陶瓷雷射燒結快速原型技術之強度提昇及生薄層塊去除研究

Mechanical Strength Elevating and Green Portion Removal in Rapid Prototyping Using Ceramics Laser Sintering

蘇紘建(Hung-Chien Su)

指導教授 ： 湯華興

國立臺北科技大學/機電學院/製造科技研究所/碩士(2008年)

https://doi.org/10.6841/NTUT.2008.00462

摘要

本研究之主要目的是提昇工件強度與發展黏結劑分別為黏土及聚乙烯醇之生薄層塊之去除方式。為達到此目的必須從製程源頭開始做改變，藉由改變漿料配方以及建立雷射掃描成型參數與後處理，使完成後的工件緻密度及強度提高；生薄層塊之去除方式將配合黏結劑之特性研發去除生薄層塊之方法。
本研究首先對漿料配方進行改良，漿料包括了主要氧化鋁陶瓷粉末及有機黏結劑此兩種主要配方，首度使用聚乙烯醇水性高分子有機黏結劑混合氧化鋁陶瓷粉末經球磨攪拌製成之陶瓷漿料（其中氧化鋁粉末之平均粒徑為0.5μm），針對漿料的配方、流變性質與均質性作探討，並調配出分散狀況良好之氧化鋁漿料。建立雷射掃描成型參數使之經由雷射選擇性掃描生薄層塊來成型工件，最終再藉由爐中600℃燒失黏結劑及1600℃高溫燒結來獲得平均相對密度達到93%與平均抗彎強度為232.5MPa之氧化鋁陶瓷工件。第二部分首先針對去除黏結劑為黏土之二氧化矽漿料所製作之中空工件提出使用水氣噴槍及夾治具搭配，可以不損壞中空工件且能有效的去除生薄層塊；再針對除黏結劑為聚乙烯醇但氧化鋁粉末表面性質不同之漿料所製作之生薄層塊進行製作流道與酸鹼溶液之生薄層塊去除實驗，最終找到將陶瓷生薄層塊置入過氧化氫溶液中並搭配超音波震盪的方式可有效的去除氧化鋁陶瓷生薄層塊。

關鍵字

陶瓷雷射燒結 ； 氧化鋁 ； 去除生薄層塊

並列摘要

The aim of this study is to improve the mechanical strength and to develop the methods of green portion removal for the slurry contained clay and PVA as binders. In order to achieve the goal, the modification has to be started from the very beginning. By changing the formulation of the slurry, establishing the laser scanning parameters, and executing a post-process, the density and mechanical strength of the alumina part can be elevated. The method of the green portion removal is adapted to the characteristics of each binder.
Firstly, the formulation of the slurry was modified. The slurry included alumina powder (the average particle size of alumina is 0.5μm) and organic polyvinyl alcohol binder. The formulation, rheological properties and the homogeneity of the slurry were investigated; a well-dispended alumina powder was obtained. The laser scanning parameters were built to fabricate ceramic part by selective scanning the thin layers. Alumina ceramic parts were obtained by burning out binder at 600℃ and sintering the green parts at 1600℃. Finally, the theoretical density of alumina ceramic parts was 93% and the average bending strength was 232.5MPa.
Secondly, removing green portion of a hollow part fabricated with the slurry contained silica powder and clay, using a nozzle and fixtures can effectively remove green portion without damaging the hollow part. The experiment of removing green portion was conducted for the slurry which contained PVA and alumina powders which have different surface properties. Eventually, the green portion can be effectively removed by immersing it in the H2O2 solution and vibrating with an ultrasonic vibrator for a period of time.

並列關鍵字

ceramic laser sintering ； alumina ； removal green portion

參考文獻

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