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The embrittlement of metallic alloys by liquid metals leads to catastrophic material failure and severely impacts their structural integrity. The weakening of grain boundaries (GBs) by the ingress of liquid metal and preceding segregation in the solid are thought to promote early fracture. However, the potential of balancing between the segregation of cohesion-enhancing interstitial solutes and embrittling elements inducing GB de-cohesion is not understood. Here, the mechanisms of how boron segregation mitigates the detrimental effects of the prime embrittler, zinc, in a Σ5 [001] tilt GB in α-Fe (4 at.% Al) is unveiled. Zinc forms nanoscale segregation patterns inducing structurally and compositionally complex GB states. Ab initio simulations reveal that boron hinders zinc segregation and compensates for the zinc-induced loss in GB cohesion. The work sheds new light on how interstitial solutes intimately modify GBs, thereby opening pathways to use them as dopants for preventing disastrous material failure., (© 2023 The Authors. Advanced Materials published by Wiley-VCH GmbH.)

Quantitative and qualitative residual stress evolution in low-alloyed steel during heat treatment is investigated on three different length scales for sourgas resistant seamless steel tubes: on the component level, on the level of interdendritic segregation and on precipitate scale. The macroscopic temperature, phase and stress evolution on the component scale result from a continuum model of the heat treatment process. The strain and temperature evolution is transferred to a mesoscopic submodel, which resolves the locally varying chemistry being a result of interdendritic segregation. Within the segregation area and the surrounding matrix precipitates form. They are categorized with respect to their tendency for formation of microscopic residual stresses. After rapid cooling macroscopic stresses up to 700 MPa may form dependent on the cooling procedure. Mesoscopic stresses up to Δ50 MPa form depending on the extent of segregation. Carbides and inclusions occuring in low-alloyed steel are ranked by their tendency for residual stress formation in the iron matrix. This scale bridging study gives an overview of residual stresses, their magnitude and evolution on three different length scales in low-alloyed steels and the results presented can serve as a input for steel design.

In the automotive industry, corrosion protected galvanized advanced high strength steels with high ductility (AHSS-HD) gain importance due to their good formability and their lightweight potential. Unfortunately, under specific thermomechanical loading conditions such as during resistance spot welding galvanized, AHSS-HD sheets tend to show liquid metal embrittlement (LME). LME is an intergranular decohesion phenomenon leading to a drastic loss of ductility of up to 95%. The occurrence of LME for a given galvanized material mainly depends on thermal and mechanical loading. These influences are investigated for a dual phase steel with an ultimate tensile strength of 1200 MPa, a fracture strain of 14% and high ductility (DP1200HD) by means of systematic isothermal hot tensile testing on a Gleeble ® 3800 thermomechanical simulator. Based on the experimental findings, a machine learning procedure using symbolic regression is applied to calibrate an LME damage model that accounts for the governing quantities of temperature, plastic strain and strain rate. The finite element (FE) implementation of the damage model is validated based on the local damage distribution in the hot tensile tested samples and in an exemplary 2-sheet resistance spot weld. The developed LME damage model predicts the local position and the local intensity of liquid metal induced cracking in both cases very well.

Resistance spot welding (RSW) is a common joining technique in the production of car bodies in white for example, because of its high degree of automation, its short process time, and its reliability. While different steel grades and even dissimilar metals can be joined with this method, the current paper focuses on similar joints of galvanized advanced high strength steel (AHSS), namely dual phase steel with a yield strength of 1200 MPa and high ductility (DP1200HD). This material offers potential for light-weight design. The current work presents a multi-physical finite element (FE) model of the RSW process which gives insights into the local loading and material state, and which forms the basis for future investigations of the local risk of liquid metal assisted cracking and the effect of different process parameters on this risk. The model covers the evolution of the electrical, thermal, mechanical, and metallurgical fields during the complete spot welding process. Phase transformations like base material to austenite and further to steel melt during heating and all relevant transformations while cooling are considered. The model was fully parametrized based on lab scale material testing, accompanying model-based parameter determination, and literature data, and was validated against a large variety of optically inspected burst opened spot welds and micrographs of the welds.

