bluuebunny/crossref_metadata_2025 huggingface dataset:
Se scarifier à l’adolescence : le pré-texte d’une souffrance
Authors: Matha Catherine
Published: January 2021

L’auteur envisage les scarifications à l’adolescence comme relevant d’une protestation vitale soutenue par la mise à l’épreuve du corps, dont l’adolescent utilise la force expressive. Ce langage du corps est envisagé comme prétexte , c’est-à-dire en tant que support d’une demande autrement inassumable ou indicible. Mais aussi comme pré-texte , c’est-à-dire comme pré-texte d’une souffrance empêchée d’emprunter la voie des mots dans une adresse à l’autre. Le corps affecté se fait appel en proposant un texte non encore advenu, rendant lisible (interprétable) la souffrance psychique. L’investigation de l’investissement des enveloppes corporelles et de la place de la fantasmatique masochiste au Rorschach et au tat d’adolescents se scarifiant, âgés de 14 à 17 ans, étaye et enrichit cette proposition.
Devenir parents : une situation de double bind social ?
Authors: Tettamanti Manuel , Widmer Éric D.
Published: January 2021

Dans l’approche systémique, la transition à la parentalité est vue comme un moment de crise nécessitant une réorganisation du système familial. Les changements accompagnant cette transition sont alors expliqués par une régulation relativement autonome de la dynamique intrafamiliale, une perspective dont l’insuffisance a été soulignée à la fois par les thérapeutes systémiciens et par les sociologues. Des études indiquent en effet que la répartition des rôles adoptés au sein du couple parental est en grande partie le reflet de contraintes sociales plus ou moins explicites. Notre hypothèse est que leur nature contradictoire relève d’une forme de double bind social. D’un côté, une répartition des rôles conçue comme un libre choix relevant de leur sphère privée et de leur responsabilité. De l’autre, un environnement institutionnel qui favorise l’adoption de pratiques familiales sexuées. Cette contradiction dans les attentes sociales et institutionnelles relatives à la transition à la parentalité contribue à une situation de tensions familiales qui, dans certains cas, conduit les familles à demander un soutien psychothérapeutique. Notre perspective est illustrée par la situation d’un couple vu dans le cadre d’un service de consultation clinique en Suisse francophone.
La psychothérapie des addictions
Authors: Tousseul Sylvain
Published: January 2021

Le fait de consommer un produit, même toxique, n’est pas une maladie, surtout dans une société dont le fonctionnement principal repose sur la consommation, mais ne pas pouvoir faire autrement que de le consommer est-il pathologique ? Pourquoi certains peuvent s’en passer pendant que d’autres deviennent dépendants ? Existe-t-il des prédispositions aux addictions ? Et leurs psychothérapies présentent-elles des spécificités ? Le présent article se propose de répondre succinctement à ces questions afin de comprendre en quoi les addictions constituent une maladie, quels sont les facteurs étiologiques, et pourquoi il est important de les prendre en compte dans la psychothérapie si l’on souhaite viser une guérison plus pérenne.
L’articulation du bilan projectif aux soins d’un auteur de violences sexuelles : une remise en mouvement par « transvasement »
Authors: Smaniotto Barbara , Réveillaud Marie , Camps François-David
Published: January 2021

Dans les champs de la psychiatrie, du social et même du politique, les sujets auteurs de violences sexuelles sont l’objet de toujours plus de demandes d’évaluation qui s’infiltrent jusque dans la pratique clinique. Cette contribution se demande en quoi le bilan projectif (Rorschach – Thematic Apperception Test [TAT]), inscrit dans le cadre d’un dispositif thérapeutique, offre-t-il un nouveau champ et une autre scène propices au dévoilement d’aspects traumatiques enkystés. Nous illustrerons notre propos à partir de la situation clinique d’un sujet auteur d’actes pédophiles accueilli dans un groupe de psychodrame. Enfin, nous proposerons la notion de « transvasement » pour décrire le processus qui se déploie entre , à travers et au-delà des espaces individuel, projectif et groupal et qui semble ici engager une relance des mouvements psychiques.
Génération charnelle et transmission du péché originel chez Thomas d’Aquin
Authors: Costa Iacopo
Published: January 2021

Cette étude explore la position de Thomas d'Aquin au sujet du rôle de la chair dans la transmission du péché originel. Elle montre la différence entre la position définitive de Thomas à ce sujet (notamment dans le De malo) et celle, plus proche d'Albert le Grand et de Bonaventure, qu'il avait soutenue dans son Commentaire des Sentences.
L’anatomie du corps ressuscité comme matrice anthropologique chez Thomas d’Aquin
Authors: König-Pralong Catherine
Published: January 2021

