Effects of Technique Parameters on Gelating Process of Cordierite Ceramics Derived from Sol-Microemulsion-Gel Method

Abstract:

Nano-Cordierite powders used for high frequency chip inductors (MLCIs) were prepared by the sol-emulsion-gel method. The samples derived from these powders could be sintered at 900°C to be cordierite ceramics having a low dielectric constant and dielectric loss (ε=3.18, tgδ=0.00011; 1GHz). Effects of precursor concentration, treating temperature, and [H2O]/[Si] ratio of this material were studied. The pseudo-ternary phase diagram of sol/TritonX-100/n-hexanol/cy- clohexane was constructed and the influences of each variable on the phase diagram were discussed. Results showed that the optimal precursor concentration, treating temperature, and [H2O]/[Si] ratio for qualifying the gelation of the material were 1.5 mol/L, 45°C, and 4, respectively. Results also showed that for qualifying cordierite powders, the use of TritonX-100 as a surfactant together with n-hexanol as a co-surfactant could dissolve more magnesium nitrate and aluminium nitrate, and obtain a wider W/O micro-emulsion region than when other reagents were used. The samples derived from this method can be co-fired with a silver electrode, an ideal dielectric material for high frequency MLCIs.

• Periodical: Key Engineering Materials (Volumes 512-515)
• Pages: 1119-1123
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.512-515.1119
• Online since: June 2012
• Authors: Shao Hong Wang, Hao Ran Lu, Zhao Xia Hou, Chang Lei Niu, Zhao Lu Xue, Hao Wang, Cai Wang
• Keywords: Cordierite Ceramics, Sol-Micromulsion-Gel Method, Technique Parameters

References

[1] Janković-Častvan, S. Lazarević, D. Tanasković, Phase transformation in cordierite gel synthesized by non-hydrolytic sol-gel route, Ceram. Int. 33(2007)1263-1268.

DOI: 10.1016/j.ceramint.2006.05.003

[2] P. Ghosh, S. Sadhu, T. Sen, Upconversion emission of BaTiO3:Er nanocrystals, Bull. Mater. Sci. 31(2008)461-465.

DOI: 10.1007/s12034-008-0072-7

[3] A.M. Menchi, A.N. Scian, Mechanism of cordierite formation obtained by the sol-gel technique, Mater. Lett. 59(2005)2664-2667.

DOI: 10.1016/j.matlet.2005.04.014

[4] E.M. Briscoe. Ceramic material-Some product design considerations, Mater. Design 7(1986) 38-43.

[5] S.Taktak, M.S. Baspinar, Wear and friction behaviour of alumina/mullite composite by sol-gel infiltration technique, Mater. Design 26(2005)459-464.

DOI: 10.1016/j.matdes.2004.07.012

[6] H.Q. Wang, R.Z. Zuo, X Ji, Effects of ball milling on microstructure and electrical properties of sol-gel derived (Bi0.5Na0.5)0.94Ba0.06TiO3 piezoelectric ceramics, Mater. Design. 31(2010)4403- 4407.

DOI: 10.1016/j.matdes.2010.04.041

[7] S.D. Ramamurthi, Z.K. Xu, D.A. Payne. Nanometer-Sized ZrO2 Particles Prepared by a Sol- Emulsion-Gel Method, Am. Ceram. Soc. 73(1990)2760-2763.

DOI: 10.1111/j.1151-2916.1990.tb06761.x

[8] M. Okuyama, T. Fukui, C. Sakurai, Effect of addition rate and pH of water on cordierite powder prepared by complex-alkoxide hydrolysis, J. Non-Cryst. Solids 144(1992)298-304.

DOI: 10.1016/s0022-3093(05)80413-2

[9] N.K. Chaudhury, R. Bhardwaj, B.M. Murari, Fluorescence spectroscopic study to characterize and monitor TEOS based sol-gel process for development of optical biosensors, Curr. Appl. Phys. 3 (2003)177-184.

DOI: 10.1016/s1567-1739(02)00197-9

[10] M.A. Einarsrud, E. Nilsen, Strengthening of water glass and colloidal sol based silica gels by aging in TEOS, J. Non-Cryst. Solids 226 (1998)122-128.

DOI: 10.1016/s0022-3093(98)00370-6