Back
 MSA  Vol.7 No.4 , April 2016
The Thermal Stability of (CaTiO3)1-x (Cr3/4Fe5/4O3)x Ceramic Composites in the Microwave Region
Abstract: The thermal stability, structural and dielectric properties of the (CaTiO3)1-x(Cr3/4Fe5/4O3)x ceramic composites with x = 0, 0.1, 0.5, 0.9 and 1 have been examined in microwave region. The samples were produced via the solid-state reaction. The orthorhombic structural phase of CaTiO3 and trigonal structural phase of Cr3/4Fe5/4O3 were confirmed by the X-Ray Powder Diffraction (XRPD). The XRPD patterns for composites reveal the quantities of each original phase present. The infrared spectra of the samples reinforce this structural verification indicating no or minimal occurrence of unwanted reactions. The first sample (x = 0) and last sample (x = 1) in this series exhibit the maximum and the minimum of the relative dielectric permittivity and values range from 140.1 to 8.3 respectively. The measured temperature coefficient of the matrix CaTiO3 was +921 ppm·-1 and for the matrix Cr3/4Fe5/4O3 was -56 ppm·-1. With the study of series of composites, it was possible to make a mathematical prediction for a composition reach the temperature coefficient near zero. The proposed ceramic has potential use as thermostable material in the microwave region and can be applied to resonators, low-noise amplifiers, filters, and so on.


Cite this paper: Aguiar Freire, F. , Pimentel Santos, M. , Barbosa Rocha, H. , Leite Almeida, A. , Mazzetto, S. , Mangueira Sales, A. and Bezerra Sombra, A. (2016) The Thermal Stability of (CaTiO3)1-x (Cr3/4Fe5/4O3)x Ceramic Composites in the Microwave Region. Materials Sciences and Applications, 7, 202-209. doi: 10.4236/msa.2016.74020.
References

[1]   Plourde, J.K. and Ren, C.-L. (1981) Application of Dielectric Resonators in Microwave Components. IEEE Transactions on Microwave Theory and Techniques, 29, 754-770. http://dx.doi.org/10.1109/tmtt.1981.1130444

[2]   Wersing, W. (1996) Microwave Ceramics for Resonators and Filters. Current Opinion in Solid State and Materials Science, 1, 715-731. http://dx.doi.org/10.1016/s1359-0286(96)80056-8

[3]   Reaney, I.M. and Iddles, D. (2006) Microwave Dielectric Ceramics for Resonators and Filters in Mobile Phone Networks. Journal of the American Ceramic Society, 89, 2063-2072. http://dx.doi.org/10.1111/j.1551-2916.2006.01025.x

[4]   Zhao, F., Yue, Z.X., Zhang, Y.C., Gui, Z.L. and Li, L.T. (2005) Microstructure and Microwave Dielectric Properties of Ca[Ti1-x(Mg1/3Nb2/3)x]O3 Ceramics. Journal of the European Ceramic Society, 25, 3347-3352. http://dx.doi.org/10.1016/j.jeurceramsoc.2004.07.036

[5]   Rocha, H.H.B., Freire, F.N.A., Costa, R.C.S., Sohn, R.S.T.M., Orjubin, G., Junqueira, C.C.M., Cordaro, T. and Sombra, A.S.B. (2007) Dielectric Resonator Antenna: Operation of the Magnetodielectric Composites Cr0.75Fe1.25O3 (CRFO)/Fe0.5Cu0.75Ti0.75O3 (FCTO). Microwave and Optical Technology Letters, 49, 409-413. http://dx.doi.org/10.1002/mop.22160

[6]   Rocha, H.H.B., Freire, F.N.A., Santos, M.R.P., Sasaki, J.M., Cordaro, T. and Sombra, A.S.B. (2008) Radio-Frequency (RF) Studies of the Magneto-Dielectric Composites:Cr0.75Fe1.25O3 (CRFO)-Fe0.5Cu0.75Ti0.75O3 (FCTO). Physica B: Condensed Matter, 403, 2902-2909. http://dx.doi.org/10.1016/j.physb.2008.02.033

[7]   Rocha, H.H.B., Freire, F.N.A., Silva, R.R., Gouveia, D.X., Sasaki, J.M., Santos, M.R.P., Goes, J.C. and Sombra, A.S.B. (2009) Structural Properties Study of the Magneto-Dielectric Composite: Cr0.75Fe1.25O3 (CRFO):Fe0.5Cu0.75Ti0.75O3 (FCTO). Journal of Alloys and Compounds, 481, 438-445. http://dx.doi.org/10.1016/j.jallcom.2009.03.002

[8]   Rocha, H.H.B., Freire, F.N.A., Sohn, R.S.T.M., Silva, M.G., Santos, M.R.P., Junqueira, C.C.M., Cordaro, T. and Sombra, A.S.B. (2008) Bandwidth Enhancement of Stacked Dielectric Resonator Antennas Excited by a Coaxial Probe: An Experimental and Numerical Investigation. IET Microwaves, Antennas & Propagation, 2, 580-587. http://dx.doi.org/10.1049/iet-map:20070292

