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Advanced low‐density steels that meet energy shortages and high safety requirements have become a hot research topic in materials science. The addition of light elements with medium‐Al content (5 wt%) to ultrahigh‐strength pearlite cable steel alloy reduces the material density and causes a microstructural change from traditional θ‐pearlite (ferrite + cementite) to θ‐pearlite and κ‐pearlite (ferrite + cementite + κ‐carbide). The results show that the moderate addition of Al and Mn (5 wt%) promotes the formation of κ‐carbide, which inhibits the diffusion of C and significantly delays the eutectoid transformation process of pearlite. Meanwhile, the transformation free energy of pearlite increases and obviously refines the lamellar spacing of the ultrafine pearlite by κ‐carbide. Simultaneously, the interaction between κ‐carbides and dislocations is initiated, which increases the strain hardening rate of ultrafine pearlitic steel. [ABSTRACT FROM AUTHOR]

The effect of hydrogen on the fatigue behavior of materials has been studied extensively during the past 100 years, but is just poorly understood due to the complex interplay between hydrogen and deformation processes. In this context, hydrogen damage of metals is becoming one of the major challenges of decarbonization. While most work focuses on f.c.c. materials, the availability of relevant results becomes sparse when considering technologically highly relevant b.c.c. metals such as structural steels. This work uses in situ electrochemical hydrogen charging of α‐iron steels to investigate the formation and evolution of intrusions and extrusions prior to fatigue crack initiation using a new charging setup by which the specimens are charged from the interior. The advantage of this innovative technique is that the surface of the specimens can subsequently be characterized using atomic force microscopy without artefacts from electrochemical charging or corrosion. Hydrogen is shown to enhance slip localization at the early stages of damage. The developed persistent slip lines are less pronounced. By means of transmission Kikuchi diffraction, it is shown that orientation gradients between cells in the dislocation structure are much weaker in the presence of hydrogen. Hence, hydrogen appears to promote slip reversibility in b.c.c. materials. [ABSTRACT FROM AUTHOR]

Austenitic stainless steels with a bimodal harmonic structure, in which the fine grain structure (Shell) exists around the coarse grain structure (Core), are prepared by powder metallurgy to improve both strength and ductility. Herein, X‐ray diffraction contrast tomography, a 3D grain mapping technique for polycrystalline materials using ultrabright synchrotron radiation X‐rays, is used to reconstruct the grain shape and location and to evaluate the average excess dislocation density of the Core and Shell structures. This technique allows one to evaluate the excess dislocation density not only on the surface, but also inside the sample where damage occurs in tensile tests. The results show that the excess dislocation density of the Shell structure is higher than that of the Core structure. The excess dislocation density of homogeneous austenitic stainless steels with grain sizes similar to the Core structure of the harmonic structured stainless steel is higher than that at comparable stresses, indicating that the deformation of the bimodal harmonic structured alloy is localized in the fine grain structure. This is consistent with the results obtained from electron backscatter diffraction analysis, in which the surface grains are evaluated. [ABSTRACT FROM AUTHOR]

Here the possibility of utilizing X‐ray reflectivity for visualization with ≈µm spatial resolution of a surface with a heterogeneous electron density due to a partial coverage by another nanometrically thin material is demonstrated. It requires the sample to be convexly bent, thus reflecting the collimated incident beam onto a magnified image recorded by a position‐sensitive detector. By the use of a small, intense, and parallel beam such as provided by the most recent synchrotron sources, one can record such spatially resolved X‐ray reflectivity with 0.1–1 kHz frame rate. The use of the method for in situ, time‐resolved characterization of single‐layer graphene domains during their chemical vapor deposition on a naturally curved surface of a liquid copper drop is demonstrated. This method can follow the growth kinetics, including the coverage ratio, 2D crystal (flake) sizes, and distances between flakes. By taking a single scan, the individual X‐ray reflectivity curves can be reconstructed, of both covered and noncovered parts of the surface, allowing to deduce the corresponding electron density profiles perpendicular to the surface. The technique has a promising perspective for in situ study of 2D materials, ultrathin films, and self‐assemblies on liquid as well as solid surfaces. [ABSTRACT FROM AUTHOR]

