Increasing Sm Content Research Articles

Spin reorientation, spin switching, and magnetic compensation in Er1−xSmxFeO3 single crystals

We investigated spin reorientation, magnetic compensation and spin switching transitions in a series of high-quality single crystals of Er1−xSmxFeO3 (x = 0, 0.2, 0.4, 0.6, 0.8) prepared using the optical floating zone method. Structural and other preliminary characterizations confirmed the quality and phase purity of the crystals. Rietveld refinement of powder XRD data indicates that lattice parameters a and c increase linearly with increasing Sm concentration, whereas b remained constant. Field-cooled cooling (FCC) measurements revealed a temperature-induced spin reorientation transition (SRT) from Γ4 (Gx, Ay, Fz) to Γ2 (Fx, Cy, Gz) for all the samples. SRT temperature increased with Sm concentration and spread widely above and below room temperature. Moreover, magnetic compensation is common to all the compositions but decreases as Sm doping increases. We also observe type-I spin switching in samples with x = 0, 0.2, and 0.4 at an applied field of 60 Oe under FCC protocol, with a reduction in spin switching temperature as Sm content increased. For Sm-rich samples (x = 0.6, 0.8), spin switching was absent at 60 Oe.

Probing of structural, electrical, and dielectric properties of samarium doped composite of barium titanate (Ba0.5Sm0.5TiO3) and cobalt ferrite (Co0.5Sm0.5Fe2O4)

Multiferroic composites exhibit remarkable magnetoelectric (ME) characteristics, offering diverse applications. The study investigated samarium (Sm) doped composites, specifically (1 − x)Ba0.5Sm0.5TiO3–xCo0.5Sm0.5Fe2O4 (x = 0.0,0.02,0.04,0.06), formed by combining Sm doped BaTiO3 and CoFe2O4 using the solid-state reaction method. X-ray diffraction analysis revealed a tetragonal structure in Ba0.5Sm0.5TiO3 (SmBT) and a cubic spinel secondary phase in Co0.5Sm0.5Fe2O4 (SmCF), suggesting uniform distribution of grains. The optical bandgap in SmBT and the composite showed a slight decrease (from 3.14 eV to 3.01 eV) with increasing Sm concentration, as observed in optical studies. The dielectric measurements showed that the dielectric constant of SmBT was higher (ϵ′ = 526.3) between 80 Hz and 8 MHz, while the composites had a lower dielectric constant (ϵ′ = 438.4) at lower frequencies and the real part of dielectric was fitted by Havriliak–Negami (H–N) model shows that the dielectric curves exhibit a characteristic dispersion pattern known as the cole–cole mode (grains) also confirmed by cole–cole plot. The response exhibited linearity, adhering to the universal dielectric response model. Ferroelectric behaviour in the underlying material confirms SmBT non-centrosymmetric character and the storage efficiency (η) of all composites surpassed 90%, reaching a peak of 94.8% with a ferrite content of 0.02. The versatility of the Sm-doped composites offers opportunities for diverse applications in fields such as electronics, telecommunications, and biomedical devices. Notably, these materials can be utilized in Memory Devices, Actuators, and other relevant applications.

Structural heterogeneity induced enhancement of physical properties in Sm‐modified K0.5Na0.5NbO3

AbstractDoping of suitable metal ions in ferroelectric oxides modifies the physical properties and can induce additional functionalities. Here, we present a detailed study on the effects of Sm concentration on the structural, dielectric, ferroelectric, and piezoelectric properties of ((K0.5Na0.5)1−3xSmx)NbO3 (KNSN) (0.00 ≤ x ≤ 0.02) ceramics. X‐ray diffraction and Raman spectroscopic analysis indicate that KNSN ceramics exhibit the single‐phase orthorhombic (Amm2) structure for x = 0.00 and the coexistence of orthorhombic and tetragonal (Amm2 + P4mm) structure for the composition range 0.005 ≤ x ≤ 0.02. The tetragonal phase fraction increases with an increase in Sm concentration. We observed dielectric relaxation behavior in KNSN at orthorhombic to tetragonal (TO–T) phase transition temperature, and its origin can be attributed to the structural heterogeneity at the inter‐ferroelectric phase boundary. Increasing Sm concentration leads to the broadening of the ferroelectric phase transition peaks. Further, the structural heterogeneity of the ceramics was seen from the slope of the dielectric constant versus log frequency and central peak behavior of Raman spectra at room temperature (RT). The study reveals that x = 0.005 shows maximum dielectric constant (Ɛr = 583), remanent polarization (2Pr = 57.02 μC/cm2), and piezoelectric coefficient (d33 = 94 pC/N) at RT and is associated with increased local structural heterogeneity due to Sm doping.

The impact of Sm substitution on structural and optical properties of LaFeO3: their application as a photocatalyst for the degradation of methylene blue under visible light irradiation

The objective of the present study is to enhance the photocatalytic activity of LaFeO3 by inserting Sm ions on the La site for the degradation of methylene blue. We employed citric sol–gel techniques to produce ultrafine powders of the La1-xSmxFeO3 (0.0 ≤ x ≤ 0.5) nanoperovskite samples. All samples confirmed the presence of a pure Pbnm orthorhombic phase structure. The decrease of lattice constants, crystallite sizes and cell volumes, and increase in microstrains suggest a deformation of the structure due to the addition of Sm ion on the La site of the La1-xSmxFeO3. The images of HR-TEM and FE-SEM for all samples revealed a homogeneous distribution of almost spherical nanoparticles, with decreasing average particle sizes ranging from 49.95 ± 3.12 to 34.28 ± 4.38 nm, as Sm ratios increases from 0.0 to 0.5%. The spectra of FTIR confirmed the formation of a Lax-1SmxFeO3 perovskite phase by the appearance of lower frequency bands Fe–O-Fe and La-O-La at ∼ 400 cm−1 and a higher absorption band Fe -O and La -O at ∼ 564 cm−1. The Raman spectra were employed to investigate the formation of phonon modes of La1-xSmxFeO3. Diffused reflectance spectroscopy (DRS) demonstrated the decrease of energy gap (Eg) values from 2.38 to 1.86 eV and the increase in Sm content from 0.0 to 0.5%. Since these Eg values fall within the visible light region, the photocatalytic activity of La1-xSmxFeO3 samples demonstrated a gradual increase in the degradation ratio of MB from 31.7 to 73.2% with increasing Sm content from 0.0 to 0.5%, respectively, under visible light illumination.

Understanding of structural evolution, dielectric performance, and photoluminescence behavior of Sm-modified Na0.5Bi0.5TiO3

We present the crystal structures, dielectric and optical performance of Samarium doped NBT ceramic, (Bi(1−x)Smx)0.5Na0.5TiO3for x = 0.0, 0.01, 0.02, 0.03, 0.04, 0.05 fabricated by a solid-state reaction method. The Rietveld refinement outcomes of XRD data show that all the samples have rhombohedral crystal structures with the R3c space group. The variation of unit cell volume with composition displays an anomaly at x = 0.03. The Raman modes centered at 258 cm−1 and 535 cm−1 become broader with trivial smearing towards higher wavelength through a rise in Sm percentage. The temperature corresponding to maximum permittivity attains maximum value at x = 0.03. We found that dielectric loss decreases with increasing Sm content. The diffusing nature of the phase transition is enhanced with the rise in dopant concentration of Sm. The bandgap energy obtained from the reflectance data of UV–visible spectroscopy increases x = 0.03 and afterward simultaneously diminishes with Sm concentration. The photoluminescence study was carried out using the excitation spectra and emission spectra. The most intense emission has been observed at x = 0.03. Besides, a feeble green emission peak at 564 nm and two burly red emission peaks at 600 nm and 646 nm correspond to the 4G5/2→6H5/2 transition, and 4G5/2→6H7/2 and 4G5/2→6H9/2 transitions respectively. We expect that the incorporation of Sm in the NBT system will be a suitable method to highlight the multifunctional characteristics of the material for potential applications in devices having manifold functions incorporated with electrical and luminescence properties.

Dielectric, ferroelectric, and piezoelectric properties of rare earth Sm-doped 0.94 Bi0.5Na0.5TiO3-0.06 BaTiO3 lead-free ceramics

Bi0.47-xSmxNa0.47Ba0.06TiO3 (BNT-6BT-xSm) ferroelectric ceramics with different doping contents of samarium (Sm) were prepared by solid-state reaction method. All ceramics lie in the coexistence region of the rhombohedral perovskite phase (R3c) and tetragonal perovskite phase (P4bm). When the Sm content increases, the grain growth is limited, and the average grain size is reduced from 1.69 µm (at the composition of x = 0.005) to 0.86 µm (at the composition of x = 0.05). When Sm is introduced into Bi0.5Na0.5TiO3-BaTiO3 binary system, the composition-induced local structure transition occurs, namely the transition from order to disorder. And after the introduction of Sm3+ ions, the depolarization temperature (Td) increases considerably. With the increase of the Sm content, the remnant polarization (Pr) decreases from 52 μC/cm2 to 8 μC/cm2, and the coercive field (Ec) gradually decreases from 37 kV/cm to 14 kV/cm, respectively. Under an electric field of 80 kV/cm, the maximum electric field-induced strain and corresponding normalized strain (d33*) reached 0.35% and 318 pm/V (at the composition of x = 0.03), respectively. The maximum piezoelectric coefficient (d33) is 158 pC/N (at the composition of x = 0.015), resulting from the structure transition between ferroelectric phase and anti-ferroelectric phase. Therefore, BNT-6BT-0.03Sm lead-free ferroelectric ceramic is a promising candidate of lead-based ferroelectric ceramics for piezoelectric actuators.

Pure and Sm doped CeO2 Nanoparticles: An insight into the Room Temperature Ferromagnetism and Photocatalytic Dye Degradation

AbstractCeO2 nanoparticles (7–28 nm) and Sm‐doped (5, 10, 15, and 20 %) CeO2 nanoparticles are synthesized using a simple chemical precipitation technique. The defects are studied using Raman spectroscopy, and the presence of defects as oxygen vacancies is verified using the longitudinal optical mode. The optical band gap is determined using UV‐Vis spectroscopy. The reduction in the optical band gap with increasing particle size might be related to quantum confinement, which causes localized states to form due to oxygen vacancies when Ce4+ is reduced to Ce3+. An increase in band gap is observed with increasing Sm concentration, and the optical band gap is smaller than pure CeO2. The electronic structure is investigated using the X‐ray photoelectron spectroscopy (XPS) method, which studied the contributions of each ionic state, namely Ce3+ and Ce4+. Room temperature ferromagnetism (RTFM) is observed for doped as well as undoped samples. The saturation magnetization for 28 nm pure CeO2 NPs is obtained as Ms=5.6*10−4 emu/g, whereas for Sm‐doped samples, we found an increased value of 3.5*10−2 emu/g. The samples are scrutinized for UV‐irradiated photocatalytic dye degradation. The origin of RTFM behaviour and efficient photocatalytic activity are from oxygen vacancies at the lattice sites.

Comparison of the Multiferroic Properties of Ion‐Doped Hexagonal LuFeO3 and LaFeO3

Using a microscopic model, the magnetic and electric properties of pure and ion‐doped (on the Lu or Fe sites) hexagonal LuFeO3 (LuFO) are studied and compared with the properties of ion‐doped LaFeO3 (LaFO). The magnetization increases by Sr and Sc doping which is caused by the strain and the changes of the exchange interaction constants at the doped states. It is observed that by Sm doping of LuFO the polarization decreases, whereas by Sm doping of LaFO, the polarization increases with increasing Sm concentration. By Ir or Co ion doping on the Fe site, the magnetization and the phonon energy increase whereas the bandgap energy decreases. By doping on the Fe sites with the same ion, for example, Sc, there are no differences between LuFO and LaFO. A good agreement with the experimental data is observed. The doping effects can be used for different applications.

