基于光固化增材制造技术的陶瓷成形方法

Ceramic Forming Method Based on Sterolighography Additive Manufacturing

目的利用光固化增材制造技术成形复杂形状陶瓷零件。方法以光敏树脂和陶瓷粉体混合得到氧化铝和氧化硅陶瓷浆料,浆料固体含量体积分数均超过55%。采用基于数字光处理技术的光固化增材制造设备,设计了一种栅栏式刮刀,可实现打印过程中高固含量浆料的均匀涂层和搅拌。光源波长为405 nm,面光源像素尺寸为50μm,最小分层厚度为10μm。在5 mW/cm^2光强下分层曝光,分析在不同粉体的浆料固化性能,得到陶瓷坯体,经过脱脂烧结,完成陶瓷成形。结果氧化硅浆料的透光性明显强于氧化铝浆料,氧化铝浆料的临界曝光强度更容易引发固化反应,测试件最小壁厚为0.2 mm,最小可成形孔为0.1 mm,并对氧化铝齿轮、螺钉、镂空摆件及氧化硅陶瓷型芯等复杂结构的陶瓷零件进行了验证。结论基于光固化成形的增材制造可以实现高精度的复杂陶瓷零件成形,对拓展陶瓷成形方法具有重要意义。

The paper aims to form ceramic parts of complex shapes based on sterolighography additive manufacturing.Alumina and silica ceramic slurry were prepared by mixing photosensitive resin with ceramic powders.The solid content and the volume fraction of slurry all exceeded 50%.Sterolighography additive manufacturing equipment based on digital light processing technology was adopted and a kind of fence scraper was designed to achieve uniform coating and stirring of high solid content slurry.The wavelength of the light was 405 nm,the pixel size of the graphics was 50μm,and the minimum layered thickness was 10μm.Under the light intensity of 5 mW/cm^2,the ceramic green body was shaped in layers,and the ceramic parts were gotten after degreasing and sintering.The light transmittance of silica slurry was obviously higher than that of alumina slurry.The critical exposure intensity of alumina slurry was more likely to initiate curing reaction.For the green parts,the minimum wall thickness of the test piece was 0.2 mm,and the minimum formable hole was 0.1 mm.Then the fabrication of alumina gears,screws,ornaments and silica ceramic cores of complex structures has been verified.Additive manufacturing based on sterolighography can realize the formation of complex ceramic components with high precision,which is of great significance to the development of ceramic forming methods.