Here the possibility of utilizing X‐ray reflectivity for visualization with ≈µm spatial resolution of a surface with a heterogeneous electron density due to a partial coverage by another nanometrically thin material is demonstrated. It requires the sample to be convexly bent, thus reflecting the collimated incident beam onto a magnified image recorded by a position‐sensitive detector. By the use of a small, intense, and parallel beam such as provided by the most recent synchrotron sources, one can record such spatially resolved X‐ray reflectivity with 0.1–1 kHz frame rate. The use of the method for in situ, time‐resolved characterization of single‐layer graphene domains during their chemical vapor deposition on a naturally curved surface of a liquid copper drop is demonstrated. This method can follow the growth kinetics, including the coverage ratio, 2D crystal (flake) sizes, and distances between flakes. By taking a single scan, the individual X‐ray reflectivity curves can be reconstructed, of both covered and noncovered parts of the surface, allowing to deduce the corresponding electron density profiles perpendicular to the surface. The technique has a promising perspective for in situ study of 2D materials, ultrathin films, and self‐assemblies on liquid as well as solid surfaces. [ABSTRACT FROM AUTHOR]

The statistical analysis and recovery behavior of dislocations in cold-rolled and annealed reactor pressure vessel steels with a thickness reduction of 50% were investigated by using x-ray diffraction and electron backscattered diffraction analysis in this study. A new modified Kubin & Mortensen’s method was proposed to evaluate the geometrically necessary dislocation density, and this method could effectively improve the accuracy of geometrically necessary dislocation evaluation by eliminating the effect of step size and measurement noises. Comparison analysis between modified Williamson-Hall and modified Kubin & Mortensen’s methods was also performed in this study, which shows different recovery behavior of dislocations. The electron backscattered diffraction results show that geometrically necessary dislocation density remained unchangeable after annealing treatment below and at 550°C, and it occurred to decrease above 550°C due to the occurrence of recrystallization. However, dislocations started to migrate and annihilate at 340°C according to x-ray diffraction results. A possible explanation is a difference in the effect of pairwise dislocation annihilation on statistically stored dislocations and geometrically necessary dislocations. [ABSTRACT FROM AUTHOR]

This review summarizes the current knowledge on the α″ martensite transformation in metastable β Ti alloys under different stress state conditions gained using various in situ techniques that range from the meso‐ to the nanoscale. Compared to ex situ observations, in situ observation can be conducted on a single region while changing external stimuli, and are therefore capable of elucidating the interim microstructural evolution. The strengths and shortcomings of different techniques to give insight into the martensitic transformation are identified. Both the formation of α″ martensite and its reversion on load removal are addressed. The phenomena of α″ martensite formation including preferential nucleation sites, its growth, interactions, and variant selection are described. The review also discusses the details of the macro‐ and micro‐level mechanical behavior caused by the phase transformation and highlights the research questions for further investigation. [ABSTRACT FROM AUTHOR]

Among various types of stainless steel, 304L and 316L have the most engineering applications. Herein, 304L and 316L powders with similar size distributions and morphologies are used as raw materials for selective laser melting (SLM) using the same parameters. It is found that SLM 304L has two phases, γ‐austenite (≈95%) and δ‐ferrite (≈5%) phases, while SLM 316L contains only γ‐austenite phase. The average grain size is found to be 4.9 μm (average grain size of γ‐austenite phase: 5.0 μm; δ‐ferrite: 3.4 μm) for SLM 304L and 16.7 μm for SLM 316L. The small grain size of 304L is attributed to the peritectic reaction during solidification. δ‐ferrite acts as a heterogeneous nucleation site for γ‐austenite. SLM 316L has higher hardness and yield strength than 304L. Results obtained from the comparative study indicate that adding ferrite stabilizer elements (e.g., Cr, Mo, Si, Nb, or Ti) into 316L can lead to peritectic reaction or austenite to ferrite solid phase transformation, which is a possible approach for grain refinement. [ABSTRACT FROM AUTHOR]

This paper studies the influence of the regression re‐aging (RRA) process on the mechanical properties and corrosion resistance of 7075. In the RRA heat treatment, the material properties are markedly affected by the variation of parameters in the regression stage. When the regression temperature and the regression duration increase, the mechanical properties of the material decrease. There was no intergranular corrosion in the samples treated by RRA, while obvious intergranular corrosion occurred in the T6 sample. Compared with the T6 sample, the RRA‐190‐0.5 sample with optimized parameters has a higher density of the precipitated phase and narrower precipitate‐free zone, and the precipitated phase along the grain boundary is discontinuous, isolated, and short. Compared with the single‐stage peak aging treatment, the RRA treatment can considerably improve the corrosion resistance and stress corrosion resistance but slightly reduce the strength. The best heat treatment process condition is 120°C/24 h + 190°C/0.5 h + 120°C/24 h. [ABSTRACT FROM AUTHOR]

