以常見的高分子3D列印技術—DLP立體光刻技術成型⍺-氧化鋁陶瓷生胚。將陶瓷粉加入感光樹脂中，以光固化的方式聚合漿料中的感光樹脂，則可不經機械加工及開模就生產出形狀複雜的陶瓷器件。以次微米級或奈米級陶瓷粉末作為原料，可將燒結體的晶粒控制在微米級尺寸，建立未來製作形狀複雜之透光或透明氧化鋁陶瓷的基礎。然而相較於微米級陶瓷原粉，以平均粒徑為次微米級的起始粉末進行DLP成型陶瓷體，需要克服非水系感光樹脂中分散不易和列印過程中收縮率大的問題，這些都會造成列印後成品中產生缺陷。
本研究以平均粒徑180 nm之⍺-氧化鋁粉末分散於感光樹脂中，配製出固含量達40 vol%漿料，在剪切速率1 s-1和30 s-1時黏度分別低於1.5 Pa.s和0.5 Pa.s。接著比較兩種感光樹脂系統列印後成品脫脂後缺陷的差異，以探討固化過程中垂直裂紋和水平層裂等缺陷的成因。藉由調整感光樹脂種類、添加可塑劑控制玻璃轉換溫度，來解決生胚中的缺陷。研究結果顯示添加可塑劑至黏結劑與可塑劑比例為8:2時，可有效解決垂直裂紋與水平層裂。在含有寡聚物且玻璃轉換溫度高於室溫的系統中，氧化鋁胚體燒結後密度可達94%且平均抗彎強度達340 MPa。而在感光樹脂由單體組成的溶劑系統中，玻璃轉換溫度低於室溫，透過冷均壓2 MPa可以完全去除水平疊層方向的層裂，燒結後密度93%，抗彎強度90 MPa。

The main defects of fabricating high-performance alumina ceramic by using DLP 3D printing are the delamination resulting from the shrinkage during polymerization and porosity in the green body after organic binder burning out. A green body prepared by using a dispersed slurry with higher solid loading exhibits a homogeneous green microstructure with lower porosity and hence a dense sintered body with smaller grains being easily obtained. Moreover, the sinterability of the ceramic material increases with decreasing particle size. However, increasing the solid loading of slurry easily leads to particle agglomeration and hence increasing the viscosity and decreasing the particle size will lead to greater shrinkage during polymerization.
In this study, a dispersed alumina (particle size of about 180 nm) slurry with solid loading of 40 vol% was prepared as the raw material of DLP 3D printing. The effects of the photocurable resin systems and different amounts of plasticizer, PEG400, on the green microstructure, sintered density and mechanical strength were investigated. It was observed that the optimal resin composition is made up of monomer HDDA and oligomer EA at the ratio of 4:1. For the slurry with Binder/Plasticizer of 8:2, the defects in the sintered body can be fully eliminated and the sintered density and the average flexural strength can reach 94% and 340 MPa, respectively.

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