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ZnO:Al (AZO) transparent conductive films used for solar cells were prepared by DC magnetron sputtering technology. The influence of substrate temperature on the electrical and optical properties of the films was studied. Further, the AZO films prepared were etched in diluted hydrochloric acid. The film surface morphology after etching for different time was researched.

In this paper, we investigated indium-tin-oxide (ITO) thin films on glass substrates deposited by RF magnetron sputtering using ceramic target to find the optimal condition for fabricating optoelectronic devices. The structural, electrical and optical properties of the ITO films prepared at various substrate temperatures were investigated. The results indicate the grain size increases with substrate temperature increases. As the substrate temperature grew up, the resistivity of ITO films greatly decreased. The ITO film possesses high quality in terms of electrode functions, when substrate temperature is 480°C. The resistivity is as low as 9.42 × 10^-5 Ω•cm, while the carrier concentration and mobility are as high as 3.461 × 10²¹ atom∕cm³ and 19.1 cm²∕V⋅s, respectively. The average transmittance of the film is about 95% in the visible region. The novel ITO/np-Silicon frame, which prepared by RF magnetron sputtering at 480°C substrate temperature, can be used not only for low-cost solar cell, but also for high quantum efficiency of UV and visible lights enhanced photodetector for various applications.

CrCuN films were deposited under different substrate temperatures by direct current (DC) magnetron sputtering. The structure and wear resistance of the films were then studied. The substrate temperature has almost no effect on the film composition, phase constitution and preferred orientation. The CrCuN films have 3 at.% Cu and consist of CrN phases with CrN(200) preferential growth independent of the substrate temperature. But a strong effect of the substrate temperature on the wear behavior is noticed. The film prepared under the substrate temperature of 100°C has the best wear performance. Its friction coefficient and wear rate are 0.1 and 6.6 × 10^-6 mm³/Nm, respectively.

We prepared the pulsed laser deposited Fe:LaSrFeO₄ (LSFO) composite films on quartz substrates by decomposing the La${}_{0.5}$Sr${}_{0.5}$FeO₃ target at room temperature in a high vacuum. Impacts of anneal temperature on the structural and physical properties have been investigated, and the systematic changes were found in structural, magnetic and optical absorption properties upon annealing. The LSFO (110) spacing decreases with the increase of annealing temperature, which can be attributed to the release of intrinsic strain; and there is an increase in spacing for the 750${}^{\circ }$C annealed sample, which is ascribed to the oxygen loss in LSFO films.

Ni–TiN thin films with different TiN nanoparticle contents were successfully fabricated from a nickel bath with the addition of four TiN nanoparticles loadings (2, 4, 6 and 8g/L). The influence of the TiN nanoparticle content on the film structure, micro-hardness, micro-strain and residual stress was examined, and the film wear behavior was investigated in detail. The results showed that the average size of the nickel grains and TiN nanoparticles is 68.1nm and 22.6nm, respectively, for the film deposited with 8g/L TiN. X-ray diffraction patterns indicated that the film deposited with 2g/L TiN displays the (2 0 0) preferred orientation; however, when the concentration of TiN in the bath was increased to 6g/L, such orientation was suppressed and a random arrangement showed up. The film wear loss gradually decreases as the concentration of TiN additive in the bath increases from 2g/L to 8g/L, and a minimum loss of approximately 39.7mg was obtained for the film deposited at 8g/L TiN, which also displayed the maximum average micro-hardness (789.4HV).

As the phenomenon of fatigue damage is a common failure mode of equipment, the reliability evaluation and life prediction have become a hot-spot. The precise prediction of fatigue life in the initiation stage has become necessary. The common prediction study for structural fatigue life takes less influence factors into consideration. The common prediction results of fatigue life cannot be quantitatively corrected by the influence factors at the same time. This paper presents a research on the prediction approach for structural fatigue life based on the multi-factor correction. The influence of some factors on the fatigue life was analyzed and the prediction approach for structural fatigue life based on multi-factor correction was raised. Then the fatigue life of axle housing was predicted by using the corrected approach, as the case study. Moreover, the result predicted by the local stress–strain approach and the experimental data were used to verify the accuracy of the corrected approach. It can be clearly demonstrated by the results that the corrected prediction approach can be used to achieve the precision fatigue life for engineering structures. Further, it is also a prediction approach endowed with engineering application prospects.

