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Energy demands are increasing daily, driven by the growth of developing countries and their populations. Supercapacitors have been employed extensively in the field of energy in recent years due to their high energy density, rapid charge-discharge rates, and long-lasting structures. In this study, the electrochemical properties of CeO 2 varying with different types of additives were investigated. Four different compounds were synthesized using Ba, Er, and Tb. Syntheses were carried out with the sol-gel method, and X-ray diffraction and Raman spectra were used in crystal structure analysis. It was determined that the crystal lattice was cubic and it possessed Ce-O vibration bands and oxygen vacancy structures. Morphological features were determined by field-emission scanning electron microscope and Brunauer–Emmett–Teller analysis. Cyclic voltammetry measurements were performed for electrochemical properties. According to all results, the highest capacitance was calculated as 1752 F g−1 for the Ba-Er-doped ternary CeO 2 compound. • In this study, we report the electrochemical properties of CeO 2 varying with different types of additives were investigated. Four different compounds were synthesized using Ba, Er, and Tb. • The prepared CeO 2 -based materials were characterized with X-ray diffraction (XRD), field-emission scanning electron microscope (FE-SEM), Brunauer–Emmett–Teller (BET). • Co-doping the CeO 2 with both Ba and Er was found to enhance the effective charge transport. • Metal-doped CeO 2 exhibits enhanced specific capacitance and may be efficient when used in conjunction with carbon-based materials. [ABSTRACT FROM AUTHOR]

Cu-12.5Ni-5Sn-xY alloy with different rare earth Y contents was prepared by spark plasma sintering (SPS). The samples underwent aging at approximately 400°C for 4 hours in an energy-saving box furnace. The effect of trace Y addition on the microstructure and corrosion behavior of aging treated Cu-12.5Ni-5Sn-xY alloy were investigated by electrochemical test, and the corrosion mechanism of the alloy was discussed. The results indicated that the addition of rare earth Y improved the uniformity of microstructure and grain size of the alloy, and improved the corrosion resistance of the alloy. When the Y content changed between 0 wt% and 1.0 wt%, the corrosion resistance of the Cu-12.5Ni-5Sn-xY alloy gradually improved. The Cu-12.5Ni-5Sn-1.0Y alloy had a lower self-corrosion current density (1.490×10−5A/cm2) and a lower corrosion rate (0.178 mm/a). Compared to the Cu-12.5Ni-5Sn alloy without Y addition, the maximum corrosion depth was reduced by about 44.6 % and the corrosion resistance was improved. Rare earth Y promoted the uniform distribution of Ni elements, inhibited the conversion of Cu 2 O to Cu 2 (OH) 3 Cl, enhanced the layer density and stability. The internal corrosion layer mainly consisted of NiO, the intermediate layer mainly consisted of SnO, and the surface layer mainly comprised of CuO, Cu 2 O, and Cu 2 (OH) 3 Cl. Additionally, Y 2 O 3 formed on the alloy's surface, effectively prevented corrosive ion attack and enhanced the corrosion resistance of Cu-12.5Ni-5Sn alloy. • The corrosion resistance of Cu-Ni-Sn-xY was studied by electrochemical workstation. • The corrosion depth of the alloy with 1.0 wt% addition decreased by about 44.6 %. • Y addition promotes the uniform distribution of Ni and Sn elements. • Addition of 1.0 wt% Y alloy corrosion surface with Y 2 O 3 generation. [ABSTRACT FROM AUTHOR]

The rare earth elements are extensively incorporated in combination with alloys to fill up the demanding gaps of applications in future technologies like thermoelectrics. We give detailed prediction of electronic, magnetic, mechanical, thermoelectric, thermodynamic and optical properties of YCoTiX (X = Al, Ga, Si, Ge) quaternary Heusler alloys. The ground state properties reveal the alloys possess the LiMgPdSn-type structure with F -43 m space group. The spin polarized band structure give us a half-metallic nature at optimized lattice parameters. The minority spin band gaps are found to be indirect with calculated values as 0.53 eV for YCoTiAl, 0.61 eV for YCoTiGa, 0.71 eV and 0.62 eV for YCoTiSi and YCoTiGe, respectively. The total magnetic moment follow the Slater-Pauling curve rule of (M = Z tot – 18). Similarly, the optical properties of these alloys depict the similar behavior of electronic states near the Fermi level with substantially spins oriented along the direction of magnetization in all the alloys. The thermoelectric coefficients are investigated to infer their stand for waste heat recovery systems, where Seebeck coefficients detail their n -type behavior. Conversion efficiency is established using the dimensionless figure of merit, zT calculated as 0.75 at 550 K for YCoTiAl, 0.14 at 750 K for YCoTiGa and 0.31 at 750 K for both YCoTiSi (Ge). Thermodynamic parameters convey that all the alloys possess no anomalies with respect to phase transition or instabilities. • Predicted Heusler alloys are new class of functional materials with perfect half-metallicity. • They present robustness with respect to variation of lattice constant. • They have well established thermoelectric response over high temperature range. • They present good opto-electronic response with far-ultraviolet photo detector applications. • Anisotropic in nature, possibility of micro cracks at growing process. [ABSTRACT FROM AUTHOR]

