The design and analysis of large casted parts present significant challenges due to their complex geometry. Finite Element (FE) modeling is a vital tool for understanding the performance of casted components. However, the computational requirements associated with these parts often lead to excessive processing times and resource utilization. This thesis aims to enhance the efficiency of the mid-surface model creation by developing an FE modeling approach suited explicitly for large casted components. The study begins by exploring the background of casted parts and their applications. A comprehensive analysis of modeling and meshing techniques is conducted, emphasizing their application to large casted components. Building upon this knowledge, different ideas are examined, leading to the proposal of a methodology combining CAD strategies for design features, hybrid meshing techniques, and approaches aimed at reducing FE modeling time to streamline the overall process.To validate the proposed approach, a series of case studies involving casted parts with varying levels of complexity are undertaken. Real-world casting process parameters are considered, highlighting the advantages and limitations in each ideation phase. The proposed methodology is tested and show cased to expert engineers to evaluate its efficiency and feasibility. Furthermore, the efficiency of the new approach is quantitatively evaluated in terms of processing time. The developed methodology offers engineers and researchers a powerful tool to accelerate the design process and optimize FE modeling time while managing computational costs. As industries continue to push the boundaries of size and complexity in casted part design, the insights and techniques presented in this thesis offer a valuable resource for addressing the various engineering challenges inherent in future endeavors. / Utformningen och analysen av stora gjutna delar innebär betydande utmaningar på grund av deras komplexa geometri. Finita Element (FE)-modellering är ett viktigt verktyg för att förstå prestandan hos gjutna komponenter. De beräkningskrav som är förknippade med dessa delar leder dock ofta till alltför långa handläggningstider och resursutnyttjande. Detta examensarbete syftar till att förbättra effektiviteten av skapandet av mittyteta modeller genom att utveckla en FE-modelleringsmetod som är specifikt lämpad för stora gjutna komponenter. Studien börjar med att utforska bakgrunden till gjutna delar och deras tillämpningar. En omfattande analys av modellerings-och diskret iseringstekniker genomförs, med tonvikt på deras tillämpning på stora gjutna komponenter. Med utgångspunkt i denna kunskap undersöks olika idéer, vilket leder till förslaget om en metod som kombinerar CAD-strategier för designfunktioner, hybridmodelleringstekniker och tillvägagångssätt som syftar till att minska FE-modelleringstiden för att effektivisera den övergripande processen. För att validera det föreslagna tillvägagångssättet genomförs en serie fallstudier som involverar gjutna delar med varierande nivåer av komplexitet. Verkliga gjutprocessparametrar beaktas, vilket belyser fördelarna och begränsningarna i varje idéfas. Den föreslagna metoden testas och visas upp för expertingenjörer för att utvärdera dess effektivitet och genomförbarhet. Dessutom utvärderas effektiviteten av det nya tillvägagångssättet kvantitativt i termer av handläggningstid. Den utvecklade metoden erbjuder ingenjörer och forskare ett kraftfullt verktyg för att påskynda designprocessen och optimera FE-modelleringstiden samtidigt som de hanterar beräkningskostnader. När industrier fortsätter att tänja på gränserna för storlek och komplexitet idesign av gjutna delar, erbjuder de insikter och tekniker som presenteras i denna avhandling en värdefull resurs för att ta itu med de olika tekniska utmaningarna som är inneboende i framtida strävanden.

Dagens planering och projektering av konstruktioner präglas av ett resursutnyttjande, miljömässigt och ekonomiskt tänk, där resultatet kan medföra brister med avseende på dynamiken. Därmed är det ytterst viktigt att skapa goda förutsättningar för noggranna beräkningsmodeller som i ett projekteringsskede kan representera konstruktionernas dynamiska beteende. I denna rapport utfördes en jämförelseanalys mellan en FE-modell och en fältmätning, där Folke Bernadottes bro har använts som underlag. Syftet är att presentera skillnader och likheter i naturliga frekvenser och modformer baserat på jämförelseanalysen, samt belysa några av de viktigaste faktorerna bakom dessa. Resultatet visade för en kalibrerad FE-modell 11 % genomsnittlig skillnad för de naturliga frekvenserna och 99 % överensstämmelse med avseende på modformerna, där den mest väsentliga parametern i modellen var upplagsvillkoren. / Today's planning and design of constructions is characterized by a resource utilization, environmental and economic thinking, where the result can lead to shortcomings with regard to dynamic behaviour. Thus, it is extremely important to create good conditions for accurate calculation models that in a design phase can represent the dynamic behaviour of the structures. In this report, a comparison analysis was performed between an FE-model and a field measurement, where Folke Bernadotte's bridge has been used as basis. The purpose is to present differences and similarities in natural frequencies and mode shapes based on the comparative analysis, and to highlight some of the most important factors behind these. The result showed for a calibrated FE-model an average difference of 11 % for the natural frequencies and 99 % agreement with respect to the mode shapes, where the most important parameter in the model was the support conditions.

Despite extensive previous studies, the peak metamorphic conditions within the 2.0-1.8 Ga Svecokarelian orogen remain unclear, particularly regarding the deformation and migmatization events occurring between 1.87-1.80 Ga within the Ljusdal lithotectonic unit. While earlier observations indicate granulite facies metamorphism, the exact metamorphic conditions and nature of these events are still unclear. This thesis aims to determine the pressure-temperature range associated with the peak metamorphic conditions by analyzing mineral assemblages in the leucogranite of Sörfjärden, located east of Gnarp, Sweden. Through optical microscopy and electron microprobe analysis, a complex mineral assemblage was identified, including alkali feldspar, plagioclase, garnet, quartz, biotite, sillimanite, and Fe-Zn-rich spinel, with accessory minerals such as monazite, zircon, and rutile. Secondary chlorite and kaolinite were also observed. Ternary-feldspar thermometry revealed crystallization temperatures of 750 ˚C. Thermobarometric modeling of the bulk rock chemical composition, using the software GeoPS, indicated peak pressure-temperature conditions of 2.0–2.4 kbar and 740–770 ˚C, defined by the peak mineral assemblage garnet, plagioclase, quartz, sillimanite, and spinel. Melt structures on biotite and alkali feldspar were inferred to have formed during the second migmatization event, suggesting that granulite facies conditions were reached during the first migmatization event. While these findings provide insights into the metamorphic history of the Svecokarelian orogen, further investigations into the influence of Zn on the produced models are warranted. Addressing the limitations of current thermodynamic models would improve our understanding of this complex geological system. / Trots omfattande tidigare studier är de metamorfa förhållandena i den Svekokarelska orogenesen (2.0–1.8 Ga) fortfarande oklara, särskilt gällande de deformations- och migmatiseringsprocesser som inträffade mellan 1.87–1.80 Ga. Även om tidigare observationer tyder på metamorfos med granulitfacies är de exakta metamorfa förhållandena hos och karaktären av dessa processer fortfarande osäkra. Denna studie syftar till att fastställa det tryck-temperaturintervall som är förknippat med de högsta graderna av metamorfos genom att analysera mineralsammansättningar i leukograniten i Sörfjärden, beläget öster om Gnarp, Sverige. Genom optisk mikroskopi och elektronmikrosonderingsanalys identifierades en komplex mineralsammansättning: alkalifältspat, plagioklas, granat, kvarts, biotit, sillimanit och Fe-Zn-rik spinell, där monazit, zirkon och rutil är accessoriska mineral. Klorit och kaolinit är sekundära. Ternär fältspatstermometri påvisade en kristalliseringstemperatur vid 750 ˚C. Termobarometrisk modellering av bergartens kemiska sammansättning med programmet GeoPS indikerade maximala tryck-temperaturförhållanden på 2.0–2.4 kbar och 740–770 ˚C; mineralsammansättningen under dessa förhållanden var granat, plagioklas, kvarts, sillimanit och spinell. Smältstrukturer på biotit och kalifältspat tolkades ha bildats under den andra migmatiseringen, vilket medför att granulitfacies uppnåddes under den första migmatiseringen. Fastän dessa resultat ger insikter i den Svekokarelska orogenesens metamorfa historia är det motiverat att vidare undersöka inverkan av Zn på de framställda modellerna. Att hantera begränsningarna i nuvarande termodynamiska modeller skulle förbättra vår förståelse av detta komplexa geologiska system.