Ni thin films have been electrodeposited on $n$-Si (100) substrates for different deposition times at a fixed potential of 2V. The as-elaborated films have been characterized by Rutherford backscattering spectroscopy (RBS), X-ray diffraction (XRD), atomic force microscopy (AFM) and vibrating sample magnetometry (VSM). From RBS spectra, we have extracted the Ni film thicknesses, $t(\mathrm{\text{nm}})$, which ranges from 105 nm to 710 nm. The analysis of XRD spectra shows the existence of a strong $⟨$111$⟩$ texture for all film thicknesses. The strain values ${\epsilon }^{hkl}$ are negative for all Ni films indicating that they are under compressive stresses. The grains size, $〈D(\AA )〉$, increases to reach a maximum for $t=465$nm then decreases again with increasing $t$(nm). From AFM images, we have shown that the films become progressively smoother with increasing thickness. We have shown that the coercive field measured in parallel geometry, $H_{C||}$, increases with increasing thickness.

The effect of iron content on the structure, morphology and magnetic properties of (Ni${}_{60}$Co${}_{40}$)${}_{100-}$${}_x$Fe${}_x$ powders synthesized by hydrothermal method has been studied. Several samples have been elaborated for different Fe content ($x$= 0, 3, 5, 7, 10 and 13.5). The as- prepared samples have been characterized by X-ray diffraction (XRD), Scanning Electron Microscopy (SEM) and Vibrating Sample Magnetometry (VSM). From XRD spectra and for all Fe content, we have shown the presence of both face centered cubic (FCC) and Hexagonal (HCP) nanosized phases. The lattice parameter increases with increasing Fe content and the grains size varies with Fe content to reach a minimum value of 32 nm for (Co${}_{40}$Ni${}_{60}$)${}_{90}$Fe${}_{10}$. From hysteresis curves, we have extracted the saturation magnetization, Ms, and the coercivity, Hc. We noticed that Ms increases and then decreases as a function of Fe content. The values of Hc vary from 156 Oe to 186 Oe depending on the particles shape.

In this review, the crystal structure and the synthesis of the sodium potassium niobate (K_0.5Na_0.5NbO₃) as a promising candidate for lead-free piezoelectrics are addressed. The sintering and the microstructure as prerequisites for obtaining ceramics with reliable and sufficiently high piezoelectric properties for selected applications are discussed.

Fe₂SiS₄ and its composite with porous carbon from carbonization of PAN porous carbon (PC) were synthesized using one-pot method, which were characterized by XRD, SEM, TEM, XPS and Raman spectrum techniques. Their electrochemical data as anode materials for lithium-ion batteries were firstly studied. The results indicate that the Fe₂SiS₄ particles dispersed on the surface or in the pores of PC has the 1st capacity of 961.9mAh/g, and around 400mAh/g capacity can be still maintained after 50 cycles at 0.2C, much enhanced electrochemical performance than those for pure Fe₂SiS₄.

Lead–free Sr${}_{1-x}$Ca_xTiO₃ ($x=0,0.4$) ceramics were synthesized via a solid state reaction technique at room temperature. The effects of ionic substitutions in A-sites between strontium and calcium on the structural and dielectric properties were investigated. XRD technique was used to identify the crystal structure and to demonstrate the phase purity. SEM observations have shown homogeneous morphologies for all samples. Dielectric measurements were investigated for a wide range of frequency (100Hz–1GHz) and temperature (25${}^{\circ }$C–250${}^{\circ }$C). Strontium substitution by calcium has not only led to a decrease in the dielectric permittivity value, but also to the loss tangent value by a considerable factor. Interesting values of the quality factor and the quite constant value ${\epsilon }^{\prime }\sim 200$ in extended frequency and temperature ranges show that SCT ceramic could be a real candidate for the development of monolithic ceramic capacitors dedicated to high-frequency lead-free components and/or to extremely high-temperature environments.

The experimental data of electrodeposition kinetics researches and structure formation of ternary CoNiFe alloys deposited onto low-carbon steel 08kp in the presence of X-rays are presented. Relations of deposit rate, current efficiencies, element and phase compositions of CoNiFe coatings formed from sulfate baths with respect to cathode current densities (0.5–3A/dm${}^2)$, electrolyte composition and irradiation were obtained. It is shown that, the CoNiFe coatings deposited by the electrochemical method involving exposure of the X-rays are characterized by more perfect morphology surfaces with less developed surface geometry than reference coatings. The effect of the X-ray irradiation on the electrodeposition of CoNiFe coatings promotes formatting of alloys with increased electropositive component and modified phase composition.

