The Positive Temperature Coefficient of Resistivity Effect in the Pb(Fe1=2Nb1=2)O3 Ceramics Admixed with Lithium

In the paper technological conditions were looked for to obtain the Pb(Fe1=2Nb1=2)O3 (PFN) ceramics and the PFN ceramics with the lithium admixture with the highest electric conduction and conditions appropriate for the PTC-R effect formation. Measurements of dc electrical resistivity, dielectric permittivity and dielectric loss were made as functions of temperature from room temperature to 190±C, at 1 kHz. The best set of values of dielectric loss and dielectric constant, from the ferroelectricity point of view, were obtained when the precursor with orthorhombic structure was employed. By creating appropriate technological conditions in the PFN ceramics the PTC-R effect can occur above the Curie temperature. Their electric properties are determined by presence of a basic phase of the potential barrier on the grain boundaries

Application of mechanical activation in synthesizing multiferroic Pb(Fe1/2Nb1/2)O3 powders

In the study, the method of high-energy powder milling – mechanical activation (MA) was used for synthesizing Pb(Fe1/2Nb1/2)O3 (PFN) powders. For the purpose of comparing the influence of high-energy milling on PFN synthesis, two groups of powder samples were used. The first mixture consisting of simple oxide powders; the second one consisting of compound oxide powders. The obtained powders were subjected to structural analysis with the use of XRD and Mossbauer spectroscopy. Tests revealed that during the process of high-energy milling of initial constituents a partial synthesis of PFN material phases occurs. By comparing the two methods of PFN synthesizing it may be stated that mechanical activation in the case of a simple oxide mixture (PFN1) is equally effective as for a compound oxide mixture (PFN2).[1] Y. X u, Ferroelectric materials and their applications. North – Holland, Amsterdam 1991. [2] S.L. S w a r t z, V.E. W o o d, Condensed Matter News 1, 4-14 (1992)[3] E.G. F e s e n k o, A.Ya. D a n c i g e r, O.N. R a z u -m o v s k a y a, Novye piezokeramicheskie materialy, RGU, Rostov-na-Donu, 1983. [4] O. R a y m o n d, R. F o n t, N. S u a r e z, J. P o r -t a l l e s, J. M. S i q u e i r o s, Ferroelectrics 294, 141 (2003). [5] K. S i n g h, S.A. B a n d, W.K. K i n g e, Ferroelectrics 306, 179 (2004). [6] X. G a o, J. X u e, J. W a n g, Journal of the American Ceramic Society 85, 565 (2002). [7] D. B o c h e n e k, Z. S u r o w i a k, Journal of Alloys and Compounds 480, 732-736 (2009). [8] D. B o c h e n e k, J. D u d e k, The European Physical Journal – Special Topics 154, 1 19-22 (2008). [9] D. B o c h e n e k, R. Z a c h a r i a s z, Archives of Metallurgy and Materials, 54, 903-910 (2009). [10] D. B o c h e n e k, Journal of Alloys and Compounds 504, 508-513 (2010). [11] B.D. S t o j a n o v i c, A.Z. S i m o e s, C.O. P a i -v a - S a n t o s, C. J o v a l e k i c, V.V. M i t i c, J.A. V a r e l a, Journal of the European Ceramic Society 25, 1985-1989 (2005). [12] J.S. B e n j a m i n, Scientific American 234, 40-43 (1976). [13] A.S. K h i m, X. J u n m i n, J. W a n g, Journal of Alloys and Compounds 343, 156-163 (2002). [14] X.S. G a o, J.M. X u e, T. Y u, Z.X. S h e n, J. W a n g, Materials Chemistry and Physics 75, 211-215 (2002). [15] J. W a n g, D.M. W a n, J.M. X u e, W.B. N g, Singapore Patent 9801566-2, 1998. [16] J. W a n g, D.M. W a n, J.M. X u e, W.B. N g, Journal of the American Ceramic Society 82, 477 (1999). [17] D. D e r c z, J. D e r c z, K. P r u s i k, A. H a n c, L. P a j ą k, J. I l c z u k, Archives of Metallurgy and Materials, 54, 741-745 (2009). [18] L.B. K o n g, J. M a, H.T. H u a n g, W. Z h u, O.K. T a n, Materials Letters 50, 129-133 (2001). [19] D. B o c h e n e k, Z. S u r o w i a k, J. K r o k - K o w a l -s k i, J. P o l t i e r o v a - V e j p r a v o v a, Journal of Electroceramics 25, 122-129 (2010). [20] Y. Y a n g, H.B. H u a n g, J.-M. L i u, Z.G. L i u, Ferroelectrics 280, 75-82 (2002)