This work provides an analysis of X-ray micro computed tomography data of Sn-xBi solders with x = 20, 30, 35, 47, 58 wt.% Bi. The eutectic thickness, fraction of eutectic and primary phase are analyzed. Furthermore, the 3D data is evaluated by means of morphology parameters, such as, shape complexity, flatness, elongation and mean intercept length tensor. The investigated alloys are categorized in three groups based on their morphology, which are described as "complex dominant", "complex- equiaxed" and "mixed". The mechanical behavior of Sn-Bi alloys in the semi-solid configuration and the correlation with microstructural parameters are discussed. A varying degree of geometric anisotropy of the investigated alloys is found through the mean intercept length tensor. Representative volume element models for finite element simulations (RVE-FEM) are created from tomography data of each alloy to analyze a correlation of geometric and elastic anisotropy. The simulations reveal an elastic isotropic behavior due to the small difference of elastic constants of primary and eutectic phase. A discussion of properties in the semi-solid state and liquid phase healing is provided.

Hydrogen embrittlement (HE) is one of the main limitations in the use of advanced high-strength steels in the automotive industry. To have a better understanding of the interaction between hydrogen (H) and a complex phase steel, an in-situ method with plasma charging was applied in order to provide continuous H supply during mechanical testing in order to avoid H outgassing. For such fast-H diffusion materials, only direct observation during in-situ charging allows for addressing H effects on materials. Different plasma charging conditions were analysed, yet there was not a pronounced effect on the mechanical properties. The H concentration was calculated while using a simple analytical model as well as a simulation approach, resulting in consistent low H values, below the critical concentration to produce embrittlement. However, the dimple size decreased in the presence of H and, with increasing charging time, the crack propagation rate increased. The rate dependence of flow properties of the material was also investigated, proving that the material has no strain rate sensitivity, which confirmed that the crack propagation rate increased due to H effects. Even though the H concentration was low in the experiments that are presented here, different technological alternatives can be implemented in order to increase the maximum solute concentration.

A model-based process control of material production processes demands realistic material models describing the local evolution of the thermal and mechanical state variables, i.e., temperature, stress, strain, or plastic strain, for the relevant microstructure state. In the present work, a material model for the specific microstructure in a continuously cast strand shell, viable for reproducing cyclic viscoplastic effects, was developed for a 0.17 wt.% C steel. Experimental data was generated using directly-cast samples and a well-controllable testing facility to apply representative loading conditions. Displacement- and force-controlled experiments in the temperature range of 700-1100 °C were conducted, with a special focus on the relevant strain rates documented for the straightening operation. A temperature-dependent constitutive material model combining elastic, plastic, and viscoplastic effects was parameterized to fit the whole set of experimentally-determined material response curves. In order to account for the cyclic plastic material response, a combination of isotropic and kinematic hardening was considered. The material model sets a new standard for the material description of a continuously cast strand shell, and it can be applied in elaborate continuous casting simulations.

Fundamental understanding of H localization in steel is an important step towards theoretical descriptions of hydrogen embrittlement mechanisms at the atomic level. In this paper, we investigate the interaction between atomic H and defects in ferromagnetic body-centered cubic (bcc) iron using density functional theory (DFT) calculations. Hydrogen trapping profiles in the bulk lattice, at vacancies, dislocations and grain boundaries (GBs) are calculated and used to evaluate the concentrations of H at these defects as a function of temperature. The results on H-trapping at GBs enable further investigating H-enhanced decohesion at GBs in Fe. A hierarchy map of trapping energies associated with the most common crystal lattice defects is presented and the most attractive H-trapping sites are identified.