Envisaged through adding sintering additives to achieve low-temperature sintering preparation, in order to overcome the volatilization of sodium ions and potassium ions in the high-temperature preparation, so as to improve the density and electrical properties of KNN-based piezoelectric ceramics. This research uses traditional solid-state sintering technology, a high density, high properties lead-free piezoelectric ceramics, KNNSC-$x$, successfully prepared with sintering additives CuO. The modern test analysis of XRD and SEM shows that a moderate amount of CuO doped in the range of research can form a single perovskite structure of an orthorhombic structure, not found in any second phase, and can promote grain evenly growing and improve the sintering properties of KNN-based piezoelectric ceramics. The KNNSC-0.04 ceramics exhibit excellent electrical properties through various electrical tests such as $d_{33}$ = 238pC/N, $k_p$= 47%, ${𝜀}_r$= 1049, tan$\delta$= 2.4%, $P_r$ = 25.6 $\mu$C/cm², $E_C$ = 1.24 kV/mm, respectively. These test results show that the KNNSC-$x$ piezoelectric ceramics have great potential to be applied in middle- and low-voltage piezoelectric devices.

Temperature dependent X-ray diffraction (XRD) and dielectric properties of perovskite Ba(Zr${}_{0.2}$Ti${}_{0.8})$O₃ ceramic prepared using a standard solid-state reaction process is presented. Along with phase transitions at low temperature, a new phase transition at high temperature (873${}^{\circ }$C at 20Hz), diffusive in character has been found where the lattice structure changes from monoclinic (space group: $P2∕m)$ to hexagonal (space group: $P6∕mmm$). This result places present ceramic in the list of potential candidate for intended high temperature applications. The AC conductivity data followed hopping type charge conduction and supports jump relaxation model. The experimental value of $d_{33}=98$pC/N was found. The dependence of polarization and strain on electric field at room temperature suggested that lead-free Ba(Zr${}_{0.2}$Ti${}_{0.8})$O₃ is a promising material for electrostrictive applications.

This paper throws light on the preparation of transition metal-doped Mg${}_{0.5-x}T{M}_x$Zn${}_{0.5}$Al₂O₄ ($x=0$, 0.05 and $TM=\mathrm{\text{Co}}$, Ni, Cu) aluminates via solid-state reaction route. The X-ray diffraction characterization analysis confirmed that all the samples have crystallized into the psuedocubic phase having space group Fd3$m$ and were single phased. The incorporation of transition metals viz. Co${}^{2+}$, Ni${}^{2+}$, Cu${}^{2+}$ in the Mg${}_{0.5}$Zn${}_{0.5}$Al₂O₄ matrix does not result in the appearance of new peaks or any considerable shift in diffraction peaks within the limits of XRD experimentation. This infers homogeneous dispersion of dopants at the Mg-site which is attributed to nearly same ionic radii of the dopants to that of Mg-site in Mg${}_{0.5}$Zn${}_{0.5}$Al₂O₄. Lattice structure, bonding nature and hence the spinel formation were verified through Raman scattering technique. The compositional verification was carried out via energy dispersive analysis of X-rays (EDAX). The surface morphology and hence the microstructural studies were carried out using field emission scanning electron microscopy (FESEM). The synthesized Mg${}_{0.5-x}T{M}_x$Zn${}_{0.5}$Al₂O₄ ($x=0$, 0.05 and $TM=\mathrm{\text{Co}}$, Ni, Cu) aluminate samples were tested for polarization studies keeping their insulating nature into consideration and they displayed a sign of well-behaved P-E loop.