Lightweight high-entropy alloys (LHEAs) with body-centered-cubic (BCC) structure have attracted wide attention due to their considerable strength-ductility synergy. However, the lack of work hardening ability is a key weakness, limiting the engineering application. In this study, appropriate contents of rare-earth element yttrium (Y) were added to the as-cast Ti-Zr-V-Nb-Al LHEAs with single BCC structure, and the microstructure and work hardening behavior of these LHEAs were investigated. Benefiting from the addition of Y, these LHEAs generated slight of Y-rich and Y-O-rich phases both in the grains and on the grain boundaries. During plastic deformation, these precipitates can effectively prevent dislocation slip and promote the dislocation intersections and reactions, which can improve the work-hardening ability. Moreover, adding Y can promote the large constitutional supercooling of the LHEAs and refine the grain size of the LHEAs, which also improve the work-hardening ability. Finally, the work hardening of as-cast Ti-Zr-V-Nb-Al LHEAs were successfully turned from negative to positive with 0.2 at% Y addition, with only few ductility loss. Our work provides an effective means of optimizing the mechanical properties, especially the work hardening ability, of as-cast BCC LHEAs. • Adding Y in LHEAs can refine the grain size and generate precipitated phase. • The work hardening rate were turned around from negative to positive after adding Y. • The appropriate amount of Y can well keep the considerable strength and ductility. [ABSTRACT FROM AUTHOR]

The main purpose of this paper is to study the extraction and separation of key fragment elements based on the electrolytic refining process of spent fuel dry reprocessing. Firstly, the electrochemical mechanisms of Er(III) and Yb(III) in LiCl-KCl molten salts were investigated on W and In film electrodes with applied cyclic voltammetry (CV), square wave voltammetry (SWV) and open circuit potential (OCP) at 773 K. The results indicated that the reduction behaviour of In(III) and Yb(III) ions were a two-step transfer process and Er(III) ions was a one-step transfer process. Then, the kinetic parameters in electrochemical processes were calculated on an In electrode with different temperatures. The OCP approach was used to determine the equilibrium potential of Er(III)/Er(0) in the temperature range of 773 K∼848 K, and thermodynamic parameters of the In 3 Er alloy were provided. Based on electrochemical behaviour results, the electrochemical extraction of Er(III) and Yb(III) from LiCl-KCl-ErCl 3 molten salts and LiCl-KCl-YbCl 3 molten salts at liquid In electrodes was performed by constant potential and constant current electrolysis, respectively. The electrolysis products were determined by X-ray diffraction (XRD), scanning electron microscopy and energy dispersive spectrometry (SEM-EDS), the primary intermetallic compounds generated in the alloys were In 3 Er and In 3 Yb. The average extraction rates for Er(III) and Yb(III) were 94.70% and 96.54%, respectively, according to inductively coupled plasma atomic emission spectroscopy (ICP-AES) analysis. Er(III) and Yb(III) were selectively extracted and separated from LiCl-KCl-ErCl 3 -YbCl 3 molten salts by potentiostatic control on the basis of the previously studied Lns (Er and Yb) extraction on In electrodes. The separation rate of Er(III) and Yb(III) by electrochemical selective deposition was 94.21%. • Constant potential and current electrolysis were performed to extract Er (94.70%) and Yb (96.54%) on In electrode. • Erbium and ytterbium were selective extracted and separated by potentiostatic with an average separation rate of 94.21%. • The kinetic parameters of In(III) and the thermodynamic parameter of In 3 Er were investigated by electrochemical techniques. • Potential parameters and deposition potential sequences of Er and Yb on W and In electrode are provided. • Our researching results provide theoretical basis for extraction and separation of Lns. [ABSTRACT FROM AUTHOR]

