以Y２O３-Al２O３-SiO２系玻璃燒結碳化矽的研究

SINTERING OF α-SiC WITH Y２O３-Al２O３-SiO２ GLASS ADDITIVES

謝震宇(Chen-Yu Hsieh)

指導教授 ： 林永仁

大同大學/工程學院/材料工程學系所/碩士(2012年)

摘要

本實驗以非反應液相燒結法製造碳化矽複合材料。首先將碳化矽粉末與添加劑粉末混合，再以50MPa壓成圓盤狀生胚，之後以1200~15000C常壓燒結胚體，並比較碳化矽加入不同添加劑後之試片強度、密度之關係。結果發現添加Y2O3-Al2O3-SiO2、Y2O3-Al2O3-SiO2-CaO、市售Ca-Al-Si-O系玻璃之SiC試片皆無法使碳化矽有效的緻密化。另外用低熔點的市售Ca-Al-Si-O、Mg-B-Si-O系玻璃作為添加劑，以熱壓方式於7500C進行碳化矽燒結，探索低溫緻密化的可能，結果也不甚理想。
以常壓13750C燒結SiC+30vol%Y2O3-Al2O3-SiO2的試片具有最佳抗壓強度71MPa，試片體密度為1.9g/cm3。以熱壓7500C燒結添加30vol%Mg-B-Si-O的試片，具有抗壓強度26MPa，體密度為2.2 g/cm3。低溫熱壓之試片的體密度較常壓燒結之試片高，但強度較低。

關鍵字

助燒劑 ； 液相燒結 ； 碳化矽

並列摘要

Non-reactive liquid-phase sintering of SiC has been studied using different additives. Additives were wet ball milling with SiC powder, dry-pressing at 50MPa to form disc-shaped pellets, then were sintered at 1200~15000C for 4 hours. The results indicated SiC samples with Y2O3-Al2O3-SiO2 , Y2O3-Al2O3-SiO2-CaO , Ca-Al-Si-O glass additive did not show any densification after pressureless sintering. This experiment also used low melting point of Ca-Al-Si-O and Mg-B-Si-O glass as additives, and hot-pressed. The hot-pressed samples did not significantly densified either.
Results indicated pressureless sintering SiC+30vol% Y2O3-Al2O3-SiO2 had the highest compressive strength of 71MPa with bulk density 1.9 g/cm3.Hot-pressed SiC+30vol% Mg-B-Si-O glass had compressive strength of 26MPa and bulk density of 2.2 g/cm3.

並列關鍵字

sintering aids ； liquid phase sintering ； silicon carbide

參考文獻

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