Probing structural, optical and magnetic properties of Sm-doped ZnO nanomaterials via experimental and DFT approach: Enhanced photocatalytic degradation and antibacterial performance

We prepared the pristine and Sm3+-doped ZnO nanostructures using an eco-friendly ball milling technique and investigated the physical properties of nanostructures by experimental methods and density functional theory approach. The reduction in crystallite size and increment in structural defects was witnessed due to Sm-doping. Decrease in band gap (from 3.27 to 3.02 eV) and enhancement of magnetic properties were observed with the increase in dopant concentration. The photocatalytic degradation potential of the samples towards the pollutants methylene blue (dye) and ciprofloxacin (antibiotic) improved with Sm3+ doping. The best performance was witnessed for the sample doped with 4 mol% of Sm2O3, which degraded the 93% and 95% of methylene blue (50 ppm) and ciprofloxacin (25 ppm) in 150 min and 210 min, respectively. Antibacterial activity towards the Escherichia coli and Staphylococcus aureus bacteria was also enhanced with the increase of Sm-content. Thus, Sm-doped ZnO nanostructures show good potential for photocatalytic and antibacterial applications.

Structural, magnetic and magnetocaloric properties of Laves phase (Gd,Sm)Co[formula omitted] compound

In the present work, the structural, magnetic, and magnetocaloric properties of the intermetallic Gd1−xSmxCo2 (x=0.5,0.6 and 0.7) compounds have been systematically studied. Samples were prepared by arc melting under high pure argon and homogenized at 800 K to minimize the impurity phases. X-ray diffraction (XRD) coupled with Rietveld analysis has shown that all samples crystallize in the cubic MgCu2-type structure (Space group Fd-3 m). Refinement results show that the unit cell parameter increases with increasing Sm content. The magnetic measurement reveals that the Sm content reduces the Curie temperature TC from 404 (for x=0) to 263 K (for x=0.7). The magnetic entropy change of the samples as function of temperature and applied magnetic field were calculated from the isothermal magnetization curves using Maxwell relation. The relative cooling power RCP and the temperature-averaged entropy change (TEC) have been reported. Furthermore, the magnetocaloric behavior is studied using the scaling laws and the phenomenological universal curve.

Dielectric relaxation and charge carrier mechanism in doped Ce1-xSmxO2-δ (0 ≤ x ≤ 0.3) nanoceramics: An investigation with dielectric spectroscopy

We present herein the structural, dielectric, and ionic conduction properties of a series of doped Ce1-xSmxO2-δ (0 ≤ x ≤ 0.3) nanocrystalline ceramics. X-ray photoelectron spectroscopy studies have indicated a non-stoichiometry induced mixed Ce4+ and Ce3+ charge state, with the content of Ce3+ ions decreasing with increasing Sm concentration. Analysis of impedance data has suggested that both grains and grain boundaries contribute to the overall conductivity, but grain boundaries make the dominant contribution. Further, we have observed an enhancement in conductivity, which can be attributed to reduced grain size and increased interfaces in these nanostructured materials that lead to faster ionic diffusion across the boundaries. While our results suggest that dopant vacancy related high frequency relaxation is active in all the materials, for the sample with x = 0.2 we have found two Debye-type dipoles in the relaxation process, with an additional low frequency dipole relaxation due to long-range migration of free oxygen vacancies. This migration is responsible for high conductivity in Ce0.8Sm0.2O2-δ, making the compound an ideal candidate for applications.