En enquêtant sur la nature du corps ressuscité, cet article montre que la théologie des mystères de Thomas d’Aquin abandonne les principes péripatéticiens de sa théologie spéculative et de sa philosophie. Le corps ressuscité manifeste la perfection de la nature individuelle en supprimant la nature spécifique. Se démarquant de longues traditions physicalistes (corpusculaires) initiées par les Pères de l’Église, Thomas d’Aquin conçoit le corps ressuscité comme un « vivant ». Pour l’au-delà, le modèle biologique aristotélicien se révèle cependant caduc, puisque les corps ressuscités, bien qu’ils « vivent », n’y sont plus ordonnés à la perpétuation et à la perfection de l’espèce. La réalité du paradis n’est plus celle de l’espèce, d’un tout qui serait plus que la somme de ses parties, mais celle de singuliers ressuscités comme âmes rationnelles informant des corps individuels, sans que soient réalisées les fonctions vitales dont l’homme fait l’expérience sur terre. L’anatomie du corps ressuscité fonctionne ainsi comme matrice anthropologique chrétienne maximisée, qui soustrait l’homme à l’ordre de la nature pensée sur un mode spéciste.
Forging Unique Paths: The Lived Experience of Hispanic/Latino Baccalaureate Nursing Students
Authors: Woodley Lisa K. , Lewallen Lynne P.
Published: January 2021

Background:

The purpose of this study was to describe the lived experience of Hispanic/Latino nursing students, as shared by new graduates of baccalaureate nursing programs in the southeastern United States.

Method:

This research used descriptive phenomenology with in-depth, private, semistructured interviews. Data were analyzed using inductive analysis methods consistent with Braun and Clarke.

Results:

Data analysis resulted in four main themes: Being an Edge Runner, Connections Matter, Looking Within, and We Are Not All the Same.

Conclusion:

Analysis revealed that the lived experience of Hispanic/Latino baccalaureate nursing students is complex and multifaceted. Fostering these students' connections within nursing, understanding their unique paths, and recognizing the individuality that each brings to the learning environment are key factors in promoting their success.

[
J Nurs Educ
. 2021;60(1):13–19.]
Social, Demographic, Spanish Language, and Experiential Factors Influencing Nursing Students' Cultural Competence
Authors: Abrams Matthew Phillip , Chalise Sweta , Peralta Heather , Simms-Cendan Judith
Published: January 2021

Background:

Development of culturally competent nursing students is a core objective in nursing education.

Method:

One hundred sixty nursing students completed an online survey assessing sociodemographic information, Spanish language, service-learning participation, and cultural competency.

Results:

Degree of participation in the multidisciplinary farmworkers clinic (
r
= .374,
p
= .013), federally qualified health center (FQHC) (
r
= .387,
p
= .032), and short-term international medical mission trip (
r
= .433,
p
= .021) was associated with higher cultural competency. Furthermore, several demographic factors including being a native Spanish-speaker (
p
= .022), female (
p
= .004), Latino (
p
= .045) or a student of low socioeconomic status (
p
= .026) were associated with higher cultural competency.

Conclusion:

Participation in service-learning opportunities involving care for minority and disadvantaged communities, whether required or voluntary, was correlated with higher cultural competency scores, as long as the students' experiences involved direct patient care responsibilities. These findings highlight the need for identifying more diverse opportunities for service-learning and more diverse direct patient care opportunities to foster students' cultural competence.

[
J Nurs Educ
. 2021;60(1):29–33.]
Communicating and Coaching in Spanish for Chronic Care
Authors: Martinez Glenn A. , Parés-Avila José A. , Graham Margaret , Stauber Leah , Szalacha Laura , Menon Usha
Published: January 2021

Background:

Language barriers affect millions of health care consumers each year in the United States. One in five U.S. residents over the age of 5 years speaks a language other than English.

Method:

A multidisciplinary team consisting of applied linguists and nurse educators developed a graduate elective for nursing students who demonstrated a minimum Spanish proficiency level. The course was organized around three core content components: management of type 2 diabetes, motivational interviewing competencies, and strategic communication in Spanish. Course activities included discourse analysis, simulated mini-conversations, and standardized patient simulations.

Results:

A multidisciplinary team-teaching approach was ideal in assisting students to develop culturally sensitive clinical language skills.

Conclusion:

Language concordance is imperative to providing quality health care to non-English–speaking patients. Health care providers must be able to demonstrate empathy, an understanding of cultural dynamics, and the ability to provide care to non-English–speaking patients.

[
J Nurs Educ
. 2021;60(1):34–37.]
Using Critical Service-Learning Pedagogy to Prepare Graduate Nurses to Promote Health Equity
Authors: Bower Kelly M. , Alexander Kamila A. , Levin Mindi B. , Jaques Keilah A. , Kub Joan
Published: January 2021

Background:

Despite calls from professional organizations to prepare a nursing workforce with the requisite skills to address social determinants of health (SDOH), there is little guidance for nurse educators about how to actively promote student learning of these complex issues.

Method:

We applied a critical service-learning (CSL) pedagogy to enhance graduate public health nursing curriculum and support learner skill building in approaches to combat health disparities by addressing the underlying social conditions.

Results:

Course content and critical reflection activities were built incrementally across four courses and semesters to introduce and apply antioppressive frameworks, encourage students to examine their personal identities of privilege and oppression, and examine historical context and systems of power in public health settings.

Conclusion:

CSL supports student development of structural competence and their understanding of approaches that can dismantle inequitable systems by addressing SDOH that contribute to health disparities.

[
J Nurs Educ
. 2021;60(1):38–43.]
Addressing Ageism and Ethnocultural Diversity With a Photo Essay Project
Authors: Linz Sheila J. , Cresse Nancy J.
Published: January 2021

Background:

By 2050, the percentage of older adults in the United States will double. By 2060, nonmajority individuals will comprise nearly half of our older adult population. Therefore, nursing students must have learning experiences that prepare them to care for a diverse population of older adults when they enter practice.

