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The single Bi4-xEuxTi3O12 and Ni1-xCuxFe2O4 films were prepared via spin-coating method. The composite films of the Bi3.4Eu0.6Ti3O12/Ni0.7Cu0.3Fe2O4, annealed under N2, air and O2, were also prepared via the same method. Compared with the films of Bi4Ti3O12, the films of the Eu-doped Bi4Ti3O12 (Bi4-xEuxTi3O12) exhibit enhanced ferroelectricity. And when x is equal to 0.6, the films of Bi4-xEuxTi3O12 show optimal ferroelectricity. Compared with the undoped NiFe2O4 film, in the films of Ni1-xCuxFe2O4, the doping of Cu2+ enhances ferromagnetism. And when x is equal to 0.3, the Ni1-xCuxFe2O4 films exhibit optimal ferromagnetism. For the composite films of Bi3.4Eu0.6Ti3O12/Ni0.7Cu0.3Fe2O4, annealing atmosphere has a significant impact on the magnetoelectric properties. In comparison with the composite films annealed under N2 and air, the composite films annealed under O2 exhibit optimum ferroelectricity (saturation polarization being 26.3 μC·cm−2), ferromagnetism (saturation magnetization being 385.6 emu·cm−3) and enhanced magnetoelectric coupling effect (magnetoelectric voltage coefficient being 86.4 mV·(cm·Oe)−1). This is beneficial for the applications in magnetoelectric functional devices.

Bismuth ferrite (BiFeO3) is one of multiferroic material group, but it is difficult to produce BiFeO3 in single phase as multiferroic material because it occurs leakage of current arising from non stoichiometric. So, to minimize it, it has already been engineering processed to synthesis BiFeO3 doped by Mg to produce Bi0.9Mg0.1FeO3 and Bi0.93Mg0.07FeO3. It used sol-gel method to produce the ceramics. The result of TGA/DTA(Thermo Gravimetric Analysis/Differential Thermal Analysis) test shows that the temperature of calcination is about of 150 and 175oC and temperature of sintering is about of 650oC. Characterization of the powder has already been done by using X-Ray Diffraction (XRD) test and electrical properties test. The results of XRD test show that the powder of Bi0.9Mg0.1FeO3has minimum impurities with total oxide of 6.9% (bismite 3.5% and silenite 3.4%) at calcination temperature of 175oC for 4 hours and sintering at 650oC for 6 hours. Meanwhile at same parameter, Bi0.93Mg0.07FeO3 has more oxide phases with total oxide of 14.5% which consists of silenite (2.5%) and Bi2O4 (12%). Presence of oxide phases could cause leakage of current decreasing electrical properties. The values of electrical saturation polarization for ceramic having minimum total oxide (Bi0.9Mg0.1FeO3) is higher than ceramic having more oxide (Bi0.93Mg0.07FeO3). The value of electric saturation polarization for Bi0.9Mg0.1FeO3 is of 0.26 kv/cm and for Bi0.93Mg0.07FeO3 is of 0.11 kV/cm.

0.65Pb(Mg1/3Nb2/3)O3–0.35PbTiO3 (PMN–PT) thin films were deposited on (111)Pt/Ti/SiO2/Si substrates via the chemical solution deposition. Both of the annealing process and additive methanamide play an obvious part in the structure and electrical properties of PMN–PT films. The optimized high-qualitied PMN–PT thin film in present work is fabricated with the methanamide in the precursor and annealed at 650 °C for 20 min. The film exhibits pure perovskite phase and superior ferroelectricity. The saturation polarization Ps and remanent polarization Pr are 52.1 µC/cm2 and 18.7 µC/cm2 at 500 kV/cm with 1000 Hz. It also shows low leakage current density of approximately 1.0 × 10− 8 A/cm2 at 200 kV/cm.

Lead-free piezoelectric ceramics [(Ba 0.85 Ca 0.15 )(Ti 0.90 Zr 0.10 )O 3- xBiErO 3 (BCTZ-xBE)] doped with a new doping material BiErO 3 (BE) has been synthesized successfully via solid state reaction technique, and their structural, dielectric, ferroelectric, and piezoelectric properties have been investigated. A high dielectric constant with very low dielectric loss and high remnant polarization followed by a low coercive field has been obtained with the addition of x = 0.5 BE. Bulk ferroelectric hysteresis loops were obtained with a maximum polarization P max = 26.7 μC/cm 2 and a saturation polarization P s = 16.65 μC/cm 2 along with a coercive field of E c ≈ 2.45 kV/cm. Results demonstrate an induced-strain increasing from ~ 0.11 to ~ 0.24 for x = 0.5, excellent piezoelectricity with d 33 = 560 pC/N, k p = 56%, Q m = 196, e m = 11,200 and tan δ = 0.01.

The polyvinylidene fluoride (PVDF) thick film has been fabricated by a solution casting method. The fabricated film is subjected to annealing at 50, 90, 100, 110 and 130 °C for 5 h. The effect of annealing on structural, crystalline, dielectric and polarization behavior is investigated. The β-phase PVDF is found to coexist with α-phase for annealing temperature upto 100 °C, after that β-phase is converted to α-phase. The film annealed at 100 °C, exhibits enhanced permittivity, reduced tangent loss and enhanced polarization. The dielectric permittivity and tangent loss of film annealed at 100 °C are ~11 and ~0.025 respectively for the frequency range of 103–105 Hz. The saturation polarization for this film is ~1.27 µC/cm2. The enhanced dielectric permittivity and polarization for the film annealed at 100 °C might be attributed to increase in crystalline α and β-phase interface as well as crystalline amorphous interface. The thick film of PVDF with improved dielectric and polarization behavior could be useful for high power electronics application.

We previously reported a new compound for permanent magnets, (Nd0.7Zr0.3)(Fe0.75Co0.25)11.5Ti0.5N0.56, which has a high saturation polarization (Js) of 1.68 T and a high magnetocrystalline anisotropy field (Ha) of 2.88–4.0 MA/m. Here, we examined the effects of substituting Co and Ti at the Fe sites and Zr at the Nd sites. Js increased with Co substitution at the Fe sites, and higher Fe and Co content could be achieved by decreasing the Ti content to −Ti0.5. The ThMn12 structure with high Fe and Co content (i.e. low Ti content) was stabilized mainly by −Zr0.3 substitution at the Nd sites. The Zr substitution resolves the local mismatch in atomic size in the structure. Specifically, the atomic radius of Zr is about 88% that of Nd, so the local structure surrounding Nd (2a site) shrinks as a result of the substitution and resolves the size mismatch in the three types of local Fe six-fold symmetric hexagons in the structure. The effect of the α-(Fe, Co) phase on Js was evaluated from the phase's volume fraction measurement of 7.7% (8.1 wt%) by electron backscatter diffraction. Nitrogenation of the starting alloy also resulted in augmentation of the c-axis magnetocrystalline anisotropy. Finally, we confirmed a high Js(−N1.3) of 1.71T (=1.67 T, −0.04 T for the α-(Fe, Co) phase) and Ha of 2.9–5.25 MA/m (Ha(−N1.3)=5.25 MA/m) in the (Nd0.7Zr0.3)(Fe0.75Co0.25)11.5Ti0.5Nα (α=0.60–1.30) compounds.

It is shown that a substantial enhancement of the electrocaloric (EC) effect can be achieved with a properly engineered, ceramic microstructure. In particular, a significant impact of the grain size on the EC effect in 0.9Pb(Mg1/3Nb2/3)O3–0.1PbTiO3 ceramics is demonstrated. The single-phase perovskite ceramics with grain sizes ranging from 2.8 to 9.4 mm were prepared. The largest EC coefficient ΔTEC/ΔE is obtained for the ceramic with 5.8-μm grains, as a consequence of its larger saturation polarization. The EC response is limited by the breakdown strength of the material, which is higher than 160 kV cm−1 for the fine-grained ceramics. For the material with a ∼98% relative density and 3.6-μm grains, the large EC temperature change (ΔTEC) of 3.45 °C is achieved. This value is the highest reported so far for Pb-based perovskites and is comparable to best results obtained by multi-critical-point enhancement.

(100)- and (111)-oriented epitaxial Pb(Mg 1/3 Nb 2/3 )O 3 films with 500 and 1300 nm in thickness were grown by metal organic chemical vapor deposition. Remained strain was almost relaxed because the crystal structure of the films was almost the same as that of bulk Pb(Mg 1/3 Nb 2/3 )O 3 . Relative dielectric constant showed the maximum value against the temperature that depended on the measurement frequency. Maximum relative dielectric constant, e r (max.), and the temperature showing e r (max.), T (max.), decreased and increased with the frequency, respectively, are in good agreement with reported data for the bulk. e r (max.) and T (max.), respectively increased and decreased with the film thickness and (111)-oriented films showed larger value than that of the (100)-oriented one. Ferroelectricity was observed for all films up to 297 K and monotonously decreased with increasing temperature. Saturation polarization value increased with the film thickness and (111)-oriented films showed larger value than (100)-oriented ones. On the other hand, the coercive field decreased with increasing film thickness, but was almost independent with the film orientation.

Amorphous ribbons of composition Fe 85.2-x Co x Si 0.5 B 9.5 P 4 Cu 0.8 (x = 0 at% and 4 at%) have been flash annealed for 10 s at temperatures between 350 °C and 540 °C. Above about 400 °C a nanocrystalline state of bcc Fe(Co) is formed with a crystalline fraction of 50–55% and grain sizes of about 16–18 nm. The optimum nanocrystalline state reveals a saturation polarization up to J s =1.82 T–1.83 T and a coercivity as low as 3–5 A m −1 . The present paper complements the so far missing magnetostriction data for these alloys. Magnetostriction decreases from initially 40 ppm in the as cast amorphous state to about 14 ppm (x = 0 at%) and 19 ppm (x = 4 at%), respectively, after formation of the fully developed nanocrystalline state.

We applied Vopsaroiu's model to (Bi,Pr)(Fe,Mn)O3 (BPFM) and Pb(Zr,Ti)O3 (PZT) ferroelectric thin films fabricated by chemical solution deposition. The temperature dependences of the saturation polarization and the coercive field were measured in a low-temperature region from 100 to 200 K. The saturation polarizations of BPFM thin films decreased on decreasing the measurement temperature due to the polarization pinning effect, while that of PZT thin film was almost unchanged over the temperature region. The coercive fields of all the thin films were increased linearly on decreasing the measurement temperature. The activation energies for polarization reversal in as-grown BPFM, postannealed BPFM, and PZT thin films were 1.18, 1.25, and 0.95 eV, respectively. These results indicate that BPFM thin films have large activation energies for polarization reversal compared with PZT thin films. In addition, the postannealed BPFM thin film has a larger activation energy than the as-grown BPFM thin film.

The law of approach to ferromagnetic saturation (LAFS) method is required for the accurate measurement of the magnetic properties of magnetically isotropic materials. In this study, we examined the accuracy of the following two LAFS methods for determining the saturation polarization (Js) and anisotropy field (Ha) of isotropic magnets: (1) the method based on the relationship between polarization (J) and applied field (H; 1/H2); and (2) the method based on the relationship between susceptibility (dJ/dH) and 1/H3. We used an isotropic magnet prepared from a commercial ferrite magnet powder with well-known magnetic properties and low Ha as a standard magnet for evaluating the two LAFS methods. Then, we measured the Js and Ha values of our -Ti0.7 compounds with a ThMn12 structure, (Nd0.8Zr0.2)(Fe0.9Co0.1)11.3Ti0.7N1.5 and (Sm0.9Zr0.1)(Fe0.8Co0.2)11.3Ti0.7, including in the high-temperature region (>373 K), where the reduction of Ha was observed. Finding the adequate maximum magnetic fields, where the Js and Ha values obtained by the two LAFS methods agree well, is important for the proper application of the method to isotropic magnet samples. The results of the LAFS methods revealed that the Js values of the new compounds are similar at RT, but higher than that of the Nd2Fe14B phase in the high-temperature region. Because the -Ti0.7 compounds are almost α-(Fe,Co)-phase-free, their Ha values are also higher than that of Nd2Fe14B over the whole temperature region.

The novel quaternary compound Fe11–xCox TiCe (x = 0 to 3.25) of Mn12Th structure has been fabricated by arc melting. The analysis is focused on temperature dependent determination of intrinsic properties from 4 K to 750 K using domain pattern analysis and magnetometry. Above room temperature RT maximum values of anisotropy constant K1 and saturation polarization Js are observed for a Co content of 15 at% (x = 1.95) with K1 and Js of 2.15 MJ/m3 (1.22 MJ/m3) and 1.27 T (1.05 T) at RT (200 °C). At operating temperatures of 100 °C for this material magnetic properties (BH)max= 282 kJ/m3, µ0Hc = 0.94 T are expected. If a suitable microstructure could be processed, based on intrinsic properties of the phases the costs would be 35% per J/m3 of the costs of Dy-free Fe–Nd–B. (© 2014 WILEY-VCH Verlag GmbH &Co. KGaA, Weinheim)

Temperature-dependent ferroelectric dynamic hysteresis properties of modified Pb(Mg1/3Nb2/3)O3–Pb(Zr,Ti)O3 (PMN–PZT) ceramics have been investigated in a wide range from 298 to 433 K. Interestingly, it was found that back-switching polarization Pbc increased while the hysteresis area 〈A 〉, coercive field Ec, saturation polarization Ps, and remnant polarization Pr all decreased linearly with temperature below 398 K (close to the macro–micro domain transition temperature Tnr). A set of simple linear temperature scaling relations was established, which is different from the power-law scaling relations for soft and hard PZT ceramics. At further increased temperature, double-loop features appeared and the ferroelectric properties varied nonlinearly due to the reversible macro–micro domain transition in the T > Tnr region. (© 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

0.95 (Na0.5Bi0.5)TiO3–0.05 BaTiO3 + 2 wt% Bi2O3 (NBT–BT3) ceramic was used as a target and NBT–BT3 thin films were deposited at room temperature by changing the RF power from 75 W to 150 W. The thickness of the NBT–BT3 thin films increased from 203 to 478 nm as the RF power increased from 75 W to 150 W. At 75 W RF power, the deposited NBT–BT3 thin films displayed defective surfaces, whereas at RF power ≧ 100 W, the NBT–BT3 thin films displayed smooth surfaces. The grain sizes also increased with increasing RF power. In addition, the remanent polarization and saturation polarization increased with increasing RF power. The coercive field first increased, reached a maximum at 100 W, then decreased with increasing RF power.

In this study, SrBi4Ti4O15 (SBT) thin films were deposited onto the SiO2/p-Si(100) and Pt/Ti/SiO2/p-Si(100) substrates by using sol-gel method. After deposition, the SBT thin films were then heated by a rapid thermal annealing (RTA) process conducted in air for 1min at 600-800°C. The surface morphologies and the crystalline structures of the SBT thin films were investigated by using SEM and XRD patterns. The grain sizes increased and the pores decreased with rising RTA temperature. In addition, the coercive field decreased and the remanent polarization and saturation polarization increased with rising RTA temperature. The lnJ-E1/2 curves of the SBT thin films were also investigated to find the leakage current mechanisms correspond either to the Schottky emission or to the Poole-Frenkel emission.

Soft magnetic composites containing an organic binder and mixtures of two different soft magnetic particles – iron and nano-crystalline Fe73.5Si15.5B7Cu1Nb3 – in varying mixing ratios have been prepared at a total filler fraction x mag = 0.5 and examined regarding the magnetic properties. Results show that the coercivity is decreased by replacing the magnetically harder material with the magnetically softer material in the composite until a certain threshold value of the mixing ratio is reached. Above this threshold the coercivity stays nearly constant. Total losses P / f , saturation polarization J s and inner demagnetization factor N i follow a linear mixing rule. The composite’s permeability μ is a result of filler fraction, mixing ratio, coercivity, polarization and inner demagnetization factor and due to that complex dependence hardly predictable.

Effects of compressive stress on the ferroelectric properties of ceramics in PZT–PZN systems were investigated. (1 − x )Pb(Zr 1/2 Ti 1/2 )O 3 ( x Pb(Zn 1/3 Nb 2/3 )O 3 or (1 − x )PZT–( x )PZN ( x = 0.1–0.5) ceramics were prepared by a conventional mixed-oxide method. The ferroelectric properties under compressive stress of the PZT–PZN ceramics were observed at stress levels up to 170 MPa using a compressometer in conjunction with a modified Sawyer–Tower circuit. It was found that with increasing compressive stress the area of the ferroelectric hysteresis (P–E) loops, the saturation polarization ( P sat ), the remanent polarization ( P r ), and the coercive field ( E c ) decreased. These results were interpreted through the non-180° ferroelectric domain switching processes.