[9]   Costa, R.C.S., Costa, A.B., Freire, F.N.A., Santos, M.R.P., Almeida, J.S., Sohn, R.S.T.M., Sasaki, J.M. and Sombra, A.S.B. (2009) Structural Properties of CaTi1-x(Nb2/3Li2/3)xO3-δ(CNLTO) and CaTi1-x(Nb1/2Ln1/2)xO3 (Ln=Fe (CNFTO), Bi (CNBTO)), Modified Dielectric Ceramics for Microwave Applications. Physica B: Condensed Matter, 404, 1409- 1414. http://dx.doi.org/10.1016/j.physb.2008.12.037

[10]   Rietveld, H.M. (1967) Line Profiles of Neutron Powder-Diffraction Peaks for Structure Refinement. Acta Crystallographica, 22, 151-152. http://dx.doi.org/10.1107/s0365110x67000234

[11]   Bleicher, L., Sasaki, J.M. and Santos, C.O.P. (2000) Development of a Graphical Interface for the Rietveld Refinement Program DBWS. Journal of Applied Crystallography, 33, 1189. http://dx.doi.org/10.1107/S0021889800005410

[12]   Young, R.A., Sakthivel, A., Moss, T.S. and Paiva-Santos, C.O. (1995) DBWS-9411—An Upgrade of the DBWS*.* Programs for Rietveld Refinement with PC and Mainframe Computers. Journal of Applied Crystallography, 28, 366- 367. http://dx.doi.org/10.1107/S0021889895002160

[13]   Hakki, B.W. and Coleman, P.D. (1960) A Dielectric Resonator Method of Measuring Inductive Capacities in the Millimeter Range. IRE Transactions on Microwave Theory and Techniques, 8, 402-410. http://dx.doi.org/10.1109/TMTT.1960.1124749

[14]   Courtney, W.E. (1970) Analysis and Evaluation of a Method of Measuring the Complex Permittivity and Permeability Microwave Insulators. IEEE Transactions on Microwave Theory and Techniques, 18, 476-485. http://dx.doi.org/10.1109/TMTT.1970.1127271

[15]   Kobayashi, Y. and Tanaka, S. (1980) Resonant Modes of a Dielectric Rod Resonator Short-Circuited at Both Ends by Parallel Conducting Plates. IEEE Transactions on Microwave Theory and Techniques, 28, 1077-1085. http://dx.doi.org/10.1109/TMTT.1980.1130228

[16]   Chen, L., Ong, C., Neo, C., Varadan, V. and Varadan, V. (2004) Microwave Electronics: Measurement and Materials Characterization. Wiley, New York. http://dx.doi.org/10.1002/0470020466

[17]   Castro, P.J. and Nono, M.C.A. (1999) Microwave Properties of Barium Nanotitanate Dielectric Resonators. Journal of Microwaves and Optoelectronics, 1, 12-19.

[18]   Belsky, A., Hellenbrandt, M., Karen, V.L. and Luksch, P. (2002) New Developments in the Inorganic Crystal Structure Database (ICSD): Accessibility in Support of Materials Research and Design. Acta Crystallographica, Section B: Structural Science, Crystal Engineering and Materials, 58, 364-369. http://dx.doi.org/10.1107/S0108768102006948

[19]   Chakhmouradian, A.R. and Mitchell, R.H. (1998) A Structural Study of the Perovskite Series CaTi1?2xFexNbxO3. Journal of Solid State Chemistry, 138, 272-277. http://dx.doi.org/10.1006/jssc.1998.7803

[20]   Durbin, J. and Watson, G.S. (1971) Testing for Serial Correlation in Least Squares Regression. III. Biometrika, 58, 1-19. http://dx.doi.org/10.2307/2334313

[21]   Kim, K.H., Uehara, M., Hess, C., Sharma, P.A. and Cheong, S.-W. (2000) Thermal and Electronic Transport Properties and Two-Phase Mixtures in La5/8?xPrxCa3/8MnO3. Physical Review Letters, 84, 2961-2964. http://dx.doi.org/10.1103/PhysRevLett.84.2961

[22]   Nakamoto, K. (1963) Infrared Spectra of Inorganic and Coordination Compounds. 4th Edition, Wiley, New York.

[23]   Jacob, K.S., Satheesh, R. and Ratheesh, R. (2009) Preparation and Microwave Characterization of BaNd2?xSmxTi4O12 (0≤x≤2) Ceramics and Their Effect on the Temperature Coefficient of Dielectric Constant in Polytetrafluoroethylene Composites. Materials Research Bulletin, 44, 2022-2026. http://dx.doi.org/10.1016/j.materresbull.2009.06.001

 
 
Top