An in situ hydrogen (H) plasma charging and in situ observation method was developed to continuously charge materials, while tensile testing them inside a scanning electron microscope (SEM). The present work will introduce and validate the setup and showcase an application allowing high-resolution observation of H-material interactions in a Ni-based alloy, Alloy 718. The effect of charging time and pre-straining was investigated. Fracture surface observation showed the expected ductile microvoid coalescence behavior in the uncharged samples, while the charged ones displayed brittle intergranular and quasi-cleavage failure. With the in situ images, it was possible to monitor the sample deformation and correlate the different crack propagation rates with the load-elongation curves. H-charging reduced the material ductility, while increasing pre-strain decreased hydrogen embrittlement susceptibility due to the possible suppression of mechanical twinning during the tensile test and, therefore, a reduction in H concentration at grain and twin boundaries. All the presented results demonstrated the validity of the method and the possibility of in situ continuously charging of materials with H without presenting any technical risk for the SEM.

Residual stresses in quenched seamless steel tubes highly depend on the cooling conditions to which the tubes have been subjected. The design aspect of how to use controlled cooling strategies in multiphase steel tubes to achieve certain residual stress and phase configurations is discussed. In an experimentally validated finite element (FE) model considering a coupled evolution of martensite and bainite, three cooling strategies are tested for a low-alloyed 0.25 wt.% C steel tube. The strategies are (i) external cooling only, (ii) internal and external cooling for low residual stresses in a mainly martensitic tube, and (iii) internal and external cooling with low cooling rate for a mainly bainitic tube. The strategies represent design cases, where low residual stresses with different phase compositions are provoked, in order to show the potential of numerical analysis for residual stress and property design. It can be concluded that, for the investigated steel class, intense external cooling leads to a characteristic residual stress profile regardless of the dimension. A combination of external and internal cooling allows a more flexible design of residual stress and phase distribution by choosing different cooling parameters (i.e., water amount and cooling times). In general, lower cooling rates lead to lower thermal misfit strains, and thus less plasticity and lower residual stresses., Competing Interests: The authors declare no conflict of interest.

In this work, we present and test an approach based on an inverse model applicable to the control of induction heat treatments. The inverse model is comprised of a simplified analytical forward model trained with experiments to predict and control the temperature of a location in a cylindrical sample starting from any initial temperature. We solve the coupled nonlinear electromagnetic-thermal problem, which contains a temperature dependent parameter α to correct the electromagnetic field on the surface of a cylinder, and as a result effectively the modeled temperature elsewhere in the sample. A calibrated model to the measurement data applied with the process information such as the operating power level, current, frequency, and temperature provides the basic ingredients to construct an inverse model toolbox, which finally enables us to conduct experiments with more specific goals. The input set values of the power supply, i.e., the power levels in the test rig control system, are determined within an iterative framework to reach specific target temperatures in prescribed times. We verify the concept on an induction heating test rig and provide two examples to illustrate the approach. The advantages of the method lie in its simplicity, computationally cost effectiveness and independence of a prior knowledge of the internal structure of power supplies., Competing Interests: The authors declare no conflict of interest.

Load-displacement curves measured during indentation experiments on thin films depend on non-homogeneous intrinsic film microstructure and residual stress gradients as well as on their changes during indenter penetration into the material. To date, microstructural changes and local stress concentrations resulting in plastic deformation and fracture were quantified exclusively using numerical models which suffer from poor knowledge of size dependent material properties and the unknown intrinsic gradients. Here, we report the first in-situ characterization of microstructural changes and multi-axial stress distributions in a wedge-indented 9 μm thick nanocrystalline TiN film volume performed using synchrotron cross-sectional X-ray nanodiffraction. During the indentation, needle-like TiN crystallites are tilted up to 15 degrees away from the indenter axis in the imprint area and strongly anisotropic diffraction peak broadening indicates strain variation within the X-ray nanoprobe caused by gradients of giant compressive stresses. The morphology of the multiaxial stress distributions with local concentrations up to -16.5 GPa correlate well with the observed fracture modes. The crack growth is influenced decisively by the film microstructure, especially by the micro- and nano-scopic interfaces. This novel experimental approach offers the capability to interpret indentation response and indenter imprint morphology of small graded nanostructured features.

