以燒結法製作毛細多孔結構之研究

The Investigation of Capillary Wick Structure Fabricated by Sintering Method

易星傑(Hsing-Chieh Yi)

指導教授 ： 邱六合

大同大學/工程學院/材料工程學系所/碩士(2004年)

摘要

本論文之目的在於分析銅粉特性(形狀、粒徑、粒徑分佈)和製程參數(燒結溫度與時間)對燒結多孔體的體積收縮率、孔隙率與滲透率的影響。使用三種製造方式—氣霧法(球形)、水霧法(不規則狀)和氧化還原法(多角形)及四種粒徑分佈(-149/+74, -149, -104, and -74 μm)的銅粉進行鬆裝燒結。結果顯示，隨著燒結溫度與燒結時間的增加，燒結體的體積收縮率上升，而孔隙率與滲透率是下降的。在相同粒徑下，使用不規則的銅粉會有較大的體積收縮率和孔隙率，但滲透率是較低的。在相同形狀下，使用較大粒徑的粉體可得較低之體積收縮率和較高之孔隙率和滲透率。使用氣霧法之燒結體具有低於5%的微量體積收縮率，和最高之滲透率(5×10-12 m2)。而使用–149 μm的水霧銅粉經過900℃燒結並持溫7200秒之燒結體具有最低的滲透率(1.1×10-13 m2)，除此之外，當燒結時間從1800秒增加至7200秒，滲透率會下降達一個order，這是因為小顆粒填補大孔洞造成之影響。因此，粒徑分佈對燒結多孔體的特性而言，是一項重要的參數。

關鍵字

燒結多孔體，孔隙率，滲透率

並列摘要

The purpose of this study is to analyze the effects of characteristics of copper powder (particle shape, particle size, and particle size distribution) and processing parameters (sintering temperature and sintering time) on the volume shrinkage, porosity, and permeability of sintered wick, respectively. Three fabricating methods, (1) gas atomization (spherical), (2) water atomization (irregular), and (3) oxide reduction (angular), and four classifications of particle size distribution─ -149/+74, -149, -104, and -74 μm of copper powders were used in loose pack sintering. The results show that, the volume shrinkage was increased but the porosity and permeability were decreased of the sintered wick with increasing sintering temperature and sintering time. In the same particle size, the sintered wick using the irregular particle got higher volume shrinkage and porosity but lower permeability. In the same particle shape, the sintered wick using larger particle got lower volume shrinkage, higher porosity and permeability. The sintered wick using gas atomized powder only got a small amount of volume shrinkage less than 5% and the highest permeability (5×10-12 m2) after sintering process. The water atomized powder with particle size distribution of –149 μm got the lowest permeability (1.1×10-13 m2) after sintering at 900℃ and holding 7200 s. Beside that, the value of permeability was decreased one order with increasing sintering time from 1800 s to 7200 s because the effect of the coarse pores filled up with fine particles. Therefore, the particle size distribution is an important parameter on the properties of sintered wick.

並列關鍵字

permeability ； porosity ； sintered wick

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