Effect of Sm3+ doped Ni-Cd Nano ferrite synthesis and structural characterization by citrate-gel auto combustion method

Ferrite nano particles of basic composition Ni Cd Smx Fe2-xO4(0.0 ≤ x ≤ 0.05, X=0.01) where synthesized by citrate-gel auto combustion method have investigated. X-ray diffraction profile indicates that the samples are in single phase structure for the sample without Sm content. For the samples with Sm ions, some diffraction peaks appeared which belongs to the orthorhombic phase structure further, the XRD have been used calculated the lattice parameter, density and grain size. The particle size of the starting powder composition varied from 30 nm to 45 nm. The values of lattice parameter (a) decreased and X-ray density (dx) increased with the increase of Sm content. Morphology of the prepared samples by citrate-gel method was studied using scanning electron microscope (SEM). The elemental analysis of all the Ni-Cd-Sm ferrite samples with different compositions was analyzed by Energy Dispersive Spectrometer (EDS). The observed results can be explained on the basis of composition and crystal size.

Increased intrinsic anomalous Hall effect from rare earth content in amorphous SmxCo1−x films

The low temperature anomalous Hall effect in amorphous sputtered SmxCo1−x films is investigated. The microstructure and amorphous nature of the films were characterized by local area diffraction through transmission electron microscopy. The Sm/Co ratio was changed to elucidate the origin of the anomalous Hall effect, which is a proxy for spin polarized transport. The anomalous Hall effect obeys a scaling relation that points to an intrinsic Berry-curvature based mechanism, consistent with recent reports on other amorphous magnetic materials. The anomalous Hall angle increases with increasing Sm content and reaches large values of ∼1%. This observation is related to recent measurements of the local structure in amorphous Sm–Co alloys and suggests that rare earth elements can be utilized to improve electrical control over spin polarization in amorphous magnetic films.

Achieving ultra-short discharge time and high energy density in lead-based antiferroelectric ceramics by A-site substitution

Antiferroelectric (AFE) ceramic capacitors are promising candidates for energy storage applications in advanced pulsed power capacitors (APPCs) due to the high-power density. Nevertheless, the incompatibility between discharge time and energy storage density limits their practical application in APPCs. Herein, we present ultra-short discharge time and high energy density performances of (Pb1-1.5xSmx)(Zr0.6Sn0.4)O3 AFE ceramics by A-site Sm modification strategy. Ultrafast discharge rate (t0.9) of ∼ 57.1 ns and high recoverable energy density of ∼ 11.2 J/cm3 (energy efficiency of 85.1%) at 400 kV/cm are achieved simultaneously in (Pb0.94Sm0.04)(Zr0.6Sn0.4)O3 ceramic. The t0.9 of AFE ceramics directly related to phase-switching fields, which is confirmed by variable electric field test. Sm modification is contribution to enhancing the interaction among the ions by reduction of tolerance factor, and strengthening phase-switching fields, leading to improving the stability of AFE state, which is confirmed by XRD, Raman, SEM, XPS profiles and P-E curves. As a result, the t0.9 is decreased from 87.2 to 51.1 ns, corresponding to large discharge energy density (∼9.7 J/cm3) owing to high breakdown strength by refining average grain sizes with increasing Sm content. Meanwhile, this ceramic has good fatigue resistance in terms of frequency and temperature. These results would provide a reliable strategy for the design and application of APPCs.

Enhancement of magnetic properties and microstructural changes in TbCu7-type Sm-Fe-Co-Nb-B melt-spun ribbons