Unlabelled: This paper examines the contribution of incompleteness/'not just right experiences' (NJREs) to an understanding of the relationship between obsessive-compulsive disorder (OCD) and obsessive-compulsive personality traits (OCPTs). It investigates the association of specific OCD symptom dimensions with OCPTs, conceptualized as continuous phenomena that are also observable below the diagnostic threshold. As empirical findings and clinical observation suggest that incompleteness feelings/NJREs may play a significant affective and motivational role for certain OCD subtypes, but also for patients with accentuated OCPTs, we hypothesized that OCPTs are selectively linked with incompleteness-associated OCD symptom dimensions (ordering, checking, hoarding and counting). Moreover, we assumed that this selective relationship cannot be demonstrated any more after statistical control of incompleteness, whereas it is preserved after statistical control of anxiety, depression, pathological worry and harm avoidance. Results from a study with a large clinical sample (n = 185) partially support these hypotheses and suggest that NJREs may be an important connecting link between specific OCD symptom dimensions, in particular ordering and checking, and accentuated OCPTs., Key Practitioner Message: Obsessive-compulsive personality traits (OCPTs) are positively related to obsessive-compulsive disorder symptom dimensions (ordering, checking, hoarding and counting) hypothesized or found to be associated with incompleteness/'not just right experiences' (NJREs), but not to washing and obsessions. This positive relationship, which is strongest for ordering and checking, is eliminated when NJREs are statistically controlled. Ordering, checking and accentuated OCPTs may share NJREs as a common affective-motivational underpinning.Dysfunctional behaviour patterns of people with accentuated OCPTs or obsessive-compulsive personality disorder (OCPD) may be viewed as efforts to avoid or reduce subjectively intolerable NJREs. On the basis of such a conceptualization of OCPD as an emotional disorder, a novel treatment approach for OCPD focusing on habituation to NJREs could be developed., (Copyright © 2013 John Wiley & Sons, Ltd.)

Novel scanning synchrotron cross-sectional nanobeam and conventional laboratory as well as synchrotron Laplace X-ray diffraction methods are used to characterize residual stresses in exemplary 11.5 µm-thick TiN coatings. Both real and Laplace space approaches reveal a homogeneous tensile stress state and a very pronounced compressive stress gradient in as-deposited and blasted coatings, respectively. The unique capabilities of the cross-sectional approach operating with a beam size of 100 nm in diameter allow the analysis of stress variation with sub-micrometre resolution at arbitrary depths and the correlation of the stress evolution with the local coating microstructure. Finally, advantages and disadvantages of both approaches are extensively discussed.

The influence of a local thermal treatment on the properties of Ti-Al-N coatings is not understood. In the present work, a Ti 0.52 Al 0.48 N coating on a WC-Co substrate was heated with a diode laser up to 900 °C for 30 s and radially symmetric lateral gradients of phases, residual stress and hardness were characterized ex - situ using position-resolved synchrotron X-ray diffraction, Raman spectroscopy, transmission electron microscopy and nanoindentation. The results reveal (i) a residual stress relaxation at the edge of the irradiated area and (ii) a compressive stress increase of few GPa in the irradiated area center due to the Ti-Al-N decomposition, in particular due to the formation of small wurtzite (w) AlN domains. The coating hardness increased from 35 to 47 GPa towards the center of the heated spot. In the underlying heated substrate, a residual stress change from about - 200 to 500 MPa down to a depth of 6 μm is observed. Complementary, in - situ high-temperature X-ray diffraction analysis of stresses in a homogeneously heated Ti 0.52 Al 0.48 N coating on a WC-Co substrate was performed in the range of 25-1003 °C. The in - situ experiment revealed the origin of the observed thermally-activated residual stress oscillation across the laser heated spot. Finally, it is demonstrated that the coupling of laser heating to produce lateral thermal gradients and position-resolved experimental techniques opens the possibility to perform fast screening of structure-property relationships in complex materials.