The high self-corrosion rate of the aluminum anode in the alkaline electrolyte will greatly lower the anode utilization efficiency, and therefore shorten the life of the aluminum-air battery. We discover that the self-corrosion rate of Al-0.5Mg-0.08Sn alloy anode in 4 M NaOH electrolyte can be reduced by more than 90% by alloying trace (≤0.10 wt%) Ce or Sm. After alloying trace Ce or Sm, the discharge voltage of the Al-air battery is stabilized, and the anode utilization efficiency and energy density increase by ∼100%. The reduction of self-corrosion rate arises from the precipitated phase transformation from the Mg 2 Sn phase to the Ce 5 Sn 3 phase or the Sm 4 Sn 3 phase and the microstructure homogenization. This work provides a novel method to suppress the self-corrosion of primary Al-air batteries while maintaining the discharge voltage. [Display omitted] • Self-corrosion rate was significantly reduced by more than 90%. • The anode efficiency increases by about 100%. • The discharge energy density increases to about 2000 Wh·kg−1. • The inhibition of SC arises from precipitated phase and microstructure transition. [ABSTRACT FROM AUTHOR]

The development of a better understanding of the low temperature nanophase evolution of high surface area titania (TiO 2 ) based powders is essential for their use in photocatalytic applications. A series of rare earth (RE) element doped TiO 2 powders were prepared by sol-gel processing. The effects of RE doping level, ionic size and heat treatment temperature on the nanophase structure evolution and the dopant ion location in TiO 2 main matrix were investigated. Anatase was determined to be the main phase up to 900 °C at all doping levels for all REs. Anatase to rutile phase transformation was inhibited by RE doping. The inhibitory effect of REs increased with increasing ionic radius. Oxide phases of La, Nd, Pr, Sm were not present up to 5% and Nd 4 Ti 9 O 24 phase was formed at 10% doping level at 800 °C. The formation of RE 2 Ti 2 O 7 phases were determined for the REs with relatively lower ionic radii at 800 °C. [ABSTRACT FROM AUTHOR]

The effect of Gd addition on microstructure, martensitic transformation and mechanical properties of Ni 50 Mn 36 Sn 14 ferromagnetic shape memory alloy has been investigated. The results show that Gd addition leads to some changes in the microstructure and crystal structure. Martensitic transformation is observed in Ni 50 Mn 36 Sn 14 alloys with adding different amount of Gd. The compressive strength and compressive strain of alloys is notably enhanced with the increase in Gd content. The compressive strength increases from 448 MPa to 707 MPa and the compressive strain increases from 4.5% to 9.0% with increasing Gd content from 0 at.% to 2 at.%. The mechanism of the improved mechanical properties is also revealed. [ABSTRACT FROM AUTHOR]

Ce-doped GaN single-crystalline nanowires were synthesized by a two-step approach that involved a chemical vapor deposition (CVD) growth of pure GaN nanowires and a post-sintering treatment for the incorporation of Ce ions. The structural, morphological and compositional characterizations revealed that Ce ions have been uniformly introduced into the lattice of wurtzite-structured GaN nanowires without the degeneration of morphology and crystallinity. PL spectra of the samples show the near-band-gap emissions with obviously shifts that depend on the post-sintering durations. [ABSTRACT FROM AUTHOR]

High-entropy alloys (HEAs) with nanoscale crystal structure have supposed to be good microwave absorbers due to their excellent soft magnetic properties. Annealing is typically employed to optimize microwave absorption, however, grain coarsening motivated by temperature will lead to serious deterioration of soft magnetic properties. Herein, we introduce the rare earth (RE) element Gd into FeCoCrAlGd x (x = 0, 0.1, 0.2, 0.3) HEAs, which is expecting to inhibit the nanograin coarsening through dispersing Gd 2 O 3. The incorporation of Gd results in a low coercivity (H c), high saturation magnetization (M s), and high complex permeability (μ′ and μ″) of the HEAs. Especially, the H c for as-annealed FeCoCrAlGd 0.2 (114 Oe) is only 60.6 % of that for as-annealed FeCoCrAl (188 Oe). Owing to the remarkable magnetic properties, all Gd-doped HEAs have a larger effective absorption bandwidth at lower thicknesses. The reflection loss (RL) of as-annealed FeCoCrAlGd 0.1 reaches a maximum absorption of −45 dB and an effective absorption bandwidth of 5 GHz (thickness is 1.5 mm). In addition, DFT (density functional theory) calculations are performed to analyze the energies and magnetic moments of the systems. This article provides guidance for design of high performance soft magnetic microwave absorbers. • Coarsening behavior of nanograins during annealing is suppressed by dispersed Gd 2 O 3 particles. • Gd-doped high-entropy alloys have significantly lower coercivity and higher saturation magnetization. • Static magnetic properties induce higher complex permeability and excellent microwave absorption. • The energies and magnetic moments of the systems were calculated by density functional theory (DFT) calculations. [ABSTRACT FROM AUTHOR]