Method:

Photo-elicitation and a photo essay project was initiated in an Aging and Health in Global Communities course in which 75 students created and presented photo essays of a diverse group of older adults.

Results:

Through spending time with older adults to create a photo essay, students ably portrayed lives rich in meaning and ethnocultural heritage.

Conclusion:

The natural intersection of aging and diversity that occurred in the photo essays enlightened students to the rich experience of age and the similarities and unique differences in the lives of the older people portrayed.

[
J Nurs Educ
. 2021;60(1):44–47.]
Clinical Reasoning: Adapting Teaching Methods During the COVID-19 Pandemic to Meet Student Learning Outcomes
Authors: Wyatt Terri , Baich Valerie A. , Buoni Charlotte A. , Watson Alison E. , Yurisic Victoria E.
Published: January 2021

Background:

The COVID-19 pandemic impacted all aspects of health care, including nursing education. Senior nursing students saw the elimination of in-person clinical opportunities in the final months prior to graduation as health care facilities restricted access to essential personnel in an effort to minimize transmission of the virus and conserve personal protective equipment.

Method:

To fulfill course requirements, faculty created a COVID-19 assignment that implored students to research the most current infection control recommendations for COVID-19 and to describe the impacts of the virus on nursing care, patients, families, interdisciplinary collaboration, and public safety.

Results:

The COVID-19 assignment fostered clinical reasoning and encouraged personal reflection with application to practice. Students reported that the assignment greatly enhanced knowledge and awareness of COVID-19.

Conclusion:

This assignment was beneficial for transition to practice in the midst of a pandemic, and it can be easily replicated for any future emerging health care topic that may affect nursing education.

[
J Nurs Educ
. 2021;60(1):48–51.]
The microbial community structure of the Dupnisa cave in Kırklareli, Turkey
Authors: Doğruöz-Güngör Nihal
Published: January 2021

Cave ecosystems count to be extreme environments due to their stable temperature, darkness, high humidity rates, and limited organic materials. In this context, these ecosystems represent invaluable laboratories for microbiological studies. Although there are common features between the microorganism groups obtained from the culture-based microbiological studies conducted in the caves and the groups highlighted through molecular methods, the microorganism groups determined through this last method are richer. The detected microorganisms are variable depending on the characteristics of each cave. The aim of this study is to determine the microbial diversity in samples taken from 5 different regions (including regions visited by tourists) of Dupnisa Cave and to reveal the differences between these regions. This is the first microbiological study running in cave sediments of Dupnisa Cave System situated in the north-western of Turkey. In this study, using the Illumina MiSeq next-generation sequencing approach for analyses of Dupnisa Cave samples, 14 phyla and 298 genera as well as 2 phyla and 20 genera can be attributed to bacterial and archaea OTUs, respectively. Moreover, the bacterial community is dominated by the phyla Proteobacteria, Actinobacteria, Bacteroidetes, Gemmatimonadetes, Firmicutes, Nitrospirae, Chloroflexi and Acidobacteria distributed with 1 % and above. Archaeal community is represented by Thaumarchaeota and Euryarchaeota phyla. Proteobacteria is the most dominant bacterial phylum and Thaumarchaeota dominates the archaeal phyla. The highest number of types of bacteria according to Chao 1 richness estimation index were found at point AF (cave entrance / sediment), and that of types of archaea were found at point F2 (touristic area 2 / cave sediment). F2 was determined as the sampling point with the highest diversity of archaeal and bacterial genera according to Shannon-Wiener diversity index.
Assessment of karst geomorphosites on Kučaj and Beljanica mountains as a resource for the development of karst-based geopark
Authors: Petrovic Aleksandar Slavisa , Nikolić Dragana , Trnavac Bogdanović Dušica , Carević Ivana
Published: January 2021

Protection and promotion of geoheritage has been changing and improving in recent decades, in line with the growing research in this field. Some research papers specifically study geomorphological geoheritage and introduce a special term − geomorphosite. Karst geomorphosites present specific objects of geomorphological heritage. On Kučaj and Beljanica mountains there is the largest karst area in Serbia. The purpose of this paper is to select and evaluate the scientific value of karst geomorphosites of Kučaj and Beljanica. More than one hundred karst geomorphosites were analyzed. In order to achieve more adequate coverage and representation, they were grouped into 25 geomorphotypes in three major geomorphological components of the investigated area. The results of this analysis highlighted the most important natural potentials of this area for establishing a karst-based geopark. More than 20 geomorphotypes have a positive recommendation index, which provides a good basis for further geotourism analysis.
FTMP-Based Kink Deformation and Strengthening Mechanisms for Mille-Feuille Structures
Authors: Nawa Yuta , Hasebe Tadashi
Published: January 2021