Effects of compressive stress on the ferroelectric properties of ceramics in PZT–PZN system were investigated. The ceramics with a formula (1− x )Pb(Zr 1/2 Ti 1/2 )O 3 – x Pb(Zn 1/3 Nb 2/3 )O 3 or (1− x )PZT–( x )PZN ( x = 0.1–0.5) were prepared by a conventional mixed-oxide method. The ferroelectric properties under the compressive stress of the PZT–PZN ceramics were observed at the stress levels up to 170 MPa using a compressometer in conjunction with a modified Sawyer–Tower circuit. It was found that with increasing compressive stress the area of the ferroelectric hysteresis ( P – E ) loops, the saturation polarization ( P sat ), the remnant polarization ( P r ), and the coercive field ( E c ) decreased. These results were interpreted through the non-180° ferroelastic domain switching processes.

In this work, effects of compressive stress on the ferroelectric properties of 0.7PMN–0.3PT ceramics were investigated. The ceramics with the formula (0.7)Pb(Mg1/3Nb2/3)O3-(0.3)PbTiO were prepared by a conventional mixed-oxide method. The ferroelectric properties under compressive stress were observed at stress up to 80 MPa using a compressometer in conjunction with a modified Sawyer-Tower circuit. The results showed that applied stress had a significant influence on the ferroelectric properties of 0.7PMN–0.3PT ceramics. Ferroelectric characteristics, i.e. the area of the ferroelectric hysteresis (P-E) loop, the saturation polarization (Psat), the remanent polarization (Pr) and loop squareness (Rsq), decreased with increasing compressive stress, while the coercive field (Ec) remained relatively constant. Stress-induced domain wall motion suppression and non-180oC ferroelectric domain switching processes are responsible for the changes observed.

Substituted M-type ferrite BaFe12−2x(Me1Me2)xO19, 0 ≤ x ≤ 0.6 was prepared by both mechanical alloying and precursor method, where Me1 = Co, Ni, Zn, Sn and Me2 =Ru, Ti, Zr, Sn. Magnetic phase purity, change of saturation polarization, Curie temperature, coercivity and magnetic susceptibility was studied as function of x. Attention was focused to results obtained for (NiRu)x, (ZnRu)x, and (SnRu)x mixtures with low doping ratio x.

PZT films with (1 0 0) and (1 1 0) orientation were prepared by spin coating using the chemical solution deposition (CSD) method on an SRO/Si or a Pt/Ti/SiO 2 /Si substrate. The remnant polarization and the saturation polarization of the PZT/SRO/Si film were 21 and 35 μC/cm 2 , and those of the PZT/Pt/Ti/SiO 2 /Si film were 20 and 31 μC/cm 2 . The remnant polarization of the PZT/SRO/Si film maintained more than 10 8 switching cycles, and the fatigue property was observed for the PZT film fabricated on the Pt/Ti/SiO 2 /Si electrode.

Acoustic emission (AE) has been studied during repeated polarization reversals (at 50 Hz) in hard PZT-8 ceramics. The AE and hysteresis loop were monitored at regular intervals of electric field (±20 kV cm−1 peak) application till 108 cycles. The sample did not fatigue and an increase in saturation polarization (Ps) was observed. AE was observed with zero threshold till 105 cycles when the field was increasing in both half cycles of the applied field. The initial increase in AE activity with increasing number of field cycles till 105 was explained on the basis of defect dipoles encouraging the 90° domain switches, i.e. domain depinning. The decrease in AE activity, an increase in threshold field for the observed AE and a further increase in Ps after 105 cycles were explained based on the changes in the orientation of defect dipoles with respect to Ps due to the applied field cycles. This was found to encourage the 180° domain switches but pin the 90° domains. An increase in AE at 108 cycles after applying a higher field of ±25 kV cm−1 was found to be mainly due to microcracking.

The measurements of a pyroelectric current generated by the TGS crystal previously exposed to the prolonged electric field E 3 parallel to the c-axis have been carried out. It has been found that the permanent transverse polarization P 3 ‖ c (i.e. perpendicular to the ferroelectric b-axis) appearing during the application of this field for the time interval Δ t can be expressed by the formula P 3 = P 3S [1-exp(-Δ t/τ)]. The saturation polarization level P 3S is at most only slightly dependent on the transverse field strength. On the other hand, the corresponding relaxation time τ markedly decreases as the field E 3 value is raised. A threshold transverse field of the order of 10 kV/m has been observed.