The preparation of ${\text{La}}_{0.9}$${\text{Na}}_{0.1}$CrO₃ (LNCO), ${\text{Ni}}_{0.5}$${\text{Cu}}_{0.5}$Fe₂O₄ (NCFO) and their composites of the type $(1-x)$${\text{La}}_{0.9}$${\text{Na}}_{0.1}$CrO₃ (LNCO) $+$ ($x$) ${\text{Ni}}_{0.5}$${\text{Cu}}_{0.5}$Fe₂O₄ (NCFO) $(x=0.25$, 0.50$)$ through solid state route is reported. From X-ray diffraction data analysis, the parent ${\text{La}}_{0.9}$${\text{Na}}_{0.1}$CrO₃ was found to crystallize in orthorhombic structure (Pnma) while ${\text{Ni}}_{0.5}$${\text{Cu}}_{0.5}$Fe₂O₄ has crystallized into the cubic structure (Fd3$m$) further verified via Retvield refinement. The morphology and compositional studies were carried out using field emission scanning electron microscopy (FESEM) and energy dispersive analysis of X-rays (EDAX), respectively. Lattice structure was confirmed via Raman characterization for the prepared samples. The sample formation was further verified through Fourier transform Infra-Red (FTIR) spectroscopy. The dielectric studies reveal the ${\text{La}}_{0.9}$${\text{Na}}_{0.1}$CrO₃$(13*10^4)$ and ${\text{Ni}}_{0.5}$${\text{Cu}}_{0.5}$Fe₂O₄$(1.83*10^4)$ exhibit high dielectric constant. However, their composites show abrupt drop in dielectric constant. The electric modulus study confirmed that the samples exhibit non-Debye character with spread of relaxation time constants.

The results of a comprehensive study of the crystal structure, grain structure, and strength properties of ceramic bismuth ferrite with rare earth elements (REE) obtained by two-stage solid-phase synthesis followed by sintering using conventional ceramic technology are presented. The reasons for the formation of low mechanical strength and the development of destruction phenomena in solid solutions with small REE ($\bar{R}<0.94$ Å) are considered: Tb, Dy, Ho, Er, Tm, Yb, Lu. The causes of the observed phenomena associated with the composite-like structure of the studied media and, as a consequence, the occurrence of local stresses of structural elements that provoke crack formation are established. A source of the latter are also the structural features of the grain landscape. The conclusion is made about the appropriateness of taking into account the information obtained when developing devices based on BiFeO₃/REE multiferroics.

X-ray diffraction studies of synthesized Ba₂TiSi₂O₈ have shown that this compound has a fresnoite structure and is characterized by a polar phase $P$4bm at room temperature. The synthesis of Pb₂TiSi₂O₈ in the fresnoite phase under the selected synthesis conditions has led to the formation of a perovskite tetragonal phase $P$4mm corresponding to PbTiO₃.

This paper presents the results of studies of the structure, microstructure, dependences of the piezoelectric properties on the electric field (dielectric hysteresis loops, reversible nonlinearity, deformation characteristics) and dielectric properties of the ceramic material PCR-13 (based on the PZT system) in the temperature range 300–900K and frequencies of an alternating electric field ($25÷2\cdot 10^6$) Hz. The character of the obtained dependences made it possible to attribute PCR-13 to ferro-hard materials. Using the HF cathodic sputtering method, PCR-13 thin films were fabricated on Si (001) substrates. It is shown that they are polycrystalline textured, while in comparison with bulk material, the film contains tensile stresses of the unit cell in the plane of the substrate and compresses in the perpendicular direction with the value ${\epsilon }_{33}=-0.018$. The capacitance-voltage characteristics of the Al/PCR-13/Si/Al heterostructure were studied. The reasons for the revealed patterns are discussed.

Vinylidene fluoride-trifluoroethylene copolymer films of molar ratio 70/30 with thickness of about 1 $\mu$m have been deposited from solution in ethyl methyl ketone to a glass substrate with an aluminum electrode by spin coating. The solution has been filtrated through a PTFE membrane filter with pore size 0.2 $\mu$m directly before spin coating or it has been used as is (unfiltrated). After deposition of a top electrode, the samples have been polarized by hysteresis loops with an electric field amplitude of about 100 V/$\mu$m. In samples, annealed at temperature 145${}^{\circ }$C for 3 h, a high remanent polarization of about 7.5 $\mu$C/cm² has been achieved, without significant differences between samples fabricated of filtrated or unfiltrated solution. Spherulitic lamella are growing in films fabricated of filtrated solution when they are heated above the melting temperature to 159${}^{\circ }$C for 3 min before the further annealing process at 145${}^{\circ }$C. These films show substantially lower remanent polarization below 4 $\mu$C/cm². Pyroelectric images recorded with a pyroelectric laser scanning microscope show that the spherulites have very small pyroelectric activity, i.e., the spherulites consist of flat-on lamella. In contrast, no spherulitic lamella are growing in films fabricated of unfiltrated solution heated above the melting temperature, melted and annealed under the same conditions. An explanation for this observation is that filtrating changes the structure of the copolymer in solution from polymer coil to rod. Copolymer rods deposited on a substrate will crystallize in flat-on lamella when heated above the melting temperature, in contrast to copolymer coils which crystallize in edge-on lamella.