Kink-strengthening for mille-feuille structures has attracted many attentions in recent years. This study aims at identifying the kink formation/strengthening mechanisms via numerical reproductions of emerging kink-like morphologies based on FTMP (Field Theory of Multiscale Plasticity)-incorporated FE simulations, considering the Rank1 connection, where the incompatibility-based relevant underlying microscopic degrees of freedom for kinking are introduced. The targeted phenomena here include an experimentally-observed unique feature recently reported based on the combined ND–AE (neutron diffraction - acoustic emission) technique, i.e., scale-free-like energy release before (precursor) and during kink formations. This study uses a Mg single crystal model with alternatingly aligned soft and hard layers in parallel to the basal plane under c-axis plane-strain compression, where the soft/hard regions are controlled by the values of the hardening ratio. Also, we assume that the kink mode is only active, while the basal, prismatic and pyramidal slip and the twin systems are not operative associated with the layered structure. From the simulated results, we confirm kink-like morphologies and the attendant significant misorientation in the basal plane angles. Also, the simulated results are demonstrated to exhibit power-law type distributions in the strain energy fluctuation from the early stage of deformation even before the massive emergence of kink-like regions, which are analogous to the above-mentioned ND–AE observations.
Mechanical Joining Utilizing Friction Stir Forming
Authors: Ohashi Takahiro , Nishihara Tadashi , Tabatabaei Hamed Mofidi
Published: January 2021

It is expected that the material ratio of steel for an automobile will decrease rapidly in next decade due to the rise of electric vehicles, and multi-materialization of parts will be promoted consequently. Hence, technologies for dissimilar materials joining have been studied by researchers successfully for recent years. The authors have studied dissimilar materials joining with utilizing friction-stir forming (FSF) approach. The FSF is a friction-stir process invented by Nishihara in 2002. In FSF, a substrate material was put on a die firstly. Next, friction stirring was conducted on the back surface of the material. The material then deformed and filled the cavity of the die due to high pressure and heat caused by the friction stirring. The authors utilized the FSF approach to generate mechanical joints between dissimilar materials. In this presentation, the author introduces various techniques for joining dissimilar materials with employing the FSF.
Metallurgy of Highly Wear-Resistant Indefinite-Chill Work Roll Materials for Hot Rolling Mills
Authors: Paar Armin , Aigner Michael , Beal Coline , Sommitsch Christof
Published: January 2021

Indefinite-chill materials are used as shell materials for cast work rolls for surface-critical applications in hot rolling mills. Besides a smooth surface quality, a low sticking tendency and low sensitivity against incidents in the rolling mill, the work rolls need the highest wear resistance possible. The microstructure of the indefinite-chill material consists of various carbides (cementite up to 40 area-%) and up to 5 area-% of graphite embedded in tempered martensite. To increase the wear resistance of this material group, the comparably soft cementite has to be replaced by more wear resistant carbides such as MC, M2C or M6C. This can be achieved by increasing the amount of carbide forming elements such as Nb, V, Mo, W or Cr. Nevertheless it is important to maintain a certain amount of graphite in the microstructure to avoid sticking to the rolled material and to lower the sensitivity against mill incidents. It is well known that high amounts of carbide forming elements limit the graphite precipitation and therefore a sophisticated alloying concept is required for this material type. Not only the effects of matrix elements such as Si, Mn, Ni and Co but also the effects of Cr, Mo, W, Nb and V were studied in an intensive research project. This work gives an insight in the results of the project based on the example of the effects of Si and Cr on the phase amounts and the composition of the cementite phase.
Anisotropy of Plastic Deformation in Hexagonal Metals
Authors: Paidar Vaclav , Čapek Jaroslav
Published: January 2021

Geometric aspects of the shear processes in hexagonal metals are analysed. They can be divided into three groups: those localized essentially between neighbouring atomic planes, occurring in narrow slabs along particular atomic planes, or covering a large crystal volume. Obviously, dislocation glide and deformation twinning are principal types of such processes. On the geometrical level, the dislocation slip as well as twin propagation are controlled by Schmid factors. Since the sample loaded by external stress can sometimes give way to fracture (cleavage) under tensile stress, it has to be also mentioned. The main aim of this work is to show only on geometrical grounds for which sample orientation which process is more likely to occur. More complex shear processes that take place during double twinning are also briefly considered. In polycrystals, the shear phenomena lead to texture formation when the processes that control the behaviour of materials may be those that act in a similar way in single crystals.
When 3D Printing Meets Tribological Demands - Surface Functionalization Technologies as Added Value of Existing and New Emerging Products
Authors: Panaitescu Ileana , Ripoll Manel Rodríguez , Katsich Christian , Hubmann Reinhard , Badisch Ewald
Published: January 2021

3D printed parts and components operate under specific conditions in demanding applications thus requiring additional surface functionality. From the tribological point of view, as-printed surfaces need to enhance their wear resistance or be able to control friction when sliding against other components. The overall focus is to develop a smart approach for functional component optimization through tribo-technical / technological optimization. In this work, the development of a hybrid 3D-printing process was realized by: (i) a combination of production technologies (hybridization), and (ii) customized surfaces by laser processing (functionalization). The focus is set on the increase in the wear resistance by the presence of hard and wear resistant particles embedded in a metallic matrix. For controlled friction behavior self-lubricating layers were deposited on the surfaces.
Effect of Nb on the Austenite Microstructural Homogeneity of Hot Rolled Rebars
Authors: Pereda Beatriz , Bastos Felipe , López Beatriz , Rodriguez-Ibabe J.M.
Published: January 2021