We propose a model of surface saturation polarization as the mechanism for the giant electrorheological (GER) effect, recently discovered in suspensions of coated nanoparticles dispersed in silicone oil. On the basis of this model, the distinguishing features of the GER fluid, such as the extremely high value of the static yield stress (exceeding the theoretical upper-bound) and its linear field-dependence, can be explained quantitatively. The current-field relation and the particle size-scaling effect are also addressed. The agreement between theory and experiments is excellent. We give a brief discussion on the role of electrowetting effect in the formation of surface aligned dipole layer(s).

A Green's function technique is used to investigate the properties of ferroelectric thin films in an external electric field. The thicker films reach the saturation polarization at much lower applied fields compared to the thinner films.

Piezoelectric applications such as ultrasonic motors, transformers and therapeutic ultrasonics demand high power generation with low losses, which is facilitated by “hard” ferroelectrics. Hardening of piezoelectric properties, characterized by high mechanical quality factor (Qm), is usually achieved by doping with lower valence elements, thereby tailoring the domain wall dynamics. In the present study, we demonstrate a hardening mechanism by developing composites of 0.94(Na1/2Bi1/2)TiO3-0.06BaTiO3 (NBT-6BT) with ZnO inclusions, as an alternative to chemical modifications. A decrease in the saturation polarization and total strain, higher internal bias fields, lower hysteretic losses and a two-fold increase in Qm are observed in comparison to NBT-6BT. The composite with 0.1 mole ratio of ZnO exhibits the highest Qm of 320 with d33 = 125 pC/N and Kp = 0.29. A one-to-one correspondence between the increase in Qm and the decrease in the domain wall mobility is established from the ac field dependence of permi...

This paper deals with the measurement of the magnetic properties of steel and other soft magnetic, electrical conductive, materials at high temperatures up to the Curie temperature and slightly above. At first the theory of measuring the magnetic properties at room temperature is described on the basis of the ring core method and the Epstein method, since aspects of both are used in the developed measurement setup for high temperatures. The heating of the ring-shaped steel sample is achieved by using it as the secondary, short-circuited winding of a transformer. The ring itself is thermally insulated and wound with two coils, which allow the determination of the magnetic properties. The measurements show that the saturation polarization is decreased a little bit up to 500 °C and then drops to zero at slightly above 700 °C. However the initial permeability is increased with temperature and the iron losses for low polarizations are decreased.

Dependence of the ferroelectric electron emission properties on the variables including the geometric ratio of the upper electrode diameter to the thickness of the ferroelectrics was investigated. Saturation polarization and dielectric constant increased with increasing the ferroelectric thickness and decreasing the upper electrode diameter. Electrons were emitted from the ferroelectric films above 2.0 μm with an emission charge comparable to that of the bulk ferroelectrics. As the ferroelectric thickness increased and the upper electrode diameter decreased, electrons were more easily emitted without breakdown. The effect of the ratio of the upper electrode diameter to the ferroelectric thickness on the emission properties was explained through the electric field simulation of the ferroelectric electron gun.

A new method for formation of large single grains as large as 40 μm in length of the sputter-deposited PZT(65/35) thin films has been developed in this research group. Crystallized PZT dots were used as a seed and the grains were laterally grown to form a square pattern on the Pt substrate. It turned out that the electrical characteristics of the single grained PZT thin films were much superior to those of the poly-grained PZT thin films. The leakage current was measured to be less than 8x10−8 A/cm2, the breakdown field more than 1,240 kV/cm, the value of saturation polarization and remanent polarization as high as 42 μC/cm2, 30 μC/cm2, respectively. No degradation of the polarization properties was observed even after the 2×1011 cycles at 1 MHz using a ± 10 V wave form in Pt/PZT/Pt structure. The accelerated retention test revealed that it takes more than 6×107 years for the remanent polarization to be reduced down to 80% of the original value.

A sol-gel technology to fabricate PZT thick film for cantilever beam was investigated. In this process, PZT nano-powder is dispersed into a PZT sol solution, which is identical with the powder in composition, and then the PZT suspension and clean PZT sol solution were deposited alternately on an Au/Cr/SiO2/Si substrate using spin-coating route. Above process was repeated in order to deposit the desired thickness. The results showed that the perovskite PZT thick film with thickness of about 4 μm was obtained after annealing at 650 °C for 2 h and it has the saturation polarization of 54 μC/cm2, the remnant polarization of 30 μC/cm2 and the coercive field of 50 kV/cm.