The first reported microstructural study of Mg-RE alloy matrix composites in the semi-solid state was presented. Mg–Nd–Zn (ZM6) alloy matrix composites reinforced with SiC particles were fabricated by mechanical stir casting and extrusion. Semi-solid slugs of SiC p /ZM6 composites were prepared by semi-solid thermal transformation (SSTT) route and recrystallization and partial melting (RAP) route, respectively. The microstructure evolution of as-cast and as-extruded SiC p /ZM6 composites during semi-solid remelting was examined under the same conditions. The coarsening mechanisms of SSTT and RAP composites were discussed. The results show that the microstructures of RAP SiC p /ZM6 composites consist of fine and spheroidal solid grains surrounded by intergranular liquid, while the SSTT composites consist of inferior microstructures with coarse solid grains and high proportion of intragranular liquid droplets. The solid grain coarsening during partial remelting is dominated by coalescence and Ostwald ripening for SSTT and RAP SiC p /ZM60 composites, respectively. The formation of intragranular liquid droplets and entrapped SiC particles were also discussed. [ABSTRACT FROM AUTHOR]

The magnetocaloric effect of (Fe 0.71 RE 0.05 B 0.24 ) 96 Nb 4 (RE = Tb, Ho and Tm) bulk metallic glasses (BMGs) of diameters up to 6.5 mm were attained by 4.8 at.% RE alloying. The Curie temperature ( T C ) of Tm doped alloy, being the highest among these alloys, deviates from typical relationship between T C and de Gennes factor. Its unique electronic structure has been suggested to attribute to the observed trend. Furthermore, Tm doped alloy presents the largest peak magnetic entropy change ( | Δ S M pk | ) of 1.21 J kg −1 K −1 for an applied field of 1.5 T, which compares favorably with those of other Nanoperm-type alloys. The phenomenological universal curve for Δ S M demonstrates that alloys exhibit similar critical exponents at T C . This family of heavy RE doped Fe-based BMGs is potential candidate used as bulk magnetic refrigerants with the final required shapes. [ABSTRACT FROM AUTHOR]

Additively manufactured superalloys have attracted increasing attention due to their inherent hierarchical microstructure, but have been impeded by anisotropic properties originating from columnar grains. In this work, we present a strategy for inhibiting the formation of columnar grains in which 0.3 wt% scandium (Sc) was introduced as an oxide dispersion strengthener (ODS) into the Inconel 718 (IN718) alloy fabricated via laser powder bed fusion (LPBF). The effects of Sc on the microstructure and mechanical properties of the IN718 were investigated, revealing the in-situ formation of Sc 2 O 3 nanoparticles as well as the cellular sub-grains microstructure with high-density of dislocations into the as-prepared IN718-Sc alloy. The addition of Sc disrupted the typical columnar grains generated by the LPBF process, resulting in, the strong (100) texture in pure IN718 alloy changing to the irregular orientation in IN718-Sc alloy. In addition, the average grain size and the aspect ratio also show decreases when Sc introduction. As a result, the as-designed IN718-Sc alloy achieved a higher yield strength of 1030 MPa at room temperature and 837 MPa at 650 ºC, respectively, which can be attributed to Zener pinning of grain boundaries by dispersed Sc 2 O 3 nanoparticles. Importantly, the insight into dispersing oxide particles to regulate microstructure and improve properties in this study could provide guidance for other alloy fabrication through powder additive manufacturing. • Generating in situ rare earth oxides as nucleating agent, the columnar grains trend was suppressed. • With Sc addition, the grain size was refined and Sc 2 O 3 was generated to pin dislocation. • IN718-Sc exhibited a 20% increase in yield strength at room temperature and high temperature. [ABSTRACT FROM AUTHOR]

Highlights: [•] MnFeW11 with Keggin structure was synthesized for the first time. [•] K0.57WO3 tungsten bronze is the main production in the permeated sample. [•] The electrical conductivity increases by approximately 1000 times after permeation. [•] The present work provides a new method for solid electrolyte conducting materials. [Copyright &y& Elsevier]

Abstract: The effects of partial substitution of rare earth Dy for Ga on the mechanical and magnetic properties of Mn-rich Ni50Mn29Ga21−x Dy x (0≤ x ≤5) ferromagnetic shape memory alloys were investigated in detail. The results show that an appropriate amount of Dy addition significantly improves the mechanical properties of Ni–Mn–Ga alloy. With an increase in Dy content, the compressive strength enhances rapidly at first and then becomes stable when the Dy content is more than 1at.%. However, the compressive strain increases dramatically and reaches a maximum value with 1at.% Dy addition. Further increase in Dy content makes the compressive strain of the alloys decrease gradually. The mechanism of the improved mechanical properties is also discussed. Moreover, Dy doping changes the fracture type from intergranular fracture of Ni–Mn–Ga alloy to transgranular cleavage fracture of Ni–Mn–Ga–Dy alloys. The Curie temperature remains almost unchanged at low Dy content and subsequently decreases. [Copyright &y& Elsevier]

Abstract: Samples of pure and rare earth (RE)-doped nanocrystalline Zn2TiO4 (RE=Eu, Er, Tm) have successfully been prepared by the single batch sol–gel method in a form of powders. The powders were annealed up to 1200°C and analyzed by DTA and XRD methods. Sizes of formed nanocrystals were calculated from the Scherer equation and verified by the SEM analysis. Activation energies of crystallization were calculated using the Kissinger, Ozawa and Augis–Bennett approximations and reaction mechanisms were proposed evaluating the Avrami exponents from the Johnson–Mehl–Avrami equation. It has been found that RE elements particularly substitute zinc ions in the crystal lattice and are fully soluble up to 0.5at.% related to the some of cations. Furthermore, the results have shown that the presence of RE elements blocks the crystallite growth and supports the nucleation process leading to the formation of smaller and more uniform nanocrystals compared to the undoped Zn2TiO4. [Copyright &y& Elsevier]

Abstract: We investigated the effects of adding small amounts of cerium (Ce) to low Ag content Sn solder (Sn–1.0wt.%Ag) on melting temperature, microstructure, wettability and mechanical properties using differential scanning calorimeter, optical microscope, scanning electron microscope, energy dispersive X-ray spectroscopy, wetting balance tester, Vickers hardness tester and tensile tester assays. The addition of Ce had little influence on the melting behavior of Sn–1.0Ag solder, but improved its wettability, mechanical properties, and microstructure. [Copyright &y& Elsevier]

Abstract: Mechanochemical decomposition by milling a mixture of monazite and sodium hydroxide powder and subsequent leaching by sulfuric acid for the extraction of rare earth elements at room temperature has been investigated. The milling of the mixture allows the mechanochemical formation of rare earth hydroxides and sodium phosphate as milling progresses. Nearly all the monazite is decomposed within 120min under the present milling conditions. A 0.05N sulfuric acid solution enables us to improve the yield of each of La, Nd and Sm to around 85% or more in the powder milled for 120min. Also, respective Ce and Pr yields of about 20% and 70% remain un-dissolved since they are changed into oxide forms during and after the milling operation. These rare earth oxides are mostly dissolved as the acid concentration increases to 5N. The yield of rare earth elements increases with increasing milling time. Thus mechanochemical milling plays a significant role in achieving high yield of rare earth elements from the leaching of the milled powder. [Copyright &y& Elsevier]

Abstract: Although solders doped with rare earth elements have been reported to show many beneficial effects, tin whisker growth has been observed to grow at an extremely high rate on the surface of such novel solder alloys. This study shows that adding 0.5wt.% Ge into a Sn–3Ag–0.5Cu–0.5Ce alloy effectively decreased whisker growth. This inhibition effect is attributed to alleviation of oxidation in the CeSn3 intermetallic phase in this alloy as a result of Ge-alloying. Compressive stress in this case is insufficient to extrude tin atoms out of the solder to form whiskers. [Copyright &y& Elsevier]