While the role of Nb in flat rolling of low carbon steels has been investigated in many works, the information about the use of Nb in rebar rolling of higher carbon grades is more limited. Rebar rolling presents differences relative to flat rolling that can affect the role of Nb, such as the application of higher number of rolling passes, higher strain rates, lower interpass times, and, consequently, enhanced adiabatic heating. Increasing the number of passes can contribute to austenite grain refinement. However, the high finishing temperatures in rebar rolling can lead also to significant austenite grain growth and microstructural heterogeneity development before phase transformation. This phenomenon will directly influence the final grain size and can also lead to the appearance of second hard phases in the final product. One of the options to avoid austenite grain growth is to add microalloying elements that retard grain growth kinetics, either in solid solution or as precipitates. This can open new roles for the application of Nb in rebar rolling. To analyze this, in this work laboratory torsion tests were performed with two 0.2%C steels microalloyed with two different Nb contents (0.029% and 0.015%). Soaking temperatures from 1100°C to 1250°C were applied to obtain different amounts of Nb in solid solution before grain growth study. The study shows that not only finish rolling temperature and cooling time, but also reheating temperature and the amount of Nb remaining in the form of undissolved precipitates are important factors controlling austenite grain growth.
Microstructure after Solution Annealing of the Nuclear Grade Austenitic Stainless Steel DIN 1.4970
Authors: Plaut Ronald Lesley , Padilha Angelo Fernando , Neto Flavio Beneduce , de Carvalho Leandro Gomes
Published: January 2021

The main objective of the present work was to characterize the phases that are present after solution annealing in the microstructure of the titanium stabilized austenitic stainless steel W.-Nr. 1.4970, developed as a candidate material for fast breeder reactor fuel cladding. The crystalline structure, chemical composition, quantity, size, morphology, and distribution of the phases present in the microstructure after solution annealing heat treatments were studied in detail with the help of several complementary techniques. Chemical dissolution of the matrix has been performed using the Berzelius solution and the extracted residue has been analyzed by X-ray diffraction in a high precision camera. Three phases have been observed and identified after solution annealing heat treatments performed in the 1090 to 1300 °C temperature range, namely: (Ti,Mo)C; Ti (N,C) and Ti4C2S2. The Ti-nitride and the Ti-carbosulfide did not dissolve in the steel matrix up to 1300 °C, on the other hand, the solubility of the (Ti,Mo)C raised strongly with temperature. A solution annealing heat treatment is recommended for the W. Nr. 1.4970 stainless steel.
Time-, Temperature- and Frequency-Dependent Viscoelastic Properties of a Curing Epoxy Adhesive
Authors: Geiss Paul Ludwig , Schumann Melanie
Published: January 2021

Thermoset adhesives convert from liquid to solid due to chemical reactions. Once cured, these adhesives carry the potential to create strong load-bearing joints, resisting even severe detrimental service conditions. In the progress of curing of a thermoset adhesive the viscoelastic properties of the resin and hardener formulation change as the chemical reaction proceeds. Gelation occurs once a continuous 3-dimensional network of polymer chains has been created. After gelation, the microstructure of the resin is fixed and further cure is affected by diffusion limitations [1]. Mastering of the curing kinetics and the physicochemical changes in the transition from the liquid to the solid-state is essential to reliably process adhesives in industrial applications. Rheological experiments in parallel plate configuration have become a well-established practice in investigating viscoelastic properties in the progress of curing. In practice, it has shown to be challenging to access the full range of viscoelastic parameters of thermoset resins with a low initial viscosity from the very beginning of the curing reaction to the post-cure consolidation of the vitrified polymer. This paper will discuss experimental methods and criteria for the viscoelastic analysis of curing thermoset adhesives and present experimental data of the time-, temperature-, and frequency-dependent viscoelastic properties of a curing thermoset epoxy in relation to the features of its time-temperature-transformation-diagram.
Microstructure Evolution during Multiaxial Processing of TA6V
Authors: Jalme Margaux Saint , Desrayaud Christophe , Favre Julien , Fabrègue Damien , Dancette Sylvain , Schuman Christophe , Lecomte Jean Sébastien , Archaud Etienne , Dumont Christian
Published: January 2021

Subtransus multiaxial hot forging of α+β Ti-6Al-4V (TA6V) titanium alloy with a β-transformed microstructure aims at obtaining an equiaxed microstructure through α phase globularization. The activation of mechanisms involved in microstructural evolution, such as globularization, depends on parameters such as time, temperature, strain and strain rate. It is also sensitive to the crystallographic orientation of α-lamellae. As a result, multiaxial processing of titanium alloys leads to significant microstructural gradients depending on thermomechanical conditions and initial microstructure. In this study, we focused on the effect of complex thermomechanical paths on microstructural evolutions. Thanks to the MaxStrain Gleeble device, we were able to reproduce such thermomechanical treatments to β-transformed TA6V samples. Stress strain fields obtained with finite element modelling of the MaxStrain test were compared to experimental microstructure gradients. This experimental method offers the opportunity to get closer to industrial open die forging conditions.
Internal Dislocation Density in Deformed GlidCop from X-Ray Line Profile Analysis
Authors: Sano Mutsumi , Takahashi Sunao , Shiro Ayumi , Shobu Takahisa , Nakada Kengo
Published: January 2021

