second section, it’s to discuss the gas shield. The gas shield can cool the un-solidification droplet and let droplet second-atomization.
In the third section, it’s to discuss superheat. In general, powder size increases with increasing the superheat. Since the viscosity of the liquid metal decreases with increasing superheat in 250℃, the slippage occurs.
In the fourth section, it’s to discuss the atomizer, the cup atomizer can avoid the slippage.

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