Technology and properties ferroelectromagnetics lead-free BFN-ferrite composites

A lead free ceramic composite 0.9BaFe0:5Nb0:5O3-0.1Ni0:5Zn0:5Fe2O4 (BFN-NZF) with ferroelectromagnetic properties have been obtained in presented work. Ceramic composite powder obtained from the simple oxides Fe2O3, Nb2O5, ZnO, NiO and barium carbonate BaCO3. The composition of the composite was chosen so that the ratio of the BFN and NZF components was 90:10. The synthesis of components of BFN-NZF composite was performed using the calcination method. Final densification of synthesized powder has been done using free sintering. The XRD, the microstructure, EDS and dielectric investigations were performed. For comparison of the BFN ceramic and the BFN-NZF composites, temperature and frequency impedance research was conducted. Relaxation phenomena were observed at temperatures above 235 C in the BFN ceramic and above 150 C in the BFN-NZF composite. Obtained results show the coexistence of ferroelectric and magnetic properties. Such properties of obtained composites give the possibility to use them in magnetoelectric transducers.[1] D. K h o m s k i i, Physics 2, 20 (2009). [2] D. B o c h e n e k, Z. S u r o w i a k, Phys. Status Solidi A 206, 12, 2857-2865 (2009). [3] D. B o c h e n e k, P. G u z d e k, J. Magn. Magn. Mater. 323, 369-374 (2011). [4] Z. S u r o w i a k, D. B o c h e n e k, Arch. Acoust. 33, 2, 243-260 (2008). [5] J.F. S c o t t, J. Mater. Chem. 22, 4567-4574 (2012). [6] K.F. W a n g, J.-M. L i u, Z.F. R e n c, Adv. Phys. 58, 4, 321-448 (2009). [7] R. S i t k o, B. Z a w i s z a, J. J u r c z y k, D. B o c h e n e k, M. P ł o ń s k a, Microchim. Acta 144, 9-15 (2004). [8] C. K r u e a - I n, S. E i t s s a y e a m, K. P e n g p a t, G. R u -j i j a n a g u l, Mater. Res. Bull. 47, 2859-2862 (2012). [9] J.A. B a r t k o w s k a, J. I l c z u k, Int. J. Thermophys. 31,1-7 (2010). [10] N.K. S i n g h, P. K u m a r, R. R a i, J. Alloys Compd. 509,2957-2963 (2011). [11] K. Ć w i k i e l, E. N o g a s - Ć w i k i e l, Phase Transit. 80,1-2, 141-146 (2007). [12] D. B o c h e n e k, Z. S u r o w i a k, J. P o l t i e r o v a - V e -j p r a v o v a, J. Alloys Compds. 487, 572-576 (2009). [13] S. S a h a, T.P. S i n h a, J. Phys.: Condens. Matter 14, 249-258 (2002). [14] K. W ó j c i k, K. Z i e l e n i e c, M. M u l a t a, Ferroelectrics 289, 107-120 (2003). [15] S. E i t s s a y e a m, U. I n t a t h a, K. P e n g p a t, T. T u n k a s i r i, Curr. Appl. Phys. 6, 316-318 (2006). [16] K. P r a b a k a r, S.P. M a l l i k a r j u n R a o, J. Alloys. Compd. 437, 302-310 (2007). [17] H. Z h a n g, M. C h e e - L e u n g, J. Alloys Compd. 513, 165-171 (2012). [18] D. B o c h e n e k, P. N i e m i e c, A. C h r o b a k, G. Z i ó ł k o w s k i, A. B ł a c h o w s k i, Mater. Charact. (2013), doi: 10.1016/j.matchar.2013.10.027 [19] I.S. Y a h i a, M. F a d e l, G.B. S a k r, S.S. S h e n o u d a, F. Y a k u p h a n o g l u, W.A. F a r o o q, Acta Phys. Pol. A 120, 3, 563-566 (2011)