Dislocation densities of GLIDCOP®, dispersion-strengthened copper with ultra-fine particles of aluminum oxide, were evaluated by employing the X-ray line profile analysis using the modified Williamson-Hall and modified Warren-Averbach methods. X-ray diffraction profiles for GlidCop samples with compressive strains applied at 200oC were measured with synchrotron radiation. The dislocation densities of GlidCop with compressive strain ranging from 0.6 to 4.3% were in the order of 3.2 × 1014–5.8 × 1014 m-2. The dislocation density increased with increasing the compressive strain within the measured strain range.
Effects of Peening Direction on Reverse Transformation Induced by Shot-Peening for Fe-33%Ni Alloy
Authors: Sato Hisashi , Tominaga Takuto , Chiba Tadachika , Moritani Tomokazu , Watanabe Yoshimi
Published: January 2021

Effects of peening direction on the reverse transformation induced by the shot-peening for the Fe-33 mass%Ni alloy with large amount of martensite (α’) are investigated. When the angle between the peened surface and the peening direction (Hereafter, peening angle) is 90 o, the reverse transformation occurs and subsequently martensitic transformation is induced by the shot-peening. On the other hand, in case of the peening angle of 30 o, only reverse transformation occurs. Furthermore, the volume fraction of austenite (γ) in the specimen after the shot-peening increases as the peening angle decreases. This means that the reverse transformation induced by the shot-peening is enhanced by decreasing the peening angle. Moreover, residual compressive stress around the peened surface increases as the peening angle decreases. Since the hydrostatic compressive stress decreases phase transformation temperature, the phase transformation temperature around the peened surface would be decreased by the shot-peening. Therefore, the reverse transformation behavior depending on the peening angle can be explained by the residual compressive stress due to the shot-peening.
The Effect of Long-Term Heating on Thermal Stability of Ultra-Fine Grained Titanium Alloy VT8M-1 Processed by Rotary Swaging
Authors: Stotskiy Andrey , Yakovleva Tatyana Vitalyevna , Dyakonov Grigory , Polyakov Alexander V. , Semenova Irina P.
Published: January 2021

The paper focuses on the analysis of microstructure and mechanical properties of the Ti alloy VT8М-1 (Ti-5.3Al-4.0Mo-1.2Zr-1.3Sn-0.2Si) in an ultrafine-grained (UFG) state subjected to a long-term annealing at a service temperature of (≤ 450°С). A rotary swaging (RS) was used to process an UFG state in the material. The precipitation of disperse silicides of S2 was observed after the deformation by RS. It has been shown that the UFG alloy retained its high level of thermal stability and enhanced mechanical properties after long-term annealing up to 500 hours. The role of disperse silicides in both strengthening and stability of mechanical properties in the alloy after long-term annealing is discussed.
Evaluation of Interfacial Thermal Resistance of Al-AlN Composites by Using Image-Based Calculation
Authors: Sugio Kenjiro , Kawata Takuya , Choi Yongbum , Sasaki Gen
Published: January 2021

Interfacial thermal resistance of Al-AlN composites was evaluated by comparing the measured thermal conductivity and the simulated thermal conductivity. Al-10vol.%AlN and Al-20vol.%AlN composites were fabricated by spark plasma sintering. Effective thermal conductivity was measured with the steady state thermal conductivity measuring device. Effective thermal conductivity was also simulated by using FE-SEM image and the measured relative density. Comparing the measured thermal conductivity and the simulated thermal conductivity, interfacial thermal resistance in Al-AlN composites was evaluated as about 1.27-6.2510-9 m2K/W.
Investigation of Bonding Strength of Al Solid Phase Diffusion Bonded Joint with Surface Treatment Using Electrolyzed Water
Authors: Tanaka Takuma , Shohji Ikuo , Kobayashi Tatsuya , Imai Hisashi
Published: January 2021

In this study, the effect of surface treatment of Al with alkaline (pH 10.5 and pH 12.4) and acidic (pH 3.7) electrolyzed water was investigated on bonding strength of solid phase diffusion bonded Al. Aluminum hydroxide and hydroxyl groups were appeared on the surface of Al which was treated with alkaline electrolyzed water of pH 12.4 at 323 K for 2700 s. It was found that such treatment is similar to the one with NaOH aqueous solution at 323 K for 30 s. For bonding strength, shear strength of the bonded Al specimens treated with electrolyzed water of pH 12.4 at 293 K for 3 s and 30 s were higher than that of the untreated specimen.
Study of High Temperature Properties of AlSi10Mg Alloy Produced by Laser-Based Powder Bed Fusion
Authors: Tocci Marialaura , Varone Alessandra , Montanari Roberto , Pola Annalisa
Published: January 2021

