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Tytuł:
Machine learning methods for diagnosing the causes of die-casting defects
Autorzy:
Okuniewska, Alicja
Perzyk, Marcin
Kozłowski, Jacek
Powiązania:
https://bibliotekanauki.pl/articles/29519775.pdf
Data publikacji:
2023
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
fault diagnosis
machine learning tools
neural network
classification trees
support vector machine
Opis:
The research was focused on analyzing the causes of high-pressure die-casting defects, more specifically on casting leakage, which is considered perhaps the most important and common defect. The real data used for modelling was obtained from a high-pressure die-casting foundry that manufactures aluminum cylinder blocks for the world’s leading automotive brands. This paper compares and summarizes the results of applying advanced modelling using artificial neural networks, regression trees, and support vector machines methods to select artificial neural networks as the most effective method to perform a multidimensional optimization of process parameters to diagnose the causes of die-casting defects and to indicate the future research scope in this area. The developed system enables the prediction of the level of defects in castings with satisfactory accuracy and is therefore a highly relevant reference for process engineers of high-pressure foundries. This article indicates exactly which process parameters significantly influence the formation of a defect in a casting.
Źródło:
Computer Methods in Materials Science; 2023, 23, 2; 45-56
2720-4081
2720-3948
Pojawia się w:
Computer Methods in Materials Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A numerical simulation study of mold filling in the injection molding process
Autorzy:
Baum, Markus
Anders, Denis
Powiązania:
https://bibliotekanauki.pl/articles/29520096.pdf
Data publikacji:
2021
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
injection molding
polymers
Hele-Shaw approximation
computational fluid dynamics
computing methods
Opis:
Injection molding can undoubtedly be regarded as one of the most widely used manufacturing processes for polymers (Guevara-Morales & Figueroa-Lopez, 2014). Furthermore, injection molding has found its way into various branches of industry (Fernandez et al., 2018) since it has several essential advantages over other processing techniques in terms of good surface finish, the ability to process complex parts without the need for secondary operations, and low cost for mass production. In order to find optimal process settings, it is necessary to gain a deeper insight into the filling process and the underlying physical phenomena, as well as a thorough understanding of the complex material behavior. In this context, the numerical simulation of the injection molding process is increasingly important. Therefore, the current contribution is dedicated to present a thorough comparative numerical study for the mold filling of an exemplary thin-walled mold geometry, including a realistic non-Newtonian viscosity model for the polymer melt. For the numerical simulation, the authors employ the commercial CFD software packages Cadmould 3D-F and ANSYS CFX. While ANSYS CFX is a well-established CFD software for numerical modelling of multiphysical phenomena, Cadmould 3D-F is a highly specialized and computationally efficient alternative suitable for certain geometric configurations in the context of injection molding. The present study is new in the sense that it demonstrates the equivalence of the considered software packages for the simulation of the injection molding process in thin-walled mold geometries.
Źródło:
Computer Methods in Materials Science; 2021, 21, 1; 25-34
2720-4081
2720-3948
Pojawia się w:
Computer Methods in Materials Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Comparing deterministic and statistical approaches for predicting “short can” defects in aluminium beverage can production
Autorzy:
Baran, Wojciech
Regulski, Krzysztof
Kąc, Sławomir
Milenin, Andrij
Powiązania:
https://bibliotekanauki.pl/articles/29519771.pdf
Data publikacji:
2023
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
short can
deterministic
analysis
statistical methods
predict
defect
reduce
decizion trees
Opis:
In the production of beverage cans, “short can” defects in the form of material discontinuities can occur during the deep drawing of cylindrical thin-walled aluminium products. These defects have a significant impact on production efficiency and scrap generation, and their occurrence is influenced by material and process properties. To determine the main influence of material on defect occurrence, two approaches were used: deterministic analysis of mechanical properties and microstructure, as well as statistical processing of production data using decision tree models. The latter approach was found to be more efficient, and a numerical tool was developed based on this approach to predict and reduce defect occurrence in the production process.
Źródło:
Computer Methods in Materials Science; 2023, 23, 2; 29-38
2720-4081
2720-3948
Pojawia się w:
Computer Methods in Materials Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Viscoelastic characterization of additively manufactured acrylonitrile butadiene styrene
Autorzy:
Witek, Szczepan
Powiązania:
https://bibliotekanauki.pl/articles/29519773.pdf
Data publikacji:
2023
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
fused filament fabrication
two-layer viscoplastic model
stress relaxation
ABS
Opis:
The main objective of this work was to characterize the viscoelastic properties of additively manufactured Acrylonitrile Butadiene Styrene based on tensile stress relaxation tests. The stress relaxation measurements were conducted with a temperature range of 25–100°C. The two-layer viscoplastic constitutive model was adopted to describe the elastic and viscous behavior of the investigated material. The model parameters were calibrated using an inverse analysis and stress relaxation data. The model’s predictive capabilities were assessed by comparing the model predictions with experimental data not included in the calibration process.
Źródło:
Computer Methods in Materials Science; 2023, 23, 2; 39-44
2720-4081
2720-3948
Pojawia się w:
Computer Methods in Materials Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Space-time Taylor-Hood elements for incompressible flows
Czaso-przestrzenne elementy Tylora- Hooda dla nieściśliwych przepływów
Autorzy:
Pacheco, Douglas R. Q
Steinbach, Olaf
Powiązania:
https://bibliotekanauki.pl/articles/29520293.pdf
Data publikacji:
2019
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
computational fluid dynamics
finite element method
space-time methods
incompressible flows
stable finite elements
obliczeniowa dynamika płynów
metoda elementów skończonych
metody czasoprzestrzenne
przepływy nieściśliwe
stabilna metoda elementów skończonych
Opis:
Space-time variational methods differ from time-stepping schemes by discretising the whole space-time domain with finite elements. This offers a natural framework for flow problems in moving domains and allows simultaneous parallelisation and adaptivity in space and time. For incompressible flows, the usual approach is to employ the same polynomial order for velocity and pressure, which requires the use of stabilisation techniques to compensate for the inf-sup deficiency of such pairs. In the present work, we extend to the space-time formulation the idea of the popular Taylor-Hood element for the (Navier-)Stokes equations. By using quadratic interpolation for velocity and linear for the pressure, in both space and time, we attain a stable finite element method which provides optimal convergence for pressure, velocity and stresses.
Przestrzenno-czasowe metody wariacyjne wymagają dyskretyzacji metodą elementów skończonych całej domeny przestrzenno czasowej i tym różnią się od metod wykorzystującej schematy kroków czasowych. To podejście dostarcza naturalnych struktur dla problemów przepływu w poruszających się obszarach i pozwala na równoczesne zrównoleglanie i adaptację zarówno w przