Phoenix National Laboratories’ Post

🔧 What Is Bulk Modulus, and Why Should We Care? Have you ever wondered why materials behave the way they do under pressure? The bulk modulus is the key to understanding how materials respond to volumetric changes—it measures a material’s resistance to compression. But there’s more to it than meets the eye. Did you know that the bulk modulus directly relates to Poisson’s ratio and places an upper limit on it? For materials to have a bounded bulk modulus, Poisson’s ratio must stay below 0.5. For example, rubber-like materials, with Poisson’s ratio of 0.49, come very close to this incompressibility limit! 🔑 Why does this matter? • Volumetric strain is directly tied to mean normal stress through the bulk modulus. • As materials approach incompressibility, special finite element models are needed to simulate their behavior accurately, especially in rubber and other elastomeric materials. Understanding this relationship helps engineers design materials and perform analyses that account for the complex interplay between strain and stress when Poisson’s ratio approaches its limit. In the PDF, derivations are based on isotropic linear elastic materials with small strains so that dilatation is approximated by the volumetric strain defined by the trace of the linear strain tensor. This post was inspired by this post: https://lnkd.in/eyPYM8vf demonstrating the behavior of Poisson's effect and the question and comments from: https://lnkd.in/efj4gTUR If you found this useful, please consider resharing ♻️ and comment below ⬇️. Thanks 🙏 #MechanicsMaterials #MaterialScience #FiniteElementAnalysis #PoissonsRatio #BulkModulus #SolidMechanics

🔗💻🔎 DOI: https://lnkd.in/dzitGPWu 🧑📖 Building a model of the abrasion grinding mechanism in a tumbling mill based on data visualization 👨⚖️ 🏫 ©️ Yuriy Naumenko, Kateryna Deineka, Serhii Zabchyk (National University of Water and Environmental Engineering , Ukraine) Keywords: #tumbling #mill, intra-chamber #loading, #grinding by #abrasion, #granular #temperature, #grinding #performance Abstract The object of this study is the grinding process in a tumbling mill when the mechanism of destruction by abrasion is implemented, which is caused by the mechanism of shear loading. The abrasive effect due to the impulse interaction during the mutual chaotic movement of granular particles in the shear layer of loading, characterized by the granular temperature, is taken into account. The task solved was determining the parameters of the shear interaction, which is caused by the difficulties of modeling and complexity of the hardware analysis of behavior of the internal loading in the mill. A mathematical model was built based on data visualization for the abrasion grinding mechanism. The power of the shear interaction forces was taken as an analog of the grinding performance. The initial shear characteristic was considered to be the average value of the shear velocity gradient in the central averaged normal section of the shear layer. The impact on productivity of the granular temperature and mass fraction of the shear layer and loading turnover was taken into account. The effect of rotation speed on performance was evaluated by experimental modeling at a chamber filling degree of 0.45 and a relative particle size of 0.0104. The maximum value of the energy and productivity of grinding by abrasion was established at the relative speed of rotation ψω=0.55–0.6. The results have made it possible to establish a rational speed when grinding by abrasion, ψω=0.5–0.6. This value is smaller in comparison with grinding by crushing ψω=0.55–0.65 and breaking ψω=0.75–0.9. The established effect is explained by the detected activation of the chaotic quasi-thermodynamic movement of particles of the shear layer at slow rotation. The model built makes it possible to predict rational technological parameters of the energy-saving process of fine grinding in a tumbling mill by abrasion.

Strength of Materials Practice Test: Question Set - 02 https://lnkd.in/duwrk5AK

What Happens During Yield At the atomic level in the elastic and plastic regimes. For all solids, increasing stress results in a linear increase in strain (this is called Hooke’s law). The crystal structure and other factors will influence how far the bonds can stretch. Metallic bonding allows atoms to reform bonds just as easily as they can break bonds. What ends up happening is that rows of atoms slip together, forming a dislocation. At the yield point (or upper yield point), the force required to move a dislocation is less than the force required to stretch atomic bonds, so dislocations move. Dislocation motion cannot be undone, which is why the material deforms permanently. If a material has both an upper and a lower yield point, it means that at first, there is not much for the dislocations to interact with. There is a lower yield point and a yield plateau. After the dislocation density reaches a certain amount, the dislocations begin to interact with each other, and strain hardening occurs.  #Materialscience, #Engineering

In this fascinating test, a small sample of a polymer material is subjected to stretching forces until it breaks. By measuring the force applied and the resulting deformation, scientists can determine important properties such as tensile strength, elongation at break, and modulus of elasticity. This information helps engineers design materials that can withstand different conditions and loads, ensuring safety and durability. #BritishScienceWeek #MaterialsScience #TensileTesting #Polymers #StrengthAndElasticity