The effects of annealing conditions on magnetic properties, phase, and microstructural changes in Sm-Fe-Co-Nb-B melt-spun ribbons were investigated, and the dependence of magnetic properties on Sm and B composition was also investigated. SmxFe80.9−(x+y)Co16.4Nb2.7By amorphous ribbons were prepared by melt-spinning and then annealing. After annealing at 625 °C, the Sm6.2Fe66.4Co16.4Nb2.7B8.3 ribbons exhibited crystallization of hard-magnetic TbCu7-type phase, and the coercivity increased as the annealing time was increased to 9 h. The grain size of the TbCu7-type phase as estimated from transmission electron microscopy (TEM) images was 20–50 nm for ribbons annealed for 9 h. Three-dimensional atom probe (3DAP) analysis revealed that Nb and B became enriched at grain boundaries and tended to condense at the grain boundaries with increasing annealing time. Non-magnetic Nb and B enrichment at the grain boundaries in fine TbCu7-type grains thus promotes magnetic decoupling between TbCu7-type phases and suppresses domain wall propagation, resulting in high coercivity. Composition dependence on magnetic properties was investigated. Optimum annealing time tended to increase with increasing Sm content. The Sm6.7Fe65.9Co16.4Nb2.7B8.3 ribbons exhibited a maximum coercivity of 695 kA⋅m−1 by annealing at 625 °C for 21 h and subsequent slow cooling at a cooling rate of 4 °C⋅h−1. As B content decreased, coercivity decreased and remanence increased. The Sm6.2Fe68.7Co16.4Nb2.7B6.0 ribbons exhibited a high σr of 100 A⋅m2⋅kg−1 and moderate HcJ of 540 kA⋅m−1 after optimal annealing. An isotropic bonded magnet was fabricated from this ribbon. The bonded magnet exhibited high magnetic properties of Br = 0.82 T, HcJ = 538 kA⋅m−1, and (BH)max = 98 kJ⋅m−3, and small temperature coefficients of α(Br) = −0.06%⋅°C−1 and β(HcJ) = −0.27%⋅°C−1.

Interconnected effects of Sm-doping on grain structure and transport properties of the textured Bi2-xSmxTe2.7Se0.3 compounds

Textured Bi2-xSmxTe2.7Se0.3 compounds with x ​= ​0; 0.005; 0.01; 0.02; 0.05; 0.1; 0.2 and 0.3 were prepared by using solvothermal synthesis and spark plasma sintering of starting powders. Sm-doping results in several interconnected effects. First of them is reducing in size of particles in starting powders with increasing x. This effect is attributed to increasing in ionic bonding fraction in polar covalent Bi(Sm)-Te bonds, which occurs at increasing Sm content due to difference in electronegativity of Bi and Sm. With increasing x, grain size in bulk samples is also reducing, which is governed by relevant changing in the size of particles. This effect also results in enhancing in texturing degree in samples at gradual increasing x. Finally, grain size effects on the specific electrical resistivity and the thermal conductivity are observed in bulk samples with different grain size. With increasing the grain size, the resistivity increases, whereas the total thermal conductivity decreases. These features are due to electron scattering by grain boundaries.

Improved dielectric and piezoelectric properties of Sm-doped Pb(Mg1/3Nb2/3)O3–Pb(Zn1/3Nb2/3)-PbTiO3 ternary ferroelectric ceramics

Sm-doped Pb(Mg1/3Nb2/3)-PbTiO3 (PMN-PT) binary ferroelectric ceramics has received extensive attention due to the excellent dielectric and piezoelectric properties. However, its Curie temperature (Tc) is greatly reduced by Sm doping and Tc is only 89 °C at the optimum piezoelectric coefficient. In this work, Sm-doped Pb(Mg1/3Nb2/3)O3–Pb(Zn1/3Nb2/3)-PbTiO3 (Sm: PMN-PZN-PT) ternary ferroelectric ceramics near MPB were successfully manufactured and the crystal structure, microstructure and electric properties were investigated with respect to Sm doping content. A high piezoelectric coefficient of 870 pC/N and a high Tc of 146 °C were achieved simultaneously in PMN-PZN-PT ternary ceramics with 1% Sm doping content. In addition, the room temperature dielectric constant was greatly improved by Sm doping and the Pr, Ps and Ec values gradually decrease with the increase of Sm content. These results indicate that Sm-doped PMN-PZN-PT ceramics may be an attractive material for high performance piezoelectric device applications.