Characterization of energy conversion of multiferroic PFN and PFN:Mn

Characterization of energy conversion of multiferroic materials is concerned with multifunctional properties of materials, a topic that is fascinating from the scientific point of view and important for the modern technology. The complex characterization of multiferroic structures suffers at present from lack of a systematic experimental approach and deficiency of multifunctional magnetoelectric properties testing capabilities. Compactness and high frequency energy conversion capacity are the main reasons of invention and improvement of sophisticated materials which are prepared for high-speed computer memories and broadband transducer devices. As a consequence, one can easily notice an intense search for new materials for generation, transformation and amplification of magnetic and electric energies. In this scenario, the combination of excellent piezoelectric and magnetic properties makes lead iron niobate Pb(Fe1/2Nb1/2)O3 (PFN) an attractive host material for application in integrated magnetoelectric energy conversion applications. PFN multiferroic materials are attractive for commercial electroceramics due to high value of dielectric permittivity and magnetoelectric coefficients as well as relatively easy synthesis process. However, synthesis of PFN ceramics is mostly connected with formation of the secondary unwanted pyrochlore phase associated with dramatic decrease of ferroelectric properties. The authors have successfully reduced this negative phenomenon by Mn doping and finally present high piezoelectric and magnetoelectric energy conversion efficiency in fabricated PMFN ceramics

PbFe1/2Nb1/2O3 ceramics as a base material for electromechanical transducers

PbFe1=2Nb1=2O3 (PFN) material of perovskite structure has been rising interest because it connects both ferroelectric and antiferromagnetic properties. The paper presents tests of PFN ceramics obtained as a result of sintering simple oxides. As comparison, the base composition of the ceramics and composition with lithium admixture was synthesized. Densi cation was carried out using two methods: conventional sintering and hot pressing. XRD patterns, SEM micrographs of fractures surfaces, dielectric and electromechanical properties were performed. Admixing of PFN ceramics with a little amount of lithium allowed obtaining ceramics with better set of parameters from the point of view of their practical usage. The method of densi cation by hot pressing additionally improves these properties

Multiferroic materials for sensors, transducers and memory devices

Chemical compositions and basic properties of smart materials (ferroics, biferroics, multiferroics) are introduced in this paper. Single phase and composite ferroelectromagnetics are characterized in detail. Multiferroic ferroelectromagnetics are materials which are both ferromagnetic/ferrimagnetic/antiferromagnetic and ferroelectric/ferrielectric, antiferrolectric in the same phase. As a result they have a spontaneous magnetization which can be switched by an applied magnetic field, a spontaneous polarization which can be switched by an applied electric field, and often there is some coupling between those fields. The physical mechanisms of the coupling process were analyzed. In the case of the ferroelectromagnetics in general the transitions method d electrons, which are essential for magnetism, reduce the tendency for off-center ferroelectric distortion. Such materials have all the potential applications of both their parent ferroelectric and ferromagnetic materials

Microstructure and physical properties of the multicomponent PZT-type ceramics doped by calcium, sodium, bismuth and cadmium