The primary contributor to greenhouse gases emissions in the European Union is the road transport sector, accounting for over 70% of total emissions. In response to this environmental concern, the EU is working on implementing strict regulations aimed at reducing emissions by 45% by the year 2030, compelling manufacturers of heavy-duty vehicles to produce emission free alternatives. While vehicle electrification is a promising solution,it introduces a new challenge: the need for lighter vehicles becomes more increasing with the incorporation of powerful yet heavy battery systems. This work aims to study the possibility of substituting the steel bus frames with composite material frames with the dual objectives of reducing the overall weight of the bus and minimising its environmental footprint throughout the life cycle of the part. The most suitable composite materials, manufacturing processes and joining methods for the studied frames were investigated based on literature review and a list of requirements. Composite finite element analysis was performed to study the behaviour of the composite assembly when it is inserted into the steel bus model to simulate the real-life environment.  The analysis performed showed that composite frames can facilitate a mass reduction of over half of the steel frames weight. An unfailing structural behaviour of the laminate can be achieved using adhesive bonding as the joining method between the two distinct materials. At the same time, two significant needs were highlighted: the importance of laminate optimisation (in terms of different material properties, number of layers and orientations) both to reduce costs and to maximise the structural strength through effective and efficient material distribution and the importance of partitioning the composite structure in a cost beneficial way (when it comes to scrap levels and moulds complexity). / Den huvudsakliga bidragande faktorn för utsläpp av växthusgaser inom den Europeiska Unionen är vägtransportsektorn som står för över 70% av alla utsläpp. Som gensvar på detta bekymmer för klimatet jobbar EU på att implementera stränga regler som syftar till att minska utsläppen med 45% till år 2030, vilket tvingar tillverkare av tunga fordon att producera utsläppsfria alternativ. Fastän fordonselektrifieringen är en lovande lösning, introducerar den en ny utmaning: behovet av lättare fordon ökar i takt med införandet av kraftfulla men tunga batterisystem.  Syftet med detta arbete är att studera möjligheten att ersätta bussars stålramar med kompositmaterialramar med det dubbla målet att minska bussarnas totala vikt samt minimera deras klimatvtryck under ramarnas livscykel. Tillverkningsprocessen och sammanfogningsmetoderna för de studerade ramarna undersöktes baserat på litteraturgenomgång och en kravlista för att ta fram de mest lämpliga kompositmaterialen. Kompositfinit elementanalys genomfördes för att studera beteendet hos ihopsättningen av kompositen när det sattes in i stålbussmodellen för att simulera den verkliga miljön. Den genomförda analysen visade att kompositramar kan leda till en massreduktion på över hälften av stålramarnas vikt. Ett osvikligt strukturellt beteende hos laminatet kan uppnås genom att använda adhesiv bindning som sammanfogningsmetod mellan de två distinkta materialen. Samtidigt lyftes två betydande behov: vikten av att optimera laminatet (vad gäller olika materialegenskaper, antal lager och orienteringar) både för att minskakostnader och för att maximera den strukturella styrkan genom effektiv materialfördelning och vikten av att dela upp kompositens struktur på ett kostnadseffektivt sätt (när det kommer till avfallsniv ̊aer och gjutningskomplexitet).