The usability of the magnetic Barkhausen noise (MBN) technique for monitoring the critical state of plastic straining in the case of interstitial free (IF) steel is demonstrated. IF steels are frequently employed in the automotive industry (e.g., automotive body parts—doors, trunks, wheel arches, etc.), and rupture of components made of these steels occurs during cold forming. Alteration of microstructure expressed in many terms and the corresponding MBN features after the variable degree of plastic strains developed by the uniaxial tensile loading are investigated. It is reported that the effective value of MBN, as well as the shift of MBN envelopes toward higher magnetic fields, can be proposed as the suitable MBN features alerting the incoming matrix breakage. Moreover, the higher MBN in the direction of exerted load at the expense of the perpendicular direction can be found as a result of domain walls realignment. [ABSTRACT FROM AUTHOR]

The reliability of semiconductor materials with electrical and optical properties are connected to their structures. The elastic strain field and tilt analysis of the crystal lattice, detectable by the variation in position and shape of the diffraction peaks, is used to quantify defects and investigate their mobility. The exploitation of high‐resolution X‐ray diffraction‐based methods for the evaluation of structural defects in semiconductor materials and devices is reviewed. An efficient and non‐destructive characterization is possible for structural parameters such as, lattice strain and tilt, layer composition and thickness, lattice mismatch, and dislocation density. The description of specific experimental diffraction geometries and scanning methods is provided. Today's X‐ray diffraction based methods are evaluated and compared, also with respect to their applicability limits. The goal is to understand the close relationship between lattice strain and structural defects. For different material systems, the appropriate analytical methods are highlighted. [ABSTRACT FROM AUTHOR]

This study aims to investigate additively manufactured Ti6242S specimens compared with the widely used Ti64 alloy with a special focus on microstructure and mechanical properties as well as the impact of subsequent heat treatments. As the Ti6242S alloy, which belongs to the family of near‐α Ti‐alloys, is often used at higher service temperatures, uniaxial tensile tests are performed at a room temperature up to 500 °C. By means of optical and electron microscopy, it is found that the as‐built microstructure consists of acicular α′ martensite, which decomposes to α + β during the subsequent heat treatment. A special focus on the prior microstructure shows that the Ti6242S alloy has a small β grain size, which influences the resulting α′ microstructure after the β → α′ phase transformation. Furthermore, the mechanical properties at room temperature as well as elevated temperatures exceed the values for selective laser melted Ti64 and conventionally cast Ti6242 material. The heat‐treated Ti6242S specimens exhibit an ultimate tensile strength of about 1213 MPa including a ductility of 11.3% at room temperature. These values may path the way to a substitution of the widely used Ti64 alloy by the near‐α Ti6242S alloy, especially for highly loaded components at elevated temperatures. [ABSTRACT FROM AUTHOR]

The texture deterioration and work hardening in nonoriented electrical steel during the necessary shearing and blanking process are relaxed and avoided by the slanted blades, which possess certain angles with sheets at the transverse direction of blades. The conditions of collapse edges and excrescent burrs are ameliorated conveniently with the new technical idea. At the stress coverage by the shearing process, the deformed grains rotate from the original γ (<111>//ND) fiber texture toward the near‐{001} texture, which benefits the dominant advantage of the favorable textures and the improvements in magnetic performances. According to the investigation, adopting the single‐slanted blade with 45° with a flat backplate for blanking sheets into sections or complex shapes shows low hardened coverage, small sheared zones without extensive fault zones on the sheared planes, and significant texture optimization in deformed grains. This investigation benefits the shearing and blanking methods for optimizing cutter layouts. [ABSTRACT FROM AUTHOR]