Abstract: Samarium (Sm) additions to as-cast Mg-5Al-3Ca-based alloys result in changes, such as equiaxed grains and a refined grain size. The microstructure of as-cast Mg-5Al-3Ca-xSm alloys consists of an α-Mg matrix, a (Mg, Al)2Ca eutectic phase, and an Al2Sm intermetallic compound. In as-cast alloys, the (Mg, Al)2Ca eutectic phase was located at grain boundaries with a chain structure, and the Al2Sm intermetallic compounds were homogeneously distributed at the α-Mg matrix and grain boundaries. The eutectic phase of the extruded alloys was elongated in the extrusion direction and crushed into fine particles because of severe deformation during hot extrusion, and the grain size was refined with an increased amount of Sm addition. The maximum values of the yield strength and tensile strength were 313MPa and 330MPa at 2wt%Sm alloy content, respectively. [Copyright &y& Elsevier]

Abstract: As modification of Cu–Zn–Al shape memory alloys (SMAs), the characteristics of Cu–Zn–Al alloys containing different amount of rare earth Gd addition are investigated by optical microscopy, scanning electron microscopy (SEM), X-ray diffraction (XRD) and the bending method. The results show that Gd addition refines the grains of Cu–Zn–Al alloys obviously, and there are small spherical Gd-rich phases precipitated in the matrix of the alloys. There is no effect of Gd addition on the martensitic transformation type martensitic transformation temperatures of Cu–Zn–Al alloys. The shape recovery ratio is evidently improved with Gd addition, and the shape memory effect of Cu–Zn–Al alloy is the best when the content of Gd is between 0.08 and 0.12wt.%. [Copyright &y& Elsevier]

Abstract: The permeation of the rare earth element gadolinium (Gd) to the heteropoly compound Na2K3CuV(OH2)W11O39·16H2O using the rare earth gas phase-heated diffused permeation method is reported for the first time. Inductively coupled plasma (ICP) and X-ray photoelectron spectroscopy (XPS) were used to determine the percentage composition of the rare earth element Gd in a permeated sample. Structures of compounds before and after permeation were investigated by infrared spectroscopy (IR) and X-ray diffraction (XRD). The results show that compound anions before permeation have the Keggin structure, while the Keggin cage structure is destroyed and a new compound is produced due to the permeation of Gd. Conductivity of compounds before and after permeation was investigated by ac impedance spectra. It reveals that conductivity of the permeated sample is greatly enhanced compared with the original sample. The thermal analysis result indicates that the thermostability of the permeated sample is improved. [Copyright &y& Elsevier]

Abstract: The aim is to investigate the influence of heavy rare earth Gd addition on the microstructure, martensitic transformation and mechanical properties of polycrystalline Ni50Mn29Ga21 shape memory alloy. It is shown that microstructure of the Ni–Mn–Ga–Gd alloys consists of the matrix and the Gd-rich phase. The Gd-rich phase firstly disperses homogeneously in the matrix with small amounts and then tends to segregate at the grain boundaries with the increase of Gd substitution for Ga. With increasing Gd content, the martensitic transformation temperatures increase remarkably and the grain size is reduced obviously. Different martensitic phase transformation appears in different Gd content. Martensite structure changes from 5M with 0.1at% Gd to 7M when the content of Gd is more than 0.1at%. It is revealed that the addition of Gd significantly enhances the bending strength and improves the ductility of the alloys. The mechanism of the improved mechanical properties is also discussed. [Copyright &y& Elsevier]

Abstract: The eight compounds of R–Rh–B (R=Er, Gd) system have been studied by 166Er and 155Gd Mössbauer spectroscopy and DC magnetization measurements. Mössbauer spectroscopy revealed the bonding properties, charge distribution around the nucleus of the rare earth elements and the magnetic properties. Magnetic study has been done first for ErRh2 and ErRh5. [Copyright &y& Elsevier]