[pt] A presente dissertação tem como objetivo analisar a quantificação do lucro da intervenção, partindo da convicção de que a utilização indevida do direito de um terceiro não pode jamais ser um bom negócio. Inicialmente, será demonstrado que o enriquecimento sem causa é o instituto mais adequado para lidar com situações em que uma pessoa se beneficia injustamente à custa de outra. Serão minuciosamente analisados os critérios que precisam ser atendidos para que se caracterize esse tipo de enriquecimento, como o aumento patrimonial do interveniente, a obtenção da vantagem à custa de outrem, a ausência de justa causa e a subsidiariedade do instituto. Em seguida, serão explorados os métodos objetivos para calcular o valor que deve ser devolvido ao titular do direito violado, apontando a inaplicabilidade da teoria do duplo limite aos casos de lucro da intervenção, bem como as razões pelas quais os valores pagos a título de reparação de danos extrapatrimoniais não devem ser abatidos do montante a ser restituído. Sustenta-se, ainda, a inadequação de compensar o lucro com o dano dentro do contexto de enriquecimento sem causa. Por fim, será discutido o papel da boa-fé e da má-fé na conduta do interventor, onde o trabalho explorará as divergências na doutrina sobre o tema, concluindo que se o interventor age de boa-fé deve restituir o valor de mercado da vantagem obtida e o lucro da intervenção deve ser repartido entre o interventor e o titular de direito, de forma proporcional à contribuição de cada um. Quanto à má-fé, conclui-se que, além do valor devido pelo uso do bem, o interventor deve restituir todo o lucro obtido com a intervenção. Essa abordagem proporcionará uma análise detalhada dos aspectos legais e éticos envolvidos na quantificação do lucro da intervenção, contribuindo para uma compreensão mais profunda do tema no contexto do Direito brasileiro. / [en] This dissertation aims to analyze the quantification of the disgorgement of profits, based on the conviction that the improper use of a third party s right can never be a good deal. Initially, it will be demonstrated that unjust enrichment is the most appropriate institute for dealing with situations in which one person benefits unfairly at the expense of another. The criteria that need to be met in order to characterize this type of enrichment will be thoroughly analyzed, such as the increase in the intervening party s assets, obtaining the advantage at the expense of others, the absence of just cause and the subsidiarity of the institute. Next, objective methods will be explored to calculate the amount that must be returned to the holder of the violated right, pointing out the inapplicability of the double limit theory to cases of profit from intervention, as well as the reasons why the amounts paid as reparation of moral damages must not be deducted from the amount to be refunded. It is also argued that it is inappropriate to compensate profit for damage within the context of unjust enrichment. Finally, the role of good faith and bad faith in the intervenor s conduct will be discussed, where the work will explore the divergences in the doctrine on the subject, concluding that if the intervenor acts in good faith he must restore the market value of the advantage obtained and the profit from the intervention must be shared between the intervener and the right holder, in proportion to the contribution of each one. As for bad faith, it is concluded that, in addition to the amount due for the use of the asset, the intervener must refund all the profit obtained from the intervention. This approach will provide a detailed analysis of the legal and ethical aspects involved in quantifying the profit from the intervention, contributing to a deeper understanding of the topic in the context of Brazilian Law.

Die Baugruppenbasierte Modellierung ist seit vielen Dekaden ein Standard in der CAD-Modellierung. Nur so lassen sich komplexe Baugruppen wirtschaftlich realisieren. Seit nun mehr als 10 Jahren wurde dieser Modellierungsansatz durch Meshparts in die Welt der FE-Modellierung übertragen. Bald steht in steht in der Meshparts-Software auch Permas als Solver zur Verfügung. Wir zeigen, welche Vorteile die neue Kombination aus Pre-, Postprozessor und Solver mit sich bringt. / Assembly-based modeling has been a standard in CAD modeling for many decades. It is the only way to realize complex assemblies economically. For more than 10 years now, this modeling approach has been transferred to the world of FE modeling by Meshparts. Soon, Permas will also be available as a solver in the Meshparts software. We show the advantages of the new combination of pre-processor, post-processor and solver.

As demands for alternative sources of energy increase over the coming decades, water electrolysis will play a larger role in meeting our needs. The oxygen evolution reaction (OER) component of water electrolysis suffers from slow kinetics. An efficient, inexpensive, alternative electrocatalyst is needed. We present here high-activity, low onset potential, stable catalyst materials for OER based on a hierarchical network architecture consisting of Fe and Ni coated on carbon fiber paper (CFP). Several compositions of Fe-Ni electrodes were grown on CFP using a hydrothermal method, which produced an interconnected nanosheet network morphology. The materials were characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD). Electrochemical performance of the catalyst was examined by cyclic voltammetry (CV) and linear sweep voltammetry (LSV). The best electrodes showed favorable activity (23 mA/cm², 60 mA/mg), onset potential (1.42 V vs. RHE), and cyclability. / text