Strain hardening is a useful mechanism for improving mechanical properties in materials. This study investigates the strain‐hardening behavior of an AA6060 alloy processed by equal channel angular pressing (ECAP) up to 12 passes. Analysis by electron backscattered diffraction (EBSD) shows that the average geometrically necessary dislocations (GNDs) density increases continually up to the fourth pass and then saturates at a value of ≈1.85 × 1014 m−2. Hollomon and Kocks–Mecking–Estrin (KME) analysis are used to investigate the strain‐hardening behavior of the resulting ultrafine‐grained alloy. Results indicate that the strain‐hardening capacity (HC) and the strain‐hardening exponent (n) of all deformed specimens are lower in comparison with the as‐received condition. Moreover, the strain‐hardening rate fluctuates with the ECAP passes. First, it increases from the first ECAP pass up to the fourth pass, then diminishes up to the fifth pass, and finally, it increases again with further deformation. The difference in the strain‐hardening behavior of the ECAPed AA6060 is examined in terms of the grain size effect. It is shown that the strain‐hardening curves change notably with diminishing the grain size. In addition, the KME model is used to depict the storage and annihilation of dislocations in the ECAPed specimens. [ABSTRACT FROM AUTHOR]

Material issues pose a significant challenge for the design of future fusion reactors. From a historic point of view, the material mix used for the first wall of a fusion reactor has continually evolved, from original steel vessels to carbon and other low‐Z materials such as beryllium to tungsten as the primary candidate for a reactor's first wall armor and divertor material. For materials considered for fusion applications, a highly integrated approach is necessary. Resilience against neutron damage, good power exhaust, and oxidation resistance during accidental air ingress are design relevant issues while deciding on new materials or improving upon baseline materials. Neutron‐induced effects, e.g., transmutation adding to embrittlement, retention, and changes to thermomechanical properties, are crucial to material performance. In this contribution, the recent progress (2013–2019) in fusion materials development for current and future fusion devices, at Forschungszentrum Jülich GmbH, with activities focussing on advanced materials and their characterization is given. It is a continuation and extension of the work given by Coenen et al. [ABSTRACT FROM AUTHOR]

For future fusion reactors, tungsten (W) is currently the main candidate for the application as plasma‐facing material due to its several advanced properties. To overcome the brittleness of W, randomly distributed short W fiber‐reinforced W (Wf/W) composites have been developed using field‐assisted sintering technology (FAST). Herein, Wf/W materials with different fiber volume fraction (20–60%) are manufactured by FAST process to study the fiber volume fraction influence on the composite properties. Wf/W with ductile fibers and brittle fibers is produced using different tool setups during the production. Three‐point bending tests on prenotched samples, 4‐point bending tests, and tensile tests have been performed to determine the fracture behavior and flexural/tensile strength of the material. Wf/W materials with 30–40% fiber volume fraction exhibit a promising pseudoductile behavior, similar to fiber‐reinforced ceramic composites. However, Wf/W with 20% and >50% fiber volume fraction shows only a limited extrinsic toughening effect. In terms of flexural strength, with increasing fiber volume fraction, the tensile/flexural strength does not show a clear increasing tendency, or even lightly decreases. [ABSTRACT FROM AUTHOR]

Herein, two kinds of Fe–9Cr–8Al oxide dispersion‐strengthened (ODS) steels (prealloyed and postalloyed) are fabricated via mechanical alloying (MA), hot isostatic pressing (HIP), and subsequent hot forging. Microstructures of the milled powder and forged bulk materials are carefully characterized. The results show that the adding sequence of Al has a significant impact on the microstructure. For the postalloyed sample (adding Al during ball milling), a dual‐phase structure composed of reticular Al‐rich regions and a steel matrix is formed in the milled powder due to the highly mismatched deformability between the Al powder and the Fe–9Cr powder during ball milling. For the prealloyed sample (adding Al prior to ball milling), Al is solid solutionized into the steel matrix before ball milling, and there is no dual‐phase structure in the milled powder. In the final bulk materials, the average grain size of the prealloyed sample is much larger than that of the postalloyed sample. Moreover, the matrix of the postalloyed sample has a bimodal grain structure consisting of coarse grains closely surrounded by fine grains, whereas the prealloyed sample has a relatively uniform distribution of coarse grains. The coarsening mechanisms of Al addition on the microstructure are also discussed. [ABSTRACT FROM AUTHOR]

