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Uranium Laves phase UTi2 does not exist in a pure form, but can be stabilised by the presence of hydrogen, which can be absorbed in concentration exceeding 5 H atoms/f.u. Low temperature specific heat, magnetic susceptibility, and resistivity indicate that UTi2H5 is a spin fluctuator close to the verge of magnetic ordering. Its susceptibility follows at high temperatures the Curie–Weiss law with U effective moment µeff[ = 3.1 µB/U and paramagnetic Curie temperature Θp = −200 K. The temperature dependence of specific heat exhibits a pronounced and weakly field dependent upturn in Cp/T versus T below 10 K reflecting the effect of spin fluctuations. It can be described by an additional T½ term. The Sommerfeld coefficient γ = 256 mJ/mol K2 classifies the compound as a mid-weight heavy fermion. Spin fluctuations are affecting also electrical and thermal transport and thermoelectric power, which all resemble UAl2. A lattice anomaly at ≈ 240 K, attributed to the melting of hydrogen sublattice, refl...

The 57Fe enriched almost single-phase perovskites Pb(Fe0.5Nb0.5)O3 (PFN) and Ba(Fe0.5Nb0.5)O3 (BFN), prepared by a ceramic method (solid-state synthesis), were studied by Mossbauer spectroscopy, nuclear magnetic resonance (NMR), conventional and synchrotron X-ray powder diffraction (XRD). The temperature dependences of hyperfine and structural parameters of PFN, BFN from 4.2 K to temperatures above ferroelectric ordering of PFN (TS ∼ 375 K), with attention to the values of magnetic and structural transitions, were obtained. The antiferromagnetic magnetic ordering transitions were found under the Neel temperatures TN ∼ 167(3) K and 32(2) K for PFN and BFN, respectively. The spin-glass transition was at TG ∼ 10(3) K and 20(5) K for PFN and BFN, respectively. In PFN sample a small change of structural parameters around TN and structural change from trigonal to cubic structure at T ∼ 400 K was observed by XRD. The temperature dependence of XRD shows stable cubic structure in the temperature range from 4.2 K to 530 K for BFN. From Mossbauer and NMR spectroscopies it is found that both structures have perturbed environments for Nb and Fe. However, in case of PFN the low values of transferred hyperfine fields disfavour random Fe/Nb arrangement and allow proposing a picture of Fe/Nb arrangement.

Controlled synthesis of core@shell nanoparticles (NPs) for certain applications is a difficult challenge in many nanotechnology projects. In this report, a conventional arrangement composed of a gas aggregation source (GAS) is employed to generate the core NPs, which are subsequently coated by the shell materials in a secondary planar magnetron sputtering. The important difference to the usual system is the application of the two opposing planar magnetrons in a closed field configuration. The prepared core Ag NPs by a GAS are coated/treated by the two magnetrons with Ti targets. Our findings clearly show that the shell thickness can be controlled by tuning the power delivered to the secondary magnetron plasma. Characterizations of the prepared films, by x-ray diffraction technique, disclose multi-crystalline cores covered by amorphous shells. Based on x-ray photoelectron spectroscopy and energy dispersive x-ray spectroscopy measurements, different chemistry on the NPs surfaces and volume of the NPs can be achieved by tuning the operation conditions. Furthermore, the thermal annealing process leads to the growth of the crystallite size which results in emerging some microparticles caused by accelerating Ag surface mobility. The employed technique promises a reliable route to synthesize different heterogeneous NPs with stoichiometry tunable in a wide range for multi-functional devices.

Highly porous structures consisting of niobium nanoparticles (Nb NPs) are prepared using magnetron sputtering and inert gas aggregation method. Alongside the thermally-driven evolution of nanoparticle morphology, the microstructural genesis is probed in-situ by x-ray diffraction for the temperature range up to 800 °C. The as-deposited Nb NPs are formed by the Nb core and NbOx shell. The elevated temperature triggers the gradual oxidation that proceeds until 200 °C. Above this point the structure is fully amorphous. Further increase of the temperature to 450 °C leads to a transition to the crystalline TT-Nb2O5 phase, which hexagonal structure was solved in the current study. The subsequent rise of the temperature to 600 °C results in the conversion to the orthorhombic T-Nb2O5 phase. Up to this state, the size of nanoparticles corresponds to the size of crystallites. The annealing above 600 °C causes coalescence of NPs with the formation of hundreds-of-nanometers large structures.

