Abstract Si3N4 ceramic is difficultly fabricated by digital light processing (DLP) based stereolithography method, due to a large refractive index difference between Si3N4 powder and resin. In this paper, a surface oxidation approach of Si3N4 powder for improving cure depth is proposed. The results showed that, the amorphous SiO2 layer was uniformly attached onto the surface of Si3N4 powder by surface oxidation, and the absorbance of Si3N4 powder decreased as increasing oxidation degree. Moreover, the cure depth of the suspension significantly increased because of a smaller absorbance and a refractive index difference at the interface between oxidized Si3N4 powder and resin. At the exposure energy of 500 mJ/cm2, the cure depth of the raw Si3N4 powder was 34 µm. After oxidizing at 1150 °C and 1200 °C for 1 h, the cure depth effectively increased to 42 µm and 51 µm, respectively. Finally, the complex-shaped Si3N4 parts were successfully fabricated using surface-oxidized Si3N4 powder via DLP method.

中文翻译：

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基于数字光处理的立体光刻法制备表面氧化氮化硅粉末复杂形状的陶瓷零件

摘要 由于Si3N4 粉末与树脂之间存在较大的折射率差异，因此基于数字光处理(DLP) 的立体光刻方法难以制造Si3N4 陶瓷。在本文中，提出了一种提高固化深度的 Si3N4 粉末表面氧化方法。结果表明，非晶SiO2层通过表面氧化均匀附着在Si3N4粉末表面，Si3N4粉末的吸光度随着氧化程度的增加而降低。此外，由于在氧化的 Si3N4 粉末和树脂之间的界面处具有较小的吸光度和折射率差异，悬浮液的固化深度显着增加。在 500 mJ/cm2 的曝光能量下，Si3N4 原料粉末的固化深度为 34 µm。在1150℃和1200℃氧化1小时后，固化深度分别有效地增加到 42 µm 和 51 µm。最后，通过 DLP 方法使用表面氧化的 Si3N4 粉末成功制造了形状复杂的 Si3N4 零件。