Melt-spun ribbon samples of various thicknesses up to 350 μ m and suction-cast 1 and 2 mm diameter rods of Fe 61 Co 10 + x Zr 5 W 4 - x B 20 ( x = 0 , 2 , 3 ) alloys, were produced. The results obtained for rods indicate relatively large saturation polarization J s , with high anisotropy field that lowers the permeability of the samples. X-ray diffractometry was applied to confirm the amorphous structure of the processed alloys.

The (0.90-x)Pb(In1/2Nb1/2)O3-xPbTiO 3-0.10PbZrO3 (PINTZ10) ceramics are prepared by solid state reaction and their structural, dielectric and piezoelectric properties near morphotrophic phase boundary (MPB) has been examined systematically. The structure undergoes a gradual change from rhombohedral to tetragonal when the PbTiO3 content (x) is increased. From the frequency and temperature dependent dielectric measurement it is found that the dielectric relaxation (?T) decreases with Ti4+ substitution. Even though the MPB of this ternary system is formed with lower PT content (0.62PIN-0.28PT-0.10PZ), the substitution of Zr4+ in the B site maintains the transition temperature (Tm) at 300 C resembling its binary, 0.67PIN-0.37PT. The higher saturation polarization obtained for x = 0.27 and the high piezoelectric co-efficient obtained for x = 0.29 substantiate the existence of MPB between these two compositions. � 2013 Springer Science+Business Media New York.

PZT thin film capacitors with the composition Pb(Zr0.53Ti0.47)O3 were deposited via metallo-organic decomposition (MOD) and rapid thermally processed (RTP) at a substrate temperature of 825°C. The photo-response of these capacitors was determined by measuring the change in saturation polarization and resistance as a function of incident photon energy prior to and after fatigue testing. We propose that photo-generated free carriers can screen and/or recombine with trapped charge which restores local charge equilibrium within the PZT capacitor and hence, temporarily restores polarization.

NdFeB films are prepared by dc sputtering. The dependence of the film properties on sputtering parameters is investigated by analysing the surface morphology, crystalline structure, and magnetic properties for different preparation conditions. c-textured films are prepared with a coercivity of up to 0.2 T, a saturation polarization of 1.6 T, and a remanent polarization of 0.4 T. Special emphasis is given to the preparation conditions such that the surface roughness of films with sufficient magnetic performance is well below 100 nm, making these films suitable for micropatterning. NdFeB-Schichten werden mittels dc-Kathodenzerstaubung prapariert. Fur unterschiedliche Praparationsbedingungen beim Sputterprozes werden die Schichteigenschaften hinsichtlich Oberflachenmorphologie, Kristallstruktur und magnetischem Verhalten untersucht. Es konnen Filme mit c-Achsen-Textur hergestellt werden, welche eine Koerzitivkraft von 0,2 T, eine Sattigungsmagnetisierung von 1,6 T und eine Remanenz von 0,4 T aufweisen. Die Praparationsbedingungen werden insbesondere daraufhin variiert, das eine Oberflachenrauhigkeit der Filme bei Wahrung ausreichender magnetischer Eigenschaften von unter 100 nm erreicht wird. Hierdurch werden diese Filme fur Zwecke der Mikrostrukturierung geeignet.

A family of rapidly quenched alloys based on pig iron (PI) having 6–10 at% additions (B, Ge, Ga,Al) has been found. In spite of small crystalline fraction, the best sample has the interesting values of resistivity, saturation polarization and magnetostriction of 129 μΩ cm , 1.59 T and 1.3 ppm , respectively. The AC power losses of these alloys were found comparable with those of the commercial glassy alloys.

For the present study, La substituted PZT ceramics having compositional formula Pb1−3x/2LaxZr0.65Ti0.35O3 were prepared by conventional solid state method. La content was varied from x = 0 to 0.03 in the steps of 0.01. XRD analyses of all the samples were done and were found to have single phase with rhombohedral structure. In this paper, we are reporting the variation in ferroelectric properties of Pb1−3x/2LaxZr0.65Ti0.35O3 by varying La content. P‐E hysteresis loops were recorded using P‐E loop tracer based on Sawyer‐ Tower circuit for all the samples at 20 Hz. Increase in coercive field (Ec), remanant polarization (Pr), saturation polarization (Ps) and squareness ratio (Pr/Ps) was observed with increase in x.