Nanoporous gold is of great interest for many applications due to its three dimensional interconnected porosity at nanoscale. Among all currently use techniques to obtain nanoporous gold, dealloying is one of the most used method to create a well-controlled nanoporous morphology. Only few studies report on the creation of nanoporous gold from alloy thin film deposited by magnetron co-sputtering. However, this deposition technique allows easy tune of the morphology at nanoscale. In this paper, we report on the creation of different morphologies of nanoporous gold obtained after dealloying in nitric acid of Au-Cu thin film deposited by magnetron co-sputtering. The influence of the substrate temperature during film deposition is studied by means of scanning electron microscopy and X-ray scattering analysis. We demonstrate the impact of the as-grown thin film morphology on the final nanoporous structure. We further explain the relationship between the different nanoporous morphologies and the residual stress on the as-grown thin film.

Ultra-nanocrystalline UH3-based ferromagnets with TC ≈ 200 K exhibit a flat temperature dependence of electrical resistivity with a negative slope both in the ferromagnetic and paramagnetic range. The ordered state with randomness on atomic scale, equivalent to a non-collinear ferromagnetism, can be affected by magnetic field, supressing the static magnetic disorder, which reduces the resistivity and removes the negative slope. It is deduced that the dynamic magnetic disorder in the paramagnetic state can be conceived as continuation of the static disorder in the ordered state. The experiments, performed for (UH3)0.78Mo0.12Ti0.10, demonstrate that the negative resistivity slope, observed for numerous U-based intermetallics in the paramagnetic state, can be due to the strong disorder effect on resistivity. The resulting weak localization, as a quantum interference effect which increases resistivity, is gradually suppressed by enhanced temperature, contributing by electron-phonon scattering, inelastic in nature and removing the quantum coherence.

We describe basic magnetic properties of uranium-based hydrides UTi2Hx, reported in literature as a cubic Laves phase, although the UTi2 binary phase does not exist. Using a high-temperature hydrogenation, we successfully synthesized two types of such hydrides, presumably with different H concentrations, one with a smaller lattice parameter a = 850.3 pm, which is a paramagnet close to the verge of magnetic ordering, the other with a = 858.8 pm, with a ferromagnetic ground state and ordering temperature TC = 54 K.

Colloidal solutions of metal nanoparticles (NPs) are typically produced by multi-step methods using a variety of chemicals. Resultant nanofluids require extra purification steps to remove the reactions by-products and modification steps to introduce anticoagulants for the solution stabilization. Here, we suggest a single-step method to produce nanofluid in which only two components are present: 22 nm-sized Cu NPs as a filler and polyethylene glycol (PEG, 400 g/mol) as a liquid base. The method employs magnetron sputtering to synthesize Cu NPs in a gas aggregation cluster source and their subsequent loading into vacuum-compatible PEG. The resultant nanofluid demonstrates strong plasmonic and photoluminescent activity, and shows enhanced stability over time, in contrast to conventional colloidal solutions. The approach offers an alternative for the production of nanofluids in which the processes of the NP formation are decoupled from the processes of their mixing with the liquid base.

A hardenable lightweight Mg-22 wt%Gd alloy with ultra fine grained (UFG) structure was prepared by high pressure torsion (HPT) at ambient temperature. The development of microstructure during HPT processing was investigated. A homogeneous UFG structure with grain size of 300 nm was achieved after 15 HPT revolutions. The UFG alloy exhibits enhanced strength due to work strengthening by tangled dislocations forming a dense forest throughout grains. Dislocation density in the sample was determined by positron annihilation spectroscopy (PAS) and X-ray line profile analysis (XLPA). It was found that there is an additional source of X-ray profile broadening in addition to small crystallites and micro-strains caused by dislocations. The additional micro-strain component was attributed to lattice modulation by Gd-rich nano-wires formed by agglomeration of Gd solutes and to strains arising from boundaries of crystallite domains and inter-domain interactions. Analysis of the influence of the crystallite size on the strength of UFG Mg-22 wt%Gd alloy revealed a breakdown in the Hall-Petch relationship when the crystallite size decreased below a critical value of ≈30 nm.