Additive manufacturing of Al alloys can represent an interesting solution for high-performance components in various industrial fields, as for instance the automotive and aerospace industry. Often, for these applications, the alloys are required to withstand exposure to high temperatures. Therefore, the investigation of the evolution of material properties with increasing temperature is of utmost importance in order to assess their suitability for this kind of applications. In the present study, tensile properties at high temperature were investigated for an AlSi10Mg alloy. Samples were manufactured by laser-based powder bed fusion in horizontal and vertical direction in order to examine the influence of building direction on material behavior. The samples were tested in as-built condition and after exposure to high temperature. Tensile tests were performed up to 150 °C and the effect of holding time at the test temperature was evaluated. Furthermore, the alloy was characterized by mechanical spectroscopy in order to evaluate the behavior of dynamic modulus with temperature and, thus, to provide a comprehensive characterization of the material behavior. It was found that the peculiar microstructure of the alloy produced by additive manufacturing is responsible for good high-temperature strength of the material up to 150 °C. The material also exhibits a good thermal stability even after holding at test temperature for 10 h.
Utilisation of Titanium and Titanium Dioxide as Scaffolds for Proliferating Coral Reef
Authors: Ueda Masato , Sawatari Chihiro , Takahashi Tomoyuki , Tsuruta Hiroaki , Tokushige Hidenobu , Hikosaka Hirohisa , Yonetsu Daigo , Ikeda Masahiko
Published: January 2021

Estimated 30 percent or more of coral reefs are now in danger of extinction by coastal construction increases and global temperatures rise. Several restoration techniques such as fragmentation, forming, Biorock have been developed in the past few years. In vertebrates such as mammals, osteoblast is known to form the bones composed of hydroxyapatite. Therefore, bone substitutional devices are generally surface modified to improve the adhesion of osteoblasts on the surfaces. Titanium dioxide film is often employed as the surface material for hard tissue substitutes made of titanium and its alloys. In hard corals, on the other hand, the soft tissue covered on the skeletons made of calcium carbonate has osteoblasts as well. The purpose of this work was to investigate the potential of titanium (Ti) and titanium dioxide (TiO2) as scaffolds for proliferating coral reefs by analysing the several interfacial reactions. The rods of pure Ti were anodised in aqueous phosphoric acid at a constant voltage of 80 V. The surfaces were confirmed to be anatase type TiO2. The coral fragments were kept in contact with the rods in a lab-scale aquarium with artificial seawater for several days. The colony of polyps vigorously expanded on the surfaces. Fragments of coral were placed on pure Ti, TiO2 coated pure Ti in Petri dishes and were reared in artificial seawater. Fine spherical precipitates of calcium carbonate with aragonite structure, which is the same inorganic substance as corals, were observed radially and regularly on the surfaces of TiO2. In addition, the adherence of planula larva to the sputtered TiO2 film was observed by using a QCM (Quartz Crystal Microbalance) method. The approach and adhesion of planula larva to the surface could be detected by monitoring the resonance frequency and resistance. The surfaces might have a great potential in coral reef regenerations.
Effects of Carbon Content Change on Growth of Compound Layer in Surface of Nitrided Steel
Authors: Umehara Takahide , Yuya Masato
Published: January 2021

When steel is nitrided, a compound layer mainly composed of iron nitrides, ε-Fe2~3N and the γ’-Fe4N phase, is formed on the steel surface. It is an extremely important industrial issue to clarify factors governing the formation of the compound layer during nitriding and to establish unified views on the mechanism of compound layer formation. Therefore, in order to clarify the effect of change in carbon concentration on the growth of the ε phase and the γ’ phase in the compound layer on nitrided steel, we evaluated the change over time in the concentration of the alloy elements in the surface layer, and the phases of the compound layer on nitrided steels containing various amount of carbon in the matrix. The results were that the change over time in the carbon concentration in the compound layer was mainly responsible for the change over time in the phases of the compound layer. Furthermore, it was discovered that the change over time in the carbon concentration distribution occurred because both increasing of carbon from the matrix to the compound layer, and decreasing of carbon from the surface of compound layer to the atmosphere. That caused the gradient change of chemical potential of carbon in the through-thickness direction of compound layer, and the phases of the compound layer were changed with the treatment time.
Surface Morphology of Refractory Metals Submitted to a Single Laser Pulse
Authors: Gaudio Pasquale , Montanari Roberto , Pakhomova Ekaterina , Richetta Maria , Varone Alessandra
Published: January 2021

The work investigates refractory metals (bulk W, W produced via plasma spraying, W-1% La2O3 and Mo) of interest as plasma facing materials in future nuclear fusion reactors. They have been irradiated by a single Nd:YAG laser pulse to simulate the effects of transient thermal loads of high energy occurring in a tokamak under operative conditions and then examined by SEM observations. In all the materials the laser pulse induces a crater in the central area of laser spot surrounded by a ridge due to movement of molten metal while in a more external area a network of cracks is observed. Diameter and depth of the crater, ablated volume and morphological features of the surrounding area exhibit differences depending on the specific metal, its physical and microstructural characteristics which affect vaporization, melting and heat propagation from the irradiated spot.
Finite Element Analysis of Surface Modification of Titanium Alloy Used for Hip Implant
Authors: Vulović Aleksandra , Warchomicka Fernando Gustavo , Filipović Nenad
Published: January 2021

