Gas Pressure Sintering of Arbitrary Porous Silicon Nitride Ceramics with High Mechanical Strength
Abstract:Gas pressure sintering is applied to prepare arbitrary porous silicon nitride (Si3N4) ceramics using yttria (Y2O3) as the sintering additive and naphthalene powder as the pore-forming agent. The results obtained show that the porosity of the sintered porous Si3N4 ceramics is 40%–54% when the Y2O3 content is from 3 to 15 wt% and the sintering temperature is from 1700° to 1850°C. The bending strength is in the range of 60–226 MPa. The porosity of the porous Si3N4 ceramics with Y2O3 content of 9 wt%, sintered at 1800°C, is increased to 51%–66% when the naphthalene powder content is 5–30 wt%. Finally, large and arbitrary porous Si3N4 ceramics with a porosity of ∼60% can be successfully fabricated by this method.
Document Type: Research Article
Affiliations: 1: Key Laboratory of Advanced Technology for Specially Functional Materials, Ministry of Education, Wuhan University of Technology, Wuhan 430070, China 2: Shandong Research and Design Institute of Industrial Ceramics, Zibo 255031, China 3: State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070, China
Publication date: 2010-06-01