Low temperature magnetic ordering in the LiFePO 4 compound is investigated experimentally using M&ouml, ssbauer spectroscopy and theoretically via first principles calculations. The evaluation of experiment carried out on a powder sample is compatible with an antiferromagnetic order of Fe ion magnetic moments. When an external magnetic field is applied, Fe magnetic moments start to deviate slightly from the [010] easy magnetization direction. These findings are confirmed by means of first principles calculations, which also suggest the magnitude of single ion magnetic anisotropy and orbital and spin-dipolar contributions to the magnetic hyperfine field, which is eventually in a good agreement with the experiment. Diffraction and magnetic measurements complement the study.

Hydrogenation effects on the crystal structures and magnetic properties of Tb2Co2Ga, Tb2Ni2Ga, and Tb3Co3Ga were studied. Tb2Co2Ga, Tb2Ni2Ga (both structure type W2CoB2), and Tb3Co3Ga (structure type W3CoB3) are structurally related belonging to inhomogeneous linear structure series based on the TlI- (also referred to as CrB type) and YAlGe- (ordered derivative of the binary type UPt2) type structure motives. The hydrides Tb2Co2GaH6.2, Tb3Co3GaH9.7, and Tb2Ni2GaH5.1 were synthesized at room temperature with hydrogen pressures of 52–53 ​kPa. Hydrogenation results in strongly anisotropic lattice volume expansion ΔV/V ​= ​19.2–20.0%. It also leads to a decrease of the Curie temperature in ferromagnetic Tb2Co2Ga and Tb3Co3Ga and practically suppresses the antiferromagnetic ordering in Tb2Ni2Ga. A model of the crystal structure of the hydride Tb3Co3GaH10 with four hydrogen positions was suggested based on stronger effect of hydrogenation on the TlI-type slabs. The more complex character of the magnetic phase transitions for Tb2Co2Ga and Tb3Co3Ga presumes involvement of Co in the magnetism of these compounds, while Tb2Ni2Ga acts as a typical 4f-electron system with dominating RKKY exchange interactions.

Crystal structure, magnetic and electrical properties of thin U–Mo films and their hydrides prepared by reactive sputter deposition from metallic targets were studied. The films are metallic but with high values of electrical resistivity. Both bcc U0.79Mo0.21 thin film and the hydride (UH3)0.74Mo0.26 (β-UH3 structure type) have a very strong texture. Superconductivity is identified below Tc = 0.55 K for U0.79Mo0.21. The critical field of 1.0 T is exceeding that of α-U (0.3 T). The hydride film (UH3)0.74Mo0.26 is a ferromagnet with the Curie temperature TC = 165 K, higher concentration of Mo somewhat reduces the TC value. Deposition on a cooled substrate reduces the grain size of the hydride, approaching the limit of amorphous state. The U–Mo films and hydrides exhibit the net negative temperature coefficient of resistivity, TCR = dρ/dT, attributed to the randomness on atomic scale, yielding very strong scattering of electrons and weak localization.

Several diverse types of UH3-based hydrides can be prepared by hydrogenation of bcc U-based alloys. Pair Distribution Function (PDF) analysis using high-energy X-rays identified that the (UH3)1-x Mo x hydrides are nanocrystalline, with the structure motif based mainly on the β-UH3 structure. α-UH3 represents a minority component. On the other hand, PDF of the (UH3)1-x Zr x hydrides corresponds well to the α-UH3 crystal structure. All the hydrides are ferromagnetic, with the Curie temperature T C reaching up to 203 K.

In this study, PtxNi100-x (0 ≤ x ≤ 100) alloy catalysts were prepared using magnetron co-sputtering in order to reveal the correlation between their composition and catalytic properties as a cathode in proton exchange membrane fuel cells (PEMFCs). Fine power adjustment on magnetrons allowed to deposit alloys with precise composition and at the same time with identical thickness of 10 nm and similar morphologies. The powerful surface characterization techniques such as atomic force microscopy (AFM), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), X-ray reflectivity (XRR) and X-ray photoelectron spectroscopy (XPS) were applied to thoroughly investigate the catalytic layers. The desired composition of the films was confirmed by EDX and XRD results. All deposited layers showed similar morphologies with vertical and horizontal roughness of ~0.35 nm and ~6 nm, respectively. XRD confirmed the alloy nature of the films with one crystalline phase of the fcc PtNi. The PtxNi100-x alloys showed significant enhancement of specific power (SP) comparing to the pure Pt in PEMFC. Particularly, the Pt25Ni75 sample exhibited the highest SP of 24 kW/g(Pt). This catalyst showed a 2- and almost 10-fold improvement in SP with respect to the Pt film and commercial nanopowder Pt catalyst, respectively.