Low‐carbon steel sheets are severely plastic deformed to strains of up to ≈3.48 and subsequently heat treated by conventional annealing followed by water‐quenching. Four temperatures are chosen for the annealing below and over the Ac1 and Ac3 transformation lines. The effects of post‐deformation heat treatment are investigated by evaluating the microstructure and mechanical properties, including strength, ductility, work hardening capability, and hardness. A maximum increase of 86% in the strength is obtained through intercritical annealing and quenching of the samples subjected to strain of 1.16. It is interesting that both the elongation and ultimate tensile strength values are higher after heat treatment at a variety of temperatures in comparison with those of the non‐treated samples; up to 197% for the former and up to 33% for the latter. These would be achieved in combination with yield ratios even lower than that of the as‐received material, demonstrating the higher deformation capability of the specimens. However, these beneficial outcomes are deteriorated toward higher amounts of strain. Despite the heat treated undeformed low‐carbon steels, the stress − strain curves for heat treated deformed samples show little or no discontinuous yielding correlated to variations of mobile dislocations density as a result of microstructural evolution. [ABSTRACT FROM AUTHOR]

The plastic deformation of polycrystalline metals is primarily carried by the crystallographic glide of dislocations and growth of deformation twins. According to the thermodynamic theory of slip, dislocation motion is thermally activated, while deformation twinning is an athermal process. Dislocations must overcome barriers in order to move, while twins must relax the stored energy while growing. These concepts define the critical activation stresses on a slip or twin crystallographic system and how they evolve with plastic strain. This article reviews recent advances in the development of a model for the critical activation stresses for thermally activated glide and the expansion of deformation twins, its implementation into polycrystal plasticity models, and several applications for predicting the constitutive response of polycrystalline metals. Calculations are performed for a range of polycrystalline metals differing in microstructural complexity and crystal structure. These examples include face‐centered cubic AA6022‐T4, IN718, Haynes 25, and pure Cu, body‐centered cubic Nb, Ta, Ta‐10W, and steel DP590, hexagonal close‐packed pure Be, pure Zr, pure Ti, AZ31, Mg4Li, and orthorhombic U. Excellent agreement with experimental measurement are demonstrated in terms of texture, stress–strain response, and geometrical changes in the samples during deformation for all these metals. [ABSTRACT FROM AUTHOR]

X‐ray refractive lenses are widely used optical devices at today synchrotron X‐ray sources. In the present paper we demonstrate negative influence of the X‐ray diffraction on optical properties of monocrystalline X‐ray refractive lenses in operation. Several types of single‐crystal diamond lenses were studied in X‐ray spectroscopy mode at the European Synchrotron Radiation Facility. X‐rays were propagating through individual lenses, stacked together in a row, and the transmitted intensity was measured at different energies. While using the stack of crystallographically co‐aligned lenses, we obtained the strong maximal reduction of 35% in an intensity of the outgoing signal. The effect was caused by diffraction losses in the single‐crystal diamond and also called “X‐ray glitch.” The magnitude of the effect was then minimized down to ∼10% by use of stacks with different crystallographic orientation of individual lenses inside. At the same time, X‐ray glitches did not affect any focal spot's size or shape while only arousing the darkening of the focal spot at exact energies of X‐ray glitches. [ABSTRACT FROM AUTHOR]

In this study we present microstructural data from hydrothermal veins in the sedimentary cover and the igneous basement recovered from Hole U1414A, Integrated Ocean Drilling Program (IODP) Expedition 344 (Costa Rica Seismogenesis Project), to constrain deformation mechanism operating in the subducting Cocos Plate. Cathodoluminescence studies, mechanical e-twin piezometry and electron backscatter diffraction (EBSD) analyses of carbonate veins were used to give insights into the deformation conditions and to help to understand the tectonic deformation history of the Cocos Plate offshore Costa Rica. Analyses of microstructures in the sedimentary rocks and in the basalt of the igneous basement reveal brittle deformation, as well as crystal-plastic deformation of the host rock and the vein material. Cathodoluminescence images showed that in the basalt fluid flow and related precipitation occurred over several episodes. The differential stresses, obtained from two different piezometers using the same parameter (twin density), indicate various mean differential stresses of 49 ± 11 and 69 ± 30 MPa and EBSD mapping of calcite veins reveals low-angle subgrain boundaries. Deformation temperatures are restricted to the range from 170°C to 220°C, due to the characteristics of the existing twins and the lack of high-temperature intracrystalline deformation mechanisms (>220°C). The obtained results suggest that deformation occurred over a period associated with changes of ambient temperatures, occurrence of fluids and hydrofracturing, induced differential stresses due to the bending of the plate at the trench, and related seismic activity. [ABSTRACT FROM AUTHOR]