<p>The work material in metal working operations always showssome kind of anisotropy. In order to simplify the theoreticalanalysis, especially considering bulk deformation processes,anisotropy is usually neglected and the material is assumed tobe isotropic. On the other hand, the analysis that consideredthe influence of anisotropy seldom incorporates the influenceof friction. For predicting the material flow during plasticdeformation and for predicting the final material properties ofthe product, adequate descriptions of both flow stress curvesand coefficients of friction have to be developed.</p><p>In the present work a number of experimental methods fordetermining the anisotropy have been utilized and compared:Yield loci, strain ratios (R-values) and establishing flowstress-curves in different directions. The results show thatthe yield loci measurements are weak in predicting anisotropywhen the material strain hardening is different in differentdirections. It is concluded that also the strain ration(R-value) measurements are unreliable for describinganisotropy. The most trustable and useful results were foundfrom multi-direction determinations of the flow stresses.</p><p>Three typical cases of ring upsetting conditions wereanalyzed by theory (3D-FEM) and experiments:</p><p>    An anisotropic ring, oriented 900 to the axis ofrotational symmetrical anisotropy. The friction coefficientwas the same in all directions</p><p>    An isotropic ring. The friction coefficient was differentin different directions</p><p>    An anisotropic ring oriented 00 to the axis of rotationalsymmetrical anisotropy. The friction coefficient was the samein all directions</p><p>The cases 1) and 2) reveal that the influence of anisotropyon the ring deformation is quite similar to that obtained bychanging the frictional condition. The case 3) exposes that ifthe material flow caused by anisotropy is incorrectly referredto friction, the possible error of the friction coefficient canbe as high as 80% for a pronounced anisotropic material. Amodified two-specimen method (MTSM) has been establishedaccording to an inverse method. Experiments were carried ascylinder upsetting. Here both ordinary cylinders were used aswell as so-called Rastegaev specimen. Also plane straincompression tests were utilized. The results show that MTSM isable to evaluate the validity of a selected mathematical modelwhen both the friction coefficient and the flow stress areunknown for a certain process. MTSM can also be used toestimate the friction coefficient and flow stress provided thatthe selected mathematical model is adequate.</p><p><b>Key words:</b>Anisotropy, friction coefficient, flowstress, modified two-specimen method and FE-analysis</p>

Dans les systèmes naturels, le fer influence fortement le comportement de polluants tels que les métaux lourds. Cette étude souligne le rôle des particules ferriques en tant que catalyseur des réactions d'oxydo-réduction, et le caractère réducteur du fer ferreux adsorbé sur ces particules. Malgré l'importance de Fe(lI) dans les systèmes naturels dépourvus d'oxygène, très peu de données étaient jusqu'alors disponibles sur cette adsorption. En laboratoire, les nanoparticules d' hématite ont été choisies comme "modèle" de colloïdes naturels. Le système hématite-Fe(II) a été caractérisé, les constantes de complexation de surface ont été obtenues par titrations potentiométriques et le suivi du potentiel d' oxydo-réduction a permis de déterminer le potentiel standard Eh ° de notre système. Les seules données d'adsorption de Fe(lI) sur a-Fe20 3 ont permIs de calculer un diagramme de prédominance Eh-pH en termes d'espèces de surface. L'étude de notre système redox nous a conduits aux conditions optimales (pH, [Fe(ll)t [U(VI)]t) pour observer la réduction de U(VI) par Fe(lI) en suspension. Un mécanisme en deux étapes est proposé, la première étape suivant une cinétique du premier ordre. Les résultats obtenus en laboratoire ont servi de référence pour l'étude d'un système naturel, le lac d'Aydat (Puy de Dôme), lac eutrophe saisonnièrement anoxique. En période de stratification, alors que l'hypolimnion est anoxique et riche en Fe(lI), l'adsorption du fer ferreux est étudiée et le caractère réducteur de Fe(lI) adsorbé vis à vis de l'uranium est confirmé. Cette étude sur des particules naturelles a permis d'expliquer le flux de l'uranium dû soit à l'adsorptton-coprécipitation soit à la réduction précipitation.

In this study the elastic properties of a fcc Fe0.87Mn0.13 random alloy are studied by ab initio calculations. Ground state lattice parameters and elastic properties are calculated with Density Functional Theory using the Exact Muffin-Tin Orbital method and the Coherent Potential Approximation. Several magnetic models, approximations and distortion techniques are evaluated for optimized results, which are obtained by a Disordered Local Moment model with the Frozen Core and Generalized Gradient approximations using volume-conserving distortions.  Conclusively the longitudinal sound velocities are calculated from second order elastic stiffness constants and visualized by two different codes. The importance of magnetism for elastic properties is confirmed, as is the usefulness of the optimized computational scheme; all quantities obtained via the scheme is in accord with earlier theoretical and experimental results. Volume-conserving distortions are found to be more precise than volume-altering for calculation of elastic constants but also to be highly dependent on the precision of bulk modulus determination. The two sound-velocity codes are in complete agreement.