Pressure variations of the Curie temperature of the 5f ferromagnet β-UH3 were studied using the Mo-alloyed hydride (UH3)0.82Mo0.18, which is stable in air and has very similar TC and magnetization per U atom. By means of ac magnetic susceptibility a linear decrease of TC was observed for pressures up to 3.2 GPa. The coefficient dTC/dp = −2.05 K/GPa gives dlnTC/dp = 1/T*dTC/dp ≈ −0.011 GPa−1. This value is smaller than expected for a 5f-band ferromagnet with relatively short U-U distances and suggests that UH3 may be more localized than expected. Among AnX compounds, similar dependence was found e.g. for US. Revisiting existing data on lattice elasticity for β-UH3, bulk modulus B ≈ 100 GPa can be assumed, leading to dlnTC/dlnV = 1.1. Experimental data are confronted with results of GGA + U electronic structure calculations. Plausible values of direct Coulomb U and Hund’s exchange J are deduced. The lattice compression was found to reduce predominantly the orbital moments.

Uranium hydride films with the β-UH3 structure were successfully synthesized using reactive sputter deposition. Their composition can be modified, if cooling the substrate to 177 K, by incorporating Mo as alloying element, in analogy to bulk nanocrystalline (UH3)-Mo hydrides. The films were in detail studied by in situ XPS (4f, 5d, 6p, valence band), valence-band UPS, and BIS, revealing variations of electronic structure with respect to U metal, confronted with ab initio calculations. We could identify certain ionicity in the U-H bonding projected in a large shift of the 6p peaks to higher binding energies. The U-6d states partly shift above the Fermi level and partly hybridize with the H-1s states, which weakens the 5f-6d hybridization. Although large scale features of the band structure are consistently explained and 5f states remain at the Fermi level EF, spectral features close to EF are not well reproduced by DFT or DFT+U calculations. This situation suggests prominence of electron-electron correlations affecting spectral function in the conditions of intermediate 5f localization.

Metallic $5f$ materials have very strong coupling of magnetic moments and electrons mediating electrical conduction. It is caused by strong spin-orbit interaction, coming with high atomic number $Z$, together with involvement of the $5f$ states in metallic bonding. We have used the recently discovered class of uranium (ultra)nanocrystalline hydrides, which are ferromagnets with high ordering temperature, to disentangle the origin of negative temperature coefficient of electrical resistivity. In general, the phenomenon of electrical resistivity decreasing with increasing temperature in metals can have several reasons. The magnetoresistivity study of these hydrides reveals that quantum effects related to spin-disorder scattering can explain the resistivity behavior of a broad class of actinide compounds.

The possibilities of modelling the diffraction profiles from bimodal microstructure in computer program MSTRUCT are demonstrated on two examples. A special “Double Component” profile effect can be utilized for such problems. At first it was applied to an analysis of a mixture of two nanocrystalline anatase powders with different crystallite sizes and the relative ratio of both components was determined from X-ray diffraction data. In the second case study, diffraction peaks from a pure polycrystalline copper sample treated by equal channel angular pressing were fitted using a two-phase model of large recrystallized defect-free grains and ultrafine crystallites with high dislocation density. The method is shown to be suitable for determination of the relative fraction of the microstructural components as well as other parameters (e.g. dislocation density).

The isostructural decomposition of the titanium aluminium nitride supersaturated solid solution crystallising in the face centred cubic (fcc) crystal structure into the titanium-rich fcc-(Ti,Al)N and almost titanium-free fcc-(Al,Ti)N and the transformation of metastable fcc-(Ti,Al)N into the wurtzitic aluminium nitride are discussed from the crystallographic point of view by taking the observed orientation relationships between the adjacent phases into account. It is shown that the isostructural decomposition of fcc-(Ti,Al)N into Ti-rich fcc-(Ti,Al)N and fcc-(Al,Ti)N and the transformation of the metastable fcc-(Ti,Al)N into the thermodynamically stable wurtzitic phase are concurrent processes, which are controlled not only by the thermodynamic stability of the respective compound and by the diffusivity of Al and Ti, but also by the local lattice strains. A part of the local lattice strains is regarded to result from the lattice misfit at the interfaces between the titanium aluminium nitrides having different [Al]/[Ti] concentration ratios and, in the case of the fcc/wurtzite-type interface, also having different crystal structures. The phase transition of the fcc-(Ti,Al)N to the wurtzitic one was predicted to be facilitated by stacking faults. The results of crystallographic considerations were verified experimentally by using in situ high-temperature synchrotron diffraction experiments that were performed on cathodic arc evaporated (Ti,Al)N thin films containing titanium and aluminium in different amounts.

