Preparation and Thermal Expansion of Mullite-β-Spodumene Composite

[出版社版]rights: 社団法人日本セラミックス協会 rights: 本文データは学協会の許諾に基づきCiNiiから複製したものである relation: IsVersionOf: http://ci.nii.ac.jp/naid/110002289100/The influence of production conditions of P-spodumene powder and firing temperature on the sintering and microstructure of mullite-β-spodumene composites has been investigated. The mullite-β-spodumene composites were prepared from a commercial mullite powder and the β-spodumene powder synthesized using the sol-gel process. The sintering of the composites proceeded at a relatively low temperature by liquid phase sintering and then the composites in a relative density more than 90% containing 20-90 wt% ofβ-spodumene were prepared at 1400℃. The firing temperature and composition of composites were affected by the microstructure of composites. When liquid phase was too much during sintering, some large pores of 5-10μm were formed in the microstructure of composite, and this situation caused the relative density to lower. The thermal expansion and contraction curve of composites showed an approximately reversible behavior in the process of heating and cooling. The curve of thermal expansion coefficient was nearly linear for the change of β-spodumene composition, though this curve was influenced by a small amount of a-Al_2O_3 in the composites