Pyrochlore free lead indium niobate ceramics are successfully prepared using wolframite precursor by conventional solid state reaction method in air atmosphere, by adding an excess amount of MgO in PbO-InNbO4 mixture. The dielectric properties of lead indium niobate ceramic studied as a function of both temperature and frequency indicate relaxor ferroelectric behavior with maximum dielectric constant of 4310 at 40 C for 1 kHz. Lowering of transition temperature and enhancement of dielectric constant at room temperature, compared to earlier reports, may be due to the diffusion of magnesium ion into the lead indium niobate. The saturation polarization Ps, measured at room temperature, is found to be 22.5 ?C/cm2 for 40 kV/cm. � 2010 Elsevier Ltd. All rights reserved.

The existence of interstitial Sm2Fe17Nx with intermediate nitrogen contents (0 ≤ x ≤ 2.94) is revealed by a continuous increase of the unit cell volume, the Curie temperature, the saturation polarization and the anisotropy field with increasing N concentration. The thermal stability of Sm2Fe17Nx increases also with increasing x. The anisotropy constants K1 and K2 at room temperature were deduced by fitting magnetization curves of oriented powders. The easy magnetization direction changes from the basal plane (x = 0) via an easy cone (δ = 24 ° forx = 0.4) to the c-axis (x ≥ 0.55). The intrinsic magnetic properties of Sm2Fe17N2.94 were found to be Tc = 473 ° C, Js = 1.51 T and HA = 21.0 T where K1 = 8.4 and K2 = 2.1 MJ/m3.

A quantitative fatigue model is proposed for ferroelectric thin films on the basis of effective one-directional movement of defects due to asymmetric polarization under alternating pulses, defect entrapment at electrode-ferroelectric interface (and/or at grain and domain boundaries), and the resultant polarization loss at these surfaces due to structural damage. A fatigue equation is derived in accordance with this model and three fatigue parameters such as initial saturation polarization, piling constant, and decay constant are defined. The predicted values from the model show very good agreement with experimental data. Temperature and voltage dependence of fatigue parameters are studied on the basis of the fatigue model. The jump distance of defects is calculated from the voltage dependence of the decay constant which turns out essentially to be the same as the lattice parameter. Based on the fatigue model, an improved method to overcome fatigue property is also presented. Un modele quantitatif de tenue en fatigue de films ferroelectriques minces est propose sur la base de mouvements effectifs unidirectionnels des defauts cause par polarization asymetrique sous impulsions alternatives, capture des defauts a l'interface electrode-ferroelectrique (et/ou celle des frontieres de grains at de domaines), et la perte de polarisation resultante dans des surfaces a ete obtenue en accord avec ce modele et trois parametres de fatigue tel que la polarisation de saturation initiale, la constante d'empilement et la constante de deterioration ont ete definis. Les valeurs predites par le model montrent un tres bon accord avec les resultats experimentaux. La dependance des parametres de fatigue en fonction de la temperature et du voltage ont ete etudies sur la base du modele de fatigue. La distance de saut (qui apparait en fait ětre pratiquement egale au parametre de lattice) des defauts a ete calcule a partir de la dependance de la constante de deterioration en fonction du voltage. Sur la base de ce modele de fatigue, une methode pour ameliorer les proprietes de tenue en fatigue est presentee.

Formation and magnetic properties of the interstitial Th2Zn17-type nitrides were investigated over the whole concentration range for Sm2(Fe1−xCox)17. The decomposition temperature, Td, and the nitrogenation kinetics decrease with increasing Co content x. The substitution of Co for Fe, for x < 0.2, leads to an overall improvement of the intrinsic magnetic properties of Sm2Fe17Ny. The Curie temperature, the room temperature saturation polarization and the anisotropy field show a maximum in dependence on composition for x = 0.5 (TC = 901 K), x = 0.15 (Js = 1.55 T) and x = 0.3 (HA = 25.0 T), respectively. For Sm2Co17, nitrogenation considerably decreases the Curie temperature and the saturation polarization whereas the anisotropy field is almost doubled. For x = 0.2 the compound has excellent intrinsic magnetic properties for hard magnetic applications: TC = 842 K, Js = 1.55 T and HA = 23.7 T at room temperature.