In this work, the multicomponent Pb(Zr0.58Ti0.42)O3 ceramics doped by calcium (Ca), sodium (Na), bismuth (Bi) and cadmium (Cd) was designed and obtained by the hot uniaxial pressing method. Comprehensive electrophysical properties including crystalline structure, microstructure, dielectric, electromechanical and piezoelectric of the ceramics were made. The Pb0.92Ca0.02Na0.01Bi0.05(Zr0.58Ti0.42)0.98Cd0.02O3 ceramics obtained by the hot uniaxial pressing method has a microstructure of a regularly crystallized grain. The multicomponent material shows high values of dielectric and piezoelectric properties with high ferroelectric hardness. A wide and rectangular hysteresis loop of the PZT-type ceramics shows high ferroelectric hardness of obtained ceramics. Studies have also shown that multicomponent PZT-type ceramics exhibits a strong S–E behavior. The S–Eelectromechanical loops have characteristic “butterfly wings” shape with high values of mechanical strain. These properties of the obtained material allow its application in the modern microelectronics and micromechatronics, for example, in constructing electromechanical and electroacoustic transducers, piezotransformators, piezoelectric motors, etc.1. M. Venkata Ramana, S. Roopas Kiran, N. Ramamanohar Reddy, K.V. Siva Kumar, V.R.K. Murthy, B.S. Murty, Mater. Chem. Phys. 126, 295 (2011) 2. H. Schmid, J. Phys. Condens. Matter 20, 434201 (2008) 3. J. Kulawik, D. Szwagierczak, B. Gröger, Bull. Pol. Acad. Tech. 55, 293 (2007) 4. Z. Surowiak, D. Bochenek, Arch. Acoust. 33, 243 (2008) 5. R. Sitko, B. Zawisza, J. Jurczyk, D. Bochenek, M. Płońska, Microchim. Acta 144, 9 (2004) 6. K. Uchino, J.R. Giniewicz, Micromechatronics(Marcel Dekker, Inc., New York, 2003), pp. 103–265 7. H.S. Tzou, H.-J. Lee, S.M. Arnold, Mech. Adv. Mater. Struct. 11, 367 (2004) 8. W. Jo, R. Dittmer, M. Acosta, J. Zang, C. Groh, E. Sapper, K. Wang, J. Rödel, J. Electroceram. 29, 71 (2012) 9. S.-Y. Chu, T.-Y. Chen, I.-Ta Tsai, Walter Water Sens.Actuators A 113, 198 (2004) 10. S.L. Fu, S.Y. Cheng, C.C. Wei, Ferroelectrics 67, 93 (1986) 11. J. Deng, W. Zhu, O.K. Tan, X. Yao, Sens. Actuators B 77, 416 (2001) 12. E. Flint, C. Liang, C.A. Rogers, J. Intell. Mater. Syst. 6, 117 (1995) 13. F.P. Sun, Z. Chandhry, C. Liang, C.A. Rogers, J. Intell. Mater. Syst. 6, 134 (1995) 14. Q. Tan, D. Viehland, J. Am. Ceram. Soc. 81, 328 (1998) 15. K. Onitsuka, A. Dogan, J.F. Tressler, Q. Xu, S. Yoshikawa, R.E. Newnham, J. Intell. Mater. Syst. 6, 447 (1995) 16. Y. Xu, Ferroelectric Materials and Their Applications (Elsevier, Amsterdam, 1991), pp. 104–112 17. B. Noheda, D.E. Cox, G. Shirane, J.A. Gonzalo, L.E. Cross, S.-E. Park, Appl. Phys. Lett. 74, 2059 (1999) 18. B. Noheda, J.A. Gonzalo, L.E. Cross, R. Guo, S.-E. Park, D.E. Cox et al., Phys. Rev. B 61, 8687 (2000) 19. C. Bedoya, Ch Muller, J.-L. Baudour, V. Madigou, M. Anne, M. Roubin, Mater. Sci. Eng. B 75, 43 (2000) 20. B. Jaffe, R.S. Roth, S. Marzullo, J. Res. Natl. Bur. Stand. 55, 239 (1955) 21. M.R. Soares, A.M.R. Senos, P.Q. Mantas, J. Eur. Ceram. Soc. 20, 321 (2000) 22. A. Bouzid, E.M. Bourim, M. Gabbay, G. Fantozzi, J. Eur. Ceram. Soc. 25, 3213 (2005) 23. S.K. Mishra, A.P. Singhi, D. Pandey, Philos. Mag. 76, 213 (1997) 24. R.F. Zhang, H.P. Zhang, J. Ma, Y.Z. Chen, T.S. Zhang, Solid State Ionics 166, 219 (2004) 25. D. Bochenek, P. Niemiec, M. Adamczyk, Z. Machnik, G. Dercz, Eur. Phys. J. B 88, 279 (2015) 26. R. Zachariasz, D. Bochenek, Eur. Phys. J. B 88, 296 (2015) 27. P. Niemiec, R. Skulski, D. Bochenek, P. Wawrzała, Phase Transit. 86, 267 (2013) 28. R. Zachariasz, J. Ilczuk, D. Bochenek, Solid State Phenom. 89, 303 (2003) 29. D. Bochenek, R. Zachariasz, Phase Transit. 88, 799 (2015) 30. K.R.M. Rao, A.V.P. Rao, S. Komarneni, Mater. Lett. 28, 463 (1996) 31. R.F. Zhang, J. Ma, L.B. Kong, Y.Z. Chen, T.S. Zhang, Mater. Lett. 55, 388 (2002) 32. H. Hirashima, E. Onishi, M. Nakagowa, J. Non-Cryst. Solids 121, 404 (1990) 33. T.R.N. Kutty, R. Balachandan, Mater. Res. Bull. 19, 1479 (1984) 34. L.B. Kong, J. Ma, H.T. Huang, W. Zhu, O.K. Tan, Mater. Lett. 50, 129 (2001) 35. A.S. Karapuzha, N.K. James, H. Khanbareh, S. van der Zwaag, W.A. Groen, Ferroelectrics 504, 160 (2016) 36. O. Raymond, R. Font, N. Suárez-Almodovar, J. Portelles, J.M. Siqueiros, J. Appl. Phys. 97, 084107 (2005) 37. L.M. Hrib, O.F. Caltun, J. Alloy. Compd. 509, 6644 (2011) 38. L.B. Kong, J. Ma, Mater. Lett. 51, 95 (2001) 39. X. Yang, J. Zhou, S. Zhang, J. Shen, J. Tian, W. Chen, Q. Zhang, Ceram. Int. 41, 1657 (2015

