Study on Laser Selective Curing Additive Manufacturing of Foamed Structural Ceramics

Abstract

An additive manufacturing method for ceramic materials with internally formed foaming structure was proposed in this paper with the adoption of ceramic powder and sodium silicate binder to prepare sizing agent. The forming process on each layer consists of three basic processes, including spreading, freezing and laser scanning. Foaming structure arises due to the foaming effect of the frozen sodium silicate caused by laser gasification. After 3D printing, the support material in frozen state will be removed when it has been melt in water. Then finally the green ceramic parts internally filled with foaming structures will come into being. Experimental results show that the laser parameters, the content of ceramic, the scanning spacing and other factors affect the interior appearance of the green part. At the scanning speed of 100 mm·s-1, laser power of 20 W, and 0.3 mm scanning spacing, the ceramic parts are processed with a slurry with 50% solid content. The support materials in the deep fine structure can be quickly removed without mechanical damage or swelling in the water. This new process can be used to process thermal insulation ceramic parts.