Abstract: Ba2(In1−x R x )2O5 (x =0, 0.05, 0.1; R=Sc, Lu, Yb, Y, Dy, Gd, Sm) were synthesized by a solid-state reaction method, and all the prepared samples were confirmed to be a single phase by XRD. The lattice volume increased with increasing ionic radius of the substituents, and the slope in the plot of the lattice volume against the ionic radius was changed around the ionic radius of Y3+ or Dy3+. The order–disorder transition temperatures of oxygen vacancies of all the prepared samples were determined by electrical conductivity measurement. The transition temperatures of the samples substituted by larger (or smaller) ions in the ionic radius than In ion were larger (smaller) than that of un-substituted Ba2In2O5, probably due to the preferred site of substituent to either octahedral InO6 site or tetrahedral InO4 site. [Copyright &y& Elsevier]

Abstract: Thermal expansions of (U,Dy)O2 solid solutions were investigated between room temperature and 1673K by using a thermo-mechanical analyzer. The lattice parameter of (U,Dy)O2 pellets is lower than that of UO2 and it decreases as Dy content increases. The linear thermal expansion and average thermal expansion coefficients of (U,Dy)O2 are higher than that of UO2. For the temperature range from room temperature to 1673K, the average thermal expansion coefficient values for UO2 and (U0.8Dy0.2)O2 are 10.97×10−6 and 11.37×10−6 K−1, respectively. [Copyright &y& Elsevier]

In this research work, the new kind of 6111Al matrix composites reinforced by nanosized ZrB 2 particles and rare earth element Y have been successfully prepared via the Al-KBF 4 -K 2 ZrF 6 -Y in situ reaction system in the melt. Compared to the traditional particle reinforced aluminum matrix composite, this innovative fabrication system broke through the limit in the content of reinforcing phases and helped to modify the morphology and distribution of in situ ZrB 2 particles with assistance of Y addition. The results of tensile testing on 6111Al-3 wt%ZrB 2 -0.3 wt%Y composites revealed that the YS, UTS and elongation reached to 295 MPa, 325 MPa and 13.2%, which have been increased by 28.2%, 19.5% and 83.3% respectively compared to the matrix alloy. The distribution state and morphology of reinforcing phases including in situ ZrB 2 particles, Al 3 Y and Y 5 Si 3 precipitates were analyzed by the latest equipments like X-ray diffraction (XRD), Optical microscope (OM), Scanning electron microscope (SEM) and High resolution transmission electron microscope (HRTEM) equipped with Energy dispersive spectroscope (EDS). • Properties of 6111Al improved a lot by cooperation of Y and ZrB 2 particles. • Y modifies the distribution and morphology of ZrB 2 particles. • The synergistic strengthening mechanism of Y and ZrB 2 particles are discussed. [ABSTRACT FROM AUTHOR]

The corrosion behaviour of Mg-0.3Ce, Mg-0.41Dy, Mg-0.63Gd, Mg-1.44Nd and Mg-1.43La (wt.%) alloys in 3.5 wt% NaCl solution was investigated using electrochemical tests. The as-cast microstructures of the Mg-RE alloys were characterized by the presence of second phases (Mg x Ce, Mg 41 Dy 5 , Mg 12 Gd, Mg 12 Nd, Mg 41 Nd 5 , Mg 24 Nd and Mg 12 La) with different volume fraction and distribution. Results show that the corrosion mechanism was altered from uniform to localized corrosion mechanism depending on the specific RE alloying elements. The corrosion resistance of the Mg-RE alloys is increasing in the following order: Mg-1.43La, Mg-1.44Nd, Mg-0.3Ce, Mg-0.63Gd and Mg-0.41Dy. Accordingly, the corrosion morphology in the best resistant Mg-0.41Dy alloy and the worst Mg-1.43La alloy were observed and compared after 2h and 24 h of immersion using SEM-EDS, XPS and XRD analysis. The formation of the Dy 2 O 3 oxide prevents the Mg-0.41Dy alloy from pitting corrosion and lead to an excellent corrosion surface even after 24 h of immersion. Meanwhile, the presence of a high fraction of the Mg 12 La phase along the grains boundaries in the Mg-1.43La alloy causes severe pitting corrosion by acting as anodic phase. • The corrosion behaviour of Mg-RE alloys was largely influenced by RE addition element. • The corrosion resistance increases in the order: Mg-1.43La, Mg-1.44Nd, Mg-0.3Ce, Mg-0.63Gd and Mg-0.41Dy. • A uniform corrosion film composed of Mg(OH) 2 and Dy 2 O 3 formed on Mg-0.41Dy alloy. • The Mg 12 La phase is the main causes of the poor corrosion resistance of the Mg-1.43La alloy. [ABSTRACT FROM AUTHOR]