ZHANG Qishuai, CHEN Hua, CHEN Shihao, ZHANG Lingjing, ZHANG Geng
(School of Mechanical and Electrical Engineering, Xi'an Technological University, Xi'an 710021, Shaanxi, China)

Abstract: Focusing on slurries with alumina powder as ceramic matrix and sodium silicate as binder, which was frozen using the rapid prototyping laser scanning solidification technology, aiming at addressing the foaming issue of sodium silicate after laser scanning, a transient heat transfer simulation model was established using COMSOL to optimize the laser scanning spacing and the thickness of the slurry. Meanwhile, fly ash and aluminium silicate fibers were added to control the viscosity and chemical characteristics of the slurry. When 0.35 mm scanning distance and 0.2 mm paving thickness were adopted, while 40wt.% fly ash and 5wt.% aluminium silicate fibers were added, the foam dimension was significantly reduced, with the average pore sizes of the foams to be decreased from 188.33 μm to 80.46 μm and 100.96 μm, so that the smoothness of the material layer was improved. The strength of the green body was increased, with compressive strength to be 30.1 MPa and 28.8 MPa, respectively.

Key words: laser scanning, foaming, fly ash, aluminium silicate fiber, aperture