Introduction: The 20-item Obsessive-Compulsive Trait Core Dimensions Questionnaire (OCTCDQ) assesses two motivational dimensions of OCD, harm avoidance and incompleteness., Method: Psychometric properties and construct validity of a German version were examined in 202 patients with OCD. A shortened and statistically optimized version was developed on the basis of a structural equation modelling approach., Results: As a confirmatory factor analysis showed a poor model fit for the German translation, the model was revised. The resulting 10-item version (OCTCDQ-R) showed a good fit. Internal consistency is excellent for incompleteness and satisfactory for harm avoidance. Relationships with OCD symptom severity, anxiety, worry and obsessive-compulsive personality traits support the construct validity., Conclusion: The OCTCDQ-R is a reliable and valid measure to assess the individual significance of incompleteness and harm avoidance in OCD patients., (© Georg Thieme Verlag KG Stuttgart · New York.)

This article reports on the integration and revision of two self-report measures of obsessive-compulsive symptoms based on data from an obsessive-compulsive disorder (OCD) sample (n=228): the Vancouver Obsessional-Compulsive Inventory (VOCI) and the Symmetry Ordering and Arranging Questionnaire (SOAQ). The revised measure provides scores on five symptom subscales (Contamination, Checking, Hoarding, Symmetry and Ordering, Obsessions). It shows improvement upon current versions in several ways: it has a good model fit, eliminates redundancy, reduces overlap across subscales, is much shorter, and covers those OCD dimensions most frequently identified in factor-analytic studies. Strengths of the revision compared with other measures are high distinctiveness of subscales, discriminant validity with depression and anxiety, and a more fine-grained and comprehensive assessment of obsessional contents.

The purpose of the present study was to examine the psychometric properties, factorial structure, and validity of the Padua Inventory-Washington State University Revision and of the Padua Inventory-Revised in a large sample of patients with obsessive-compulsive disorder (n = 228) and with anxiety disorders and/or depression (n = 213). The five-factor structures of both revisions were not replicated. A 24-item revision, referred to as the Padua Inventory-Palatine Revision (PI-PR), was developed on the basis of both theoretical and statistical considerations. The PI-PR assesses six subscales: Contamination and Washing, Checking, Numbers, Dressing and Grooming, Rumination, and Harming Obsessions and Impulses. The results demonstrate that the PI-PR is a brief, psychometrically sound, and valid measure for the assessment of a broad range of obsessive-compulsive symptoms, which has important advantages over both previous revisions.

Incompleteness (INC) and harm avoidance (HA) are motivational core dimensions of OCD. While HA-related concepts (e.g., inflated responsibility, overestimation of threat) are a main focus of current cognitive-behavioural OCD research, there is also a renewed interest in INC feelings and "not just right experiences" with an inability to achieve "closure" concerning actions/perceptions. This study systematically examines the association of OCD symptom dimensions with INC and HA in a large clinical OCD sample (n=202). Hierarchical linear multiple regression analyses controlling for anxiety, depression and symptom severity demonstrated a unique association of symmetry/ordering and checking (but not of contamination/washing and obsessional thoughts) with INC, and of obsessional thoughts and checking with HA. Thus, in contrast with symmetry/ordering (predominantly INC-related) and obsessional thoughts (predominantly HA-related), checking was motivationally heterogeneous, i.e., associated with INC and HA to a comparable and substantial degree. Contamination/washing failed to show a unique association with HA in two of three analyses, and with INC in all three analyses. Symptom severity uniquely contributed to INC in two of three analyses, but not to HA. Clinically, our results indicate that a conceptualization of OCD as an anxiety disorder is too narrow.