Titanium and its alloys, especially Ti-6Al-4V have found application as hip implants due to their mechanical properties, excellent biocompatibility, and corrosion resistance. The use of cementless hip implants has increased over the years as it is thought that this type is more durable compared to cemented hip implants. Cementless hip implants have a porous surface that allows the bone to grow into it and form a strong bone–implant connection. The goal of this study is the use of Finite Element Method simulations to obtain information about how different types of surface topography of a TI-6Al-4V hip implant affect the shear stress, which is used to access the bone-implant connection. Finite Element Analysis is used to analyze the stress distribution in three simple surface modifications in a hip implant under different types of loads. The optimal surface modification out of these three is obtained based on the shear stress distribution, as it is known that lower shear stress promotes bone ingrowth. In this study, we have considered the interaction between cortical bone and implant surface. Material properties and boundary conditions used for the simulations have been adapted from literature.
Forming an Optically Transparent Graphene Film via the Transformation of C60 Molecules
Authors: Wada Yuri , Miyamoto Kaori , Yamada Takatoshi , Kuzumaki Toru
Published: January 2021

This study aims to optimize the production conditions for forming graphene directly on a quartz substrate, using a carbon 60 (C60) thin film as a solid carbon source. In this experiment, we focused on the relationships between the thickness of the C60 film and the nickel (Ni) catalyst film and the heat treatment conditions. As the thicknesses of the C60 and Ni catalyst films increased, high-crystallinity multi-layered graphene was formed, however the optical transparency of the graphene film decreased. Scanning Electron Microscopy (SEM) observations and Raman scattering spectroscopy showed that after changing the atmosphere of the heat-treatment from an argon (Ar) gas to an Ar+ hydrogen (H2) gas, the optical transparency of the graphene film was remarkably improved, due to the migration and vaporization of the Ni film, and due to etching of the multi-layered graphene.
Formation of Cemented Tungsten Carbide Layer with Compositional Gradient Processed by Directed Energy Deposition
Authors: Yamashita Yorihiro , Funada Yoshinori , Kunimine Takahiro , Sato Yuji , Tsukamoto Masahiro
Published: January 2021

In order to partially improve the wear resistance for dies and jigs, layer-forming technologies for adding cemented tungsten carbide is effective way as an additive manufacturing technique. As one of the layer-forming technologies, directed energy deposition (DED) has attracted much attention from industry. However, many cracks are usually observed inside a formed layer processed by the DED due to the difference of material properties between an iron-based substrate and a cladded cemented tungsten carbide layer. In terms of durability of the formed layer, the crack formation is not preferable as well. In this study, as an attempt to suppress the crack initiation and propagation in cladded layers processed by the DED, formation of compositionally graded cemented tungsten carbide layer was performed by inserting a layer with low to medium tungsten carbide content between the substrate and cemented tungsten carbide layer. At first, single layers of cemented tungsten carbide having various tungsten carbide content were formed on iron-based substrates by the DED processing to understand the relationships between the tungsten carbide content and the number of formed cracks. By considering these experimental results, the compositionally graded cemented tungsten carbide layers were optimized. It was revealed that the crack initiation and propagation could be suppressed by compositionally graded cemented tungsten carbide layers.
Elasto-Plastic Deformation of Heterogeneous Metallic Materials: An Experimental Approach with AlMg4Si10
Authors: Schöbel Michael , Tolnai Domonkos , Hofmann Michael
Published: January 2021

The increasing demand on thermo-mechanical strength, lightweight and formability in engineering applications require metallic materials with high sophisticated properties. Such functional alloys consist of heterogeneous composite-like microstructures, which are responsible for their stability in demanding service conditions (high temperature strength, low fatigue and creep resistance). External loads are distributed in between the phases of the alloys introducing high micro stress gradients, responsible for elastic and plastic deformation at the interfaces and micro crack initiation. Thus, the properties of such materials depend mainly on their phase shapes and 3D architectures leading to high stress gradients and elasto-plastic deformation under service conditions.This manuscript describes experimental studies on phase strain distribution for different heat treatment conditions in an AlMg4Si10 alloy. Neutron diffraction was used for strain measurement at an angle dispersive strain scanner with in-situ tensile test setup. Strain evolution under load and after unloading was measured to show elasto-plastic deformation behaviour in between the ductile α-Al matrix and stiff reinforcing Mg2Si and Si phases. The degree of plastification, its effect on micro stress gradients and its influence on crack initiation could be discussed and comparisons to other composite materials could be drawn.
Corrosion Resistance of Additive Manufactured Titanium Alloy Parts: The Effect of Recycled Powders
Authors: Acquesta Annalisa , Monetta Tullio
Published: January 2021

The possibility to reduce costs of the additive manufacturing (AM) technologies by using recycled powders is still an open question. The present paper aims to investigate the effect of using virgin and recycled powders on the corrosion resistance of Ti6Al4V titanium alloy additive manufactured parts. Although the study of the electrochemical behaviour of titanium parts produced by using AM is present in the literature, the corrosion resistance of samples manufactured using recycled powders is less investigated. This work would like to contribute to the deepening of this aspect. The experimental investigations have been carried out on as-built samples as well as on samples after mechanical polishing. The metallographic observations of additive manufactured samples showed a martensitic microstructure inside the prior β grain grew up as columnar structure. X-ray diffraction analysis revealed the presence of titanium oxide in rutile crystallographic phase. The electrochemical characterisation unveiled the lower corrosion resistance of the as-built additive manufactured components compared to the traditional counterpart. It also highlighted the effect due to the use of recycled powders when the bulk of the samples has been investigated.