Carbon-bonded alumina manufactured by use of a novel binding system Carbores® P are among the most promising materials for future high temperature industry products. Their secure application is based on an accurate knowledge of their thermophysical properties. In this work, an experimental investigation will be presented for the determination of the coefficient of thermal expansion, thermal diffusivity, specific heat, and thermal conductivity within a temperature range up to 800 °C. Experiments are represented for materials containing various mass fractions of Carbores® P, produced through various processes. It is found that the coefficient of thermal expansion and thermal conductivity are decreased by an increasing mass fraction of Carbores® P, while the specific heat is not affected.

Simulations of scattered intensity distributions from two and three dimensional carbon structures of different shapes and sizes were done using the general Debye scattering equation. The influence of the lattice defects typical for the turbostratic structure, i.e., random fluctuations in the parallel layer spacings, random lateral translations of graphitic layers and mutual disorientations of individual parallel layers around the layers normal direction, on the resulting simulated scattered intensities were studied and discussed. The microstructure-induced changes in the line broadening, in the shape parameter in the Scherrer formula and in the lattice parameters determined from the positions of the X-ray diffraction lines are discussed in particular. The set of presented Scherrer parameters allows the calculation of the cluster sizes along and normal to the basal planes from the measured X-ray scattering. The reliability of the Warren–Bodenstein approach for scattering on turbostratic carbon structures was proven. Intensity distributions simulated using the Warren–Bodenstein approach were compared to those obtained using the general Debye scattering equation. It was confirmed that both approaches yield, for particular cluster size, similar results.

Slip casted, carbon bonded nozzles with active mullite coating arehave been simultaneously tested with uncoated nozzles in a steel casting simulator according to their clogging behavior against endogenous as well as exogenous non-metallic inclusions. After the tests with inclusions containing steel melt no clogging of particles could be observed on the active mullite coating after steel melt contact. The investigations show a position-dependent partially till completely decomposition of the mullite coating into coarse grained alumina-rich particles and a second phase with a main composition in the ternary system MnO–SiO2–Al2O3. It has been verified that these decomposition was caused by multiple reactions between the mullite coating and the substrate during heat-up as well as interactions between the coating and alloying elements of the steel melt during the tests.

The influence of the microstructure of the as-deposited cathodic arc evaporated Ti 1-x Al x N coatings and, in particular, the influence of the intrinsic lattice strains on their thermal stability were investigated by in-situ synchrotron high temperature glancing angle X-ray diffraction (HT-GAXRD) experiments up to 850 °C. The microstructure of the as-deposited coatings was adjusted by the bias voltage (U B = −40 V, U B = −80 V and U B = −120 V) and by the [Al]/([Ti] + [Al]) ratio (0.4, 0.5 and 0.6) of the used Ti–Al targets. The microstructure evolution during annealing was described in terms of the phase composition of the coatings, the aluminium content, aluminium distribution and residual lattice strains in fcc-(Ti,Al)N. Independent of the deposition parameters ([Al]/([Ti] + [Al]) ratio and bias voltage), all coatings contained a mixture of fcc-(Ti,Al)N, fcc-AlN and w-AlN after annealing at 850 °C. The [Al]/([Ti] + [Al]) ratio was found to control the amount of fcc-(Ti,Al)N, whereas the bias voltage was mainly responsible for the relative amount of fcc-AlN and w-AlN. Finally, the interplay between lattice strains and the kinetics of the spinodal decomposition of fcc-(Ti,Al)N was illustrated.

Polycrystalline samples of technical-purity Cu (99.95 wt pct) and Cu with 0.18 wt pct Zr have been processed at room temperature by equal-channel angular pressing (ECAP). The microstructure evolution and its fragmentation after ECAP were investigated by transmission electron microscopy (TEM), electron backscattered diffraction (EBSD), positron annihilation spectroscopy (PAS), and by X-ray diffraction (XRD) line-profile analysis. The first two techniques revealed an increase in the fraction of high-angle grain boundaries (HAGBs), with increasing strain reaching the value of 90 pct after eight ECAP passes. The increase was more pronounced for pure Cu samples. The following two kinds of defects were identified in ECAP specimens by PAS: (1) dislocations that represent the dominant kind of defects and (2) small vacancy clusters (so-called microvoids). A detailed XRD line-profile analysis was performed by the analysis of individual peaks and by total profile fitting. A slight increase in the dislocation density with the number of ECAP passes agreed with the PAS results. Variations in microstructural features obtained by TEM and EBSD can be related to the changes in the XRD line-broadening anisotropy and dislocation-correlation parameter.