The OCI-R is a psychometrically sound and valid self-report scale measuring the major symptoms of OCD on six dimensions: Checking, Washing, Ordering, Hoarding, Obsessing, and Neutralizing. Information is needed on its ability to discriminate OCD from depression. In this study, reliability and convergent, divergent, and known-groups validity of an authorized German version were examined in 381 patients with OCD, other anxiety and depressive disorders. Confirmatory factor analyses replicated the original six-factor structure in each sample. Moreover, results indicated good convergent, divergent, and known-groups validity for the full scale and the subscales in each sample, only a slight construct overlap between OCD and depression, anxiety, pathological worry, and perfectionism, and the relationships of the subscales with obsessive-compulsive personality features supported its construct validity. Previous findings for the original scale were replicated and extended in a different cultural context. However, the domains Neutralizing and Obsessions need further development.

Introduction: The English original version of the OCI-R is a brief, psychometrically sound scale measuring the major symptoms of patients with obsessive-compulsive disorder (OCD) on six dimensions: checking, washing, ordering, hoarding, obsessing and neutralizing. It has good convergent and discriminant validity and is sensitive to treatment effects. A German OCI-R version has not been examined until now., Method: Reliability and validity of an authorized German version of the OCI-R were examined in a sample of 175 patients with OCD. The patients were diagnosed by experienced psychotherapists via an interview that utilized the International Diagnostic Checklists. Other measures for anxiety, worry, depression and perfectionism were used to determine convergent and discriminant validity., Results: The full scale and five of six subscales had excellent internal consistency and "Neutralizing" had satisfactory internal consistency. A confirmatory factor analysis (SEM) replicated the original factor structure. All global fit indices suggested a good fit for the model. The local fit indices showed an excellent fit for 5 subscales and an acceptable fit for "neutralizing". The German version has good to excellent convergent validity and good divergent validity for the full scale and the subscales., Conclusion: The good results of the Foa et al.-study have been replicated in a German sample of patients with OCD. The German version of the OCI-R proved to be a reliable and valid self-report measure of obsessive-compulsive symptoms and appears to measure OCD quite independently from anxiety, worry, depression and perfectionism.

This paper describes clinically relevant aspects of incompleteness experiences in obsessive-compulsive disorder (OCD) (feelings of incompleteness concerning the self, "not just right" experiences and inability to achieve "closure" concerning actions/perceptions, compensatory urge to achieve "just right" feelings) and reviews empirical results and important research areas (frequency, association with symptom-based subtypes, motivational heterogeneity within subtypes, harm avoidance and incompleteness as basic OCD elements, sensation-based perfectionism, and relation to tic-related OCD and dissociative processes, especially depersonalisation/derealisation). Neurobiological explanations, biographical reconstruction, and treatment approaches are briefly summarised. It is emphasised that cognitive-behavioural methods tailored to OCD as an anxiety disorder must be modified considerably for the treatment of incompleteness-motivated OCD.

Purpose: For the first time an evaluation of standard anesthetic monitoring was performed according to the guidelines of the Austrian Society for Anesthesiology, Resuscitation und Intensive Care Medicine (OGARI)., Methods: A questionnaire was delivered to all medical institutions performing anesthesia in Austria. A descriptive statistical evaluation was performed on all returned and completed questionnaires., Results: Generally, there is a high standard in compulsory monitoring and in PACU (actual compliance > 99%/85.8%). Supplemental equipment is required for disconnection alarm and measurement of inspired oxygen concentration (actual compliance: 98.3%/98.9%). Furthermore, measurement for inspired concentration of volatile anesthetics and relaxometry (actual compliance 68.7%/47.3%) has yet to be completed. University departments and regional hospitals have comparable standards (82.2% vs. 79.6%)., Conclusions: For the first time an Austrian-wide evaluation of anesthetic monitoring investigated the compliance with the 1992 recommendations of the Austrian Society of Anesthesiology, Resuscitation and Intensive Care Medicine. The data demonstrate that these recommendations including the anesthetic monitoring equipment have already been implemented to a high degree.

This paper comprises a compilation of five papers, originating from Austria, Belgium, Denmark, Portugal and the United Kingdom. It describes the actions and measures taken for the transposition of the medical devices directives as well as the implementation of a vigilance system. It also includes aspects of the implementation of a trans-European system for data exchange in the field of medical device vigilance system.