The work describes the effect of heat treatment on microstructure, and mechanical behavior titanium and niobium modified 9% chromium steel. The initial cast and forged microstructures consist of martensitic structure. The martensitic structure changes with increasing tempering temperature. Fine precipitates are found during tempering at 700 °C. Precipitates are carbides of chromium, niobium, and titanium. The room temperature tensile behavior of the steel is strongly dependent on processing and subsequent heat treatment. The tensile properties (YS and UTS) increase with increasing tempering temperature from 700 to 750 °C. The tensile properties of the steel improve in case of rolling sample compared to forging sample due to texture formation. But tensile properties decrease with increasing tempering time from 1 to 5 h at a fixed temperature (700 °C). The high-temperature tensile test result shows that YS and UTS decrease whereas ductility increases with increasing temperature. True stress also decreases with increasing temperature. [ABSTRACT FROM AUTHOR]

This is a brief comment to highlight and discuss issues with regards to the high resolution, cross correlation-based, electron backscatter diffraction (HR-EBSD) results presented within the work of He et al. (2016) Advanced Engineering Materials. In this comment, two specific concerns are raised: one, the stress measurements, reported to be as high as 20 GPa, are unreasonable and due to a known artefact in the form of HR-EBSD analysis, which has been corrected in state-of-the-art measurements by patterning remapping; and two, the GND field measurements are incorrectly calculated and show the variations in lattice rotation and are no derived from the gradient of the lattice rotation field, as required when following Nye's analysis. An example of reasonable data is presented to highlight how these artefacts can be avoided in practice using more appropriate analysis techniques. [ABSTRACT FROM AUTHOR]

This study aims to characterize the spatial distributions of grain-scale stress/strain and geometrical necessary dislocations (GNDs) in TA15 titanium alloy subjected to tensile deformation at room temperature. The microstructures under different strains are investigated through electron backscatter diffraction (EBSD) measurements. Evolution of intergranular stress/strain is revealed by analysis of high angular resolution EBSD patterns. The spatial distributions of GNDs are calculated using a self-developed routine. Results indicate that many factors influence the spatial distributions of grain-scale residual stress/strain and GNDs during plastic deformation, and the dominant factor varies with the changes in microstructure characteristics and macroscopic deformation parameters. [ABSTRACT FROM AUTHOR]

Copyright of Materialwissenschaft und Werkstoffechnik is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Materialwissenschaft und Werkstoffechnik is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In the present study the relative angular resolution of an electron backscatter diffraction system based on Hough transform analysis has been determined with a silicon single crystal wafer. The resolution is found to be better than 0.1° and can be easily improved by repetition of measurements. A test measurement on a BaFe2As2 thin film, where disorientations of 0.1° and less are present, was performed using the cross correlation electron backscatter diffraction technique. The same measurement is evaluated with the Hough transform technique. Comparing both techniques give evidence of a relative resolution of better than 0.1°. However, in specimen areas with strain inhomogeneities a deviation along one rotation axis can be observed. [ABSTRACT FROM AUTHOR]

The article focuses on a study done in order to determine microstructure changes in transformation induced plasticity (TRIP) steel, reinforced by zirconia partly stabilized by the addition of magnesium (Mg-PSZ) composites. It informs that low compressive deformation phase transformation in Mg-PSZ utilizes the polymorphism of the partially stabilized zirconia ceramic.

Copyright of Materialwissenschaft und Werkstoffechnik is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In situ neutron-diffraction experiments at the spallation neutron source, simultaneously illuminating the diffraction of the matrix and the strengthening nano precipitates, allow the determination of their plastic deformation. An irreversible neutron-diffraction-profile evolution of the nano precipitates is observed. However, there is no conclusive trend of the nano-precipitate peak-width evolution subjected to the greater stress levels. Hence, in the present work, molecular-dynamics simulations are applied to reveal the deformation mechanisms of the nano precipitate and its interaction with the surrounding matrix. The microstructure size, dislocation content, and structural parameters of the nano precipitates, quantified by X-ray, transmission electron microscopy, and small-angle neutron scattering, are used as the simulation input and reference. The simulation results show that there are two competing deformation mechanisms, which lead to the fluctuation of the nano-precipitate-diffraction widths, occurring during the higher plastic deformation stages. [ABSTRACT FROM AUTHOR]