Solid freeform fabrication of alumina ceramic parts through a lost mould method

A new rapid prototyping method is developed by combining SLS (selective laser sintering) and gelcasting technique for the fabrication of complex-shaped Al2O3 ceramic parts. Based on the specially selected composite plastic powders, SLS is utilized to fabricate sacrificial moulds for the ceramic parts. Aqueous gelcasting technique is utilized to form high mechanical strength Al2O3 green body by the in situ polymerization of high solids loading Al2O3 slurry containing monomer and cross-linker. Because of the high green strength of the Al2O3 parts, the desired geometry of the ceramic structure is successfully retained after sintering of the ceramics. Ceramic slurry composition and binder removal cycle development work for alumina ceramics are also described in detail in this paper.