Microstructures and High-Temperature Properties of Sm-Modified Mg-4Al-4RE Alloy

The effect of Sm on the microstructure and tensile properties of Mg-4Al-4 (La, Ce) alloy was studied. The Mg-4Al-4 (La, Ce) alloy was mainly composed of α-Mg and Al11(La, Ce)3. With the addition of Sm, a new phase of Al2(La, Ce, Sm) was revealed in the alloy. The results showed that at room temperature (RT), after Sm addition, the ultimate tensile stress and the elongation decreased, while the yield stress increased slightly; the elongation increased with the Sm addition and the yield stress was basically the same, but the ultimate tensile stress decreased at an elevated temperature of 150 °C. The change in the mechanical properties of the alloy was mainly related to the change in microstructure and phase. With the increase in Sm content, the volume fraction of Al2(La, Ce, Sm) phase increased and the Al11(La, Ce)3 eutectic volume fraction decreased significantly, which led to a change in the mechanical properties of the alloy. The 1 wt.%Sm-addition alloy exhibited greater elongation than the Sm-free alloys.

Microstructure and texture evolution with Sm addition in extruded Mg–Gd–Sm–Zr alloy

We prepared as-extruded Mg-10Gd-xSm (x = 1, 3, 5)-0.5Zr alloys by indirect extrusion, and the microstructure, texture and mechanical properties of as-extruded Mg-10Gd-xSm-0.5Zr alloys were investigated. The results indicate that the microstructure, texture and strength of as-extruded Mg-10Gd-xSm-0.5Zr alloys take a great variation with Sm addition. Dynamic recrystallized grain size is decreased with increasing Sm content, and the average grain size rapidly reduced to 1.4 μm in as-extruded Mg-10Gd-5Sm-0.5Zr alloys due to abundant Mg5(Gd, Sm) and Mg41(Gd, Sm)5 precipitates and their pinning effect on grain boundaries. With an increasing Sm content, the texture has a significant variation. The fiber texture with 〈10-10〉 axis of Mg matrix parallel to extrusion direction (ED) in as-extruded Mg-10Gd-1Sm-0.5Zr alloy transformed into an abnormal texture with 〈0001〉 axis of Mg matrix parallel to ED in as-extruded Mg-10Gd-3Sm-0.5Zr alloy. The tensile yield strength and Brinell hardness gradually increase with Sm addition due to soild solution strengthening, refined grain boundaries strength and numerous precipitates strengthening. However, the as-extruded Mg-10Gd-5Sm-0.5Zr alloy exhibits the poor ductility due to stress concentration caused by abundant precipitates.

Improved piezoelectric properties of Pb(Mg1/3Nb2/3)O3-PbTiO3 textured ferroelectric ceramics via Sm-doping method

Sm-doped Pb(Mg1/3Nb2/3)O3-PbTiO3 (Sm: PMN-PT) textured ceramics were fabricated by Template Grain Growth (TGG) using plate-like<001>oriented BaTiO3 (BT) as templates. The effects of PT and Sm contents on the crystal structure, microstructure, and piezoelectric, dielectric and ferroelectric properties of Sm: PMN-PT textured ceramics were investigated in details. Sm-doping was found to effectively improve the piezoelectric and dielectric properties of PMN-PT textured ceramics. For 1.9 mol% Sm: PMN-29PT textured ceramics with the Lotgering factor of 0.90, the piezoelectric coefficient d33 can reach up to 1040 pC/N. The relaxation behavior for Sm: PMN-29PT textured ceramics progressively increase with increasing Sm content. The room temperature dielectric constants of Sm: PMN-29PT textured ceramics continuously increase with increasing Sm contents and are not sensitive to increasing PT contents, while the temperature of the maximum dielectric constant continuously decreases with increasing Sm contents and increases with increasing PT contents. The saturation polarization and remnant polarization of Sm: PMN-29PT textured ceramics gradually decrease with increasing Sm content while the coercive field is not enlarged. This novel Sm: PMN-PT textured ceramics will further provide a new promising application prospect for ultrasonics, actuators, and transducers.