Research on the Sinterability of MgAl₂O₃/SiC Composites in Air Atmosphere

Abstract:

MgAl₂O₄-SiC composites were prepared by using MgAl₂O₄ and SiC powder as main starting materials, being pressed to cylindrical specimens of Φ30mm×30mm at 200 MPa and heated respectively at 1400°C and 1500°C for 3 hours in air atmosphere. The room temperature physical properties of sintered samples were tested according to related national standards. The phase compositions were analyzed by XRD. The microstructure of the fracture of the samples was observed by SEM. The results showed that MgAl₂O₄-SiC materials could sintered well in air atmosphere. The mechanism is that SiC was oxidized to form active SiO₂, which reacted with MgAl₂O₄ to produce liquid cordierite promoting the sintering of the materials. The sinterability of MgAl₂O₄-SiC materials was overall improved with increasing the sintering temperature. When the content of SiC of MgAl₂O₄-SiC materials was 10%, the cold crushing strength and bulk density of the samples reached maximums and apparent porosity reached a minimum; the content of SiC was more than 10%, the sinterability of samples deteriorated.

• Periodical: Advanced Materials Research (Volumes 399-401)
• Pages: 834-837
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.399-401.834
• Online since: November 2011
• Authors: Chun Hui Cao, Jun Cong Wei, Jian Kun Huang, Jun Bo Tu
• Keywords: Air Atmosphere, Cordierite, MgAl₂O₄-SiC, Sinterability

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