Modified PZT ceramics as a material that can be used in micromechatronics

Results on investigations of the PZT type ceramics with the following chemical composition: Pb0.94Sr0.06(Zr0.50 Ti0.50)0.99 Cr0.01O3 (PSZTC) which belongs to a group of multicomponent ceramic materials obtained on basis of the PZT type solid solution, are presented in this work. Ceramics PSZTC was obtained by a free sintering method under the following conditions: T sint = 1250 °C and t sint = 2 h. Ceramic compacts of specimens for the sintering process were made from the ceramic mass consisting of a mixture of the synthesized PSZTC powder and 3% polyvinyl alcohol while wet. The PSZTC ceramic specimens were subjected to poling by two methods: low temperature and high temperature. On the basis of the examinations made it has been found that the ceramics obtained belongs to ferroelectric-hard materials and that is why it may be used to build resonators, filters and ultrasonic transducers

Dielectric properties of the PFN ceramics obtained different chemical-wet technology and sintering by hot pressing method

The paper shows three kinds of chemical-wet technology synthesis of the ferroelectric-ferrimagnetic PbFe1/2Nb1/2O3 materials and technology process of the ceramic samples sintered by hot pressing method. In the technological process of the PFN powders were used follows precursors: lead acetate trihydrate and niobium ethoxide while an iron-related components were changed: iron nitrate obtained by first sol-gel technology (PFN-n), iron oxalate obtained by second sol-gel technology (PFN-ox) and iron citrate obtained by third technology (PFN-c). XRD, SEM tests and temperature measurements of dielectric properties of the ceramic samples were carried out. The SEM microstructure tests of the PFN ceramic samples confirm the properly conducted technological processes. The best dielectric properties of the PFN ceramic samples were obtained for third technology using iron citrate precursor. But, this method of the PFN ceramic powder requires minimization of a pyrochlore phase and reduction porosity of the ceramic samples

An Influence of the Synthesis Conditions on the PFN Ceramics Properties

In the work tests of the influence of the technological conditions on the basic applied properties of the Pb(Fe0:5Nb0:5)O3 ceramics were carried out. The Pb(Fe0:5Nb0:5)O3 specimens were obtained by a two-stage method of synthesizing (the niobite method), a technique of the powder mixture calcinations, changing a temperature range of the iron-niobate (FeNbO4), whereas compacting was conducted by free sintering