✨I'm excited to share our latest publication in the 'Journal of Alloys and Compounds!' ✨ Our paper, "Compressive Mechanical Properties of Thermal Sprayed AlCoCrFeNi High Entropy Alloy Coating," delves into the unique properties of AlCoCrFeNi coatings. Using atmospheric plasma spraying, we achieved a 300 μm thick coating with a microstructure featuring a nickel solid-solution matrix and secondary phases. Key highlights include: - Superior yield strength of 963.14 MPa and compressive strength of 1005.58 MPa in the cross-sectional direction. - The presence of secondary phases and intermetallics acting as reinforcement, enhancing load-bearing capacities. - Insights into deformation mechanisms, revealing that phase and splat boundaries play a crucial role in failure modes. Dive into the details and discover how this research can influence future applications in high-performance environments! #Research #MaterialsScience #HighEntropyAlloys #Engineering #Innovation A special thanks to Animesh Basak for leading this research.

💡 #Newpaper in 2024 🌊 Title: Detection and Analysis of Corrosion on Coated Metal Surfaces Using Enhanced YOLO v5 Algorithm for Anti-Corrosion Performance Evaluation 🔑 Keywords: #metalcorrosion; #YOLOv5; #machinevision technology; corrosion #coatings; #marine environmental corrosion 🔗 More at: https://lnkd.in/d2wzGRqj 📜 Abstract: This study addresses the severe corrosion issues in the coastal regions of southern China by proposing an improved YOLO v5-GOLD-NWD model. Utilizing corrosion data from the National Center for Materials Corrosion and Protection Science of China, a dataset was constructed for metal-surface corrosion under different protective coatings. This dataset was used for model training, testing, and comparison. Model accuracy was validated using precision, recall, F1 score, and prediction probability. The results demonstrate that the proposed improved model exhibits better identification precision in metal corrosion detection, achieving 78%, a 4% improvement compared to traditional YOLO v5 models. Additionally, through identification and statistical analysis of corrosion image datasets from five types of coated metal specimens, it was found that powder epoxy coating, fluorocarbon coating, epoxy coating, and chlorinated rubber coating showed good corrosion resistance after 24 months of exposure. Conversely, Wuxi anti-fouling coating exhibited poor corrosion resistance. After 60 months of natural exposure, the powder epoxy coating specimens had the highest corrosion occurrence probability, followed by chlorinated rubber coating and epoxy coating, with fluorocarbon coating showing relatively lower probability. The fluorocarbon coating demonstrated relatively good corrosion resistance at both 24 and 60 months of exposure. The findings of this study provide a theoretical basis for enhancing the corrosion protection effectiveness of steel structures in coastal areas.

In this video, I guide you through constructing an embankment over dry and saturated soil, featuring advanced techniques like polymer cell integration for enhanced stability. Watch as we set up the model, create intricate layers of soil, and define various parameters for optimal performance. Learn about stress propagation, pore pressure variations, and how to visualize results effectively! Whether you're a beginner or looking to advance your simulation skills, this tutorial is packed with valuable insights! Don’t forget to like and subscribe for more engineering content! For more tutorials, visit us at: https://lnkd.in/g5EZjpwC Or email address: administrator@hyperlyceum.com #Abaqus #SoilModeling #EmbankmentConstruction #CivilEngineering #FiniteElementAnalysis #SimulationTutorial #EngineeringTips #StructuralEngineering #Polymer #StressAnalysis #PorePressure #EngineeringEducation #STEM

Creating a molality field in refractory material modeling involves defining the concentration of solute in terms of molality (moles of solute per kilogram of solvent). This is essential in high-temperature processes where precise chemical compositions are critical. To do this, you first need to understand your system's components and conditions. Identify the solute and solvent, typically a molten phase like slag or molten metal. Calculate the moles of solute and the mass of the solvent in kilograms to compute molality. In simulation software, create a field variable for molality and input the values throughout the model, ensuring it interacts correctly with other physical fields. This allows for accurate modeling of properties like viscosity and diffusion rates, essential for predicting the behavior of the refractory system under operational conditions. Read more: https://lnkd.in/dgxq5Cqz #MolalityModeling #RefractoryMaterials #HighTemperatureProcesses #ChemicalComposition #SimulationSoftware #FieldVariable #ViscosityPrediction #DiffusionRates #ToomaMinerals #OperationalConditions

mechanical properties model has been developed to quantitatively describe the relationship between selected mechanical properties, such as hardness, tensile strength, and elongation, and the microstructural features of ductile iron. The influence of the microstructural features of ductile iron, including graphite nodule count, nodularity, fraction of graphite, fraction of ferrite, and fraction of pearlite, on the fracture mechanism and the mechanical properties were discussed. The validation tests demonstrated that the mechanical properties of ductile iron can be predicted with reasonable accuracy through the equations developed in this research. The importance of this work is that, when coupling the mechanical properties model with a computational solidification model that includes microstructural evolution, not only average but also local mechanical properties of ductile iron castings can be predicted. mechanical properties is improved in annealing furnace. so be careful about annealing process.