Technical purity copper and copper with addition of 0.18 wt.% of zirconium samples processed by equal channel angular pressing with different number of passes were studied by X-ray line profile analysis. Dislocation-induced broadening is the dominant effect determining diffraction line shape. X-ray analysis reveals increasing mean dislocation density (∼1015 m – 2) with the number of ECAP passes. The character of the deformation field connected with the dislocation distribution is slightly different in pure copper than in copper with addition of zirconium and evolves significantly during 4 or 8 ECAP passes in the case of pure copper.

Equal-channel angular pressing (ECAP) belongs to advanced technologies for improving mechanical properties of materials. In the present work, the influence of the number of ECAP passes using route BC on both grain size and mechanical properties of interstitial-free steel was investigated by means of transmission electron microscopy, electron back-scattering diffraction, and microhardness testing. It was found that the grain size decreases with the increasing number of passes. At the same time, an increase in microhardness was observed. The evolution of microstructure with increasing strain imposed through ECAP, in particular the process of grain fragmentation and the formation of high-angle boundaries were also examined.

Ultrafine-grained copper and cooper–zirconium polycrystals prepared by equal-channel angular pressing following the route Bc to various strain (1, 2, 4 and 8 passes) were investigated using electron back-scatter diffraction. Equal-channel angular pressing resulted in significant grain-size reduction. The original course-grained structure evolved from prolate bands of cells/subgrains enclosed by lamellar nonequilibrium grain boundaries (after the first two passes) towards an equiaxed homogeneous microstructure with equilibrium grain boundaries (after 8 passes). Significant changes in the volume fraction and the character of grain boundaries were observed both in Cu and in Cu – Zr alloy. Pronounced evolution of twin-related boundaries (3n grain boundaries) with strain (number of ECAP passes) was found in Cu while only a weak increase of 3 and 9 grain boundaries was observed in Cu – Zr alloys.

Formation of structure defects and other microstructure phenomena in hard Cr–Al–(Si–)N, Ti–Al–(Si–)N and Zr–Al–N nanocomposite coatings with different aluminium and silicon contents deposited by using cathodic arc evaporation was investigated using a combination of X-ray diffraction and transmission electron microscopy. The subject of the microstructure studies was the analysis of the phase composition and, for the cubic phase, the determination of the stress-free lattice parameters, the crystallite size and the local disorientation of crystallites. It was found that the formation of structure defects starts with a fragmentation of the deposited clusters having the size of several tens of nanometers into nanocrystallites having the size below 12 nm. This fragmentation was driven by formation of dislocation networks. The formation of structure defects continued with the segregation of the excessive aluminium and silicon from the host structure of the transition metal nitrides that was followed by the growth of the wurtzitic AlN and an amorphous silicon nitride at higher aluminium and silicon concentrations. The microstructure of the coatings was correlated with their hardness. In all systems under study, an increase of the hardness with increasing density of the microstructure defects was observed. The maximum of the hardness was observed in the coatings containing both the cubic transition metal nitride (accommodating also aluminium and silicon) and the wurtzitic AlN.

The interplay between the deposition geometry, the chemical and phase composition, the crystallite size, the lattice strain and the direction and the degree of the preferred orientation of crystallites was investigated in the Cr1−xAlxN and Cr1−x−yAlxSiyN nanocrystalline coatings and nanocomposites, which were deposited in cathodic arc evaporation process at different positions of substrates in the deposition apparatus. The different positions of the substrates affected primarily the distance between the samples and the cathodes and consequently the chemical and phase composition of the coatings, the crystallite size, the lattice strain and the preferred orientation of crystallites. In the Cr1−xAlxN coatings, the dominating cubic crystallites were preferentially oriented with their 〈111〉 direction perpendicular to the sample surface; this out-of-plane preferred orientation of crystallites was accompanied by a strong in-plane texture. In the Cr1−x−yAlxSiyN coatings, a strong inclination of the {111} texture from the normal direction and a decay of the in-plane preferred orientation were observed in cubic crystallites with increasing silicon (and aluminium) contents.

Nano-sized clusters consisting of strongly preferentially oriented, partially coherent nanocrystallites were observed in Cr–Al–N and Cr–Al–Si–N coatings deposited using cathodic arc evaporation. Microstructure analysis of the coatings, which was done using the combination of X-ray diffraction (XRD) and transmission electron microscopy with high resolution (HRTEM), revealed furthermore stress-free lattice parameters, size and local disorientation of crystallites within the nano-sized clusters in dependence on the aluminium and silicon contents, mean size of these clusters and the kind of structure defects. Within the face-centred cubic (fcc) Cr 1 − x − y Al x Si y N phase, the stress-free lattice parameter was described by the equation a = (0.41486 − 0.00827 · x + 0.034 · y ) nm. The size of individual crystallites decreased from ∼ 11 nm in Cr 0.92 Al 0.08 N to ∼ 4 nm in Cr 0.24 Al 0.65 Si 0.10 N. These nanocrystallites formed clusters with the mean size between 36 and 56 nm. The mutual disorientation of the partially coherent nanocrystallites forming the clusters increased with increasing aluminium and silicon contents from 0.5° to several degrees. The disorientation of neighbouring nanocrystallites was explained by the presence of screw dislocations and by presence of phase interfaces in coatings containing a single fcc phase and several phases, respectively.

Phase and texture analysis using X-ray diffraction, analysis of the diffraction line broadening, analysis of the lattice parameters and high-resolution transmission electron microscopy were employed to characterize the microstructure development in the Cr–Al–Si–N thin film nanocomposites with a variable [Cr] / ([Al] + [Si]) ratio deposited by cathodic arc evaporation. At the highest chromium contents, a single face centered cubic phase formed in the coatings. Below [Cr] / ([Cr] + [Al] + [Si]) ≈ 0.52, a second crystalline phase developed that was identified as hexagonal AlN. The size of the fcc crystallites decreased with increasing aluminum and silicon contents until it reached 5 nm in the sample with the overall chemical composition Cr 0.40 Al 0.52 Si 0.08 N. The small crystallite size and the presence of two crystalline phases were found to be responsible for a high hardness of the Cr–Al–Si–N nanocomposites. Analysis of the lattice parameters revealed strong crystal anisotropy of the elastic constants in the cubic phase that decreased with increasing aluminum and silicon contents.

The microstructure of commercial rolled magnesium alloy AZ31B (nominal composition Mg–3Al–0.9Zn–0.15Mn in wt.%) was investigated with the help of light microscopy, electron backscatter diffraction (EBSD) and X-ray diffraction technique after annealing in the temperature range from room temperature (RT) to 400 °C. Tensile tests at RT were performed to show the influence of the microstructure on mechanical properties. Static recrystallization (SRX) was observed during annealing of as-received alloy at and above 150 °C. Twins play an important role during SRX and serve as nucleation sites and preferred paths for growth of grains. The strong basal texture caused by rolling was weakened by SRX. Significant differences in the stress strain curves were observed for as-received and annealed specimens.

The capability of X-ray diffraction for the microstructure investigations of metastable systems is illustrated on supersaturated and partially decomposed thin films of titanium aluminium nitrides with high aluminium content. The anisotropy of the elastic constants and their role in these investigations is discussed., Metastable phases are often used to design materials with outstanding properties, which cannot be achieved with thermodynamically stable compounds. In many cases, the metastable phases are employed as precursors for controlled formation of nanocomposites. This contribution shows how the microstructure of crystalline metastable phases and the formation of nanocomposites can be concluded from X-ray diffraction experiments by taking advantage of the high sensitivity of X-ray diffraction to macroscopic and microscopic lattice deformations and to the dependence of the lattice deformations on the crystallographic direction. The lattice deformations were determined from the positions and from the widths of the diffraction lines, the dependence of the lattice deformations on the crystallographic direction from the anisotropy of the line shift and the line broadening. As an example of the metastable system, the supersaturated solid solution of titanium nitride and aluminium nitride was investigated, which was prepared in the form of thin films by using cathodic arc evaporation of titanium and aluminium in a nitrogen atmosphere. The microstructure of the (Ti,Al)N samples under study was tailored by modifying the [Al]/[Ti] ratio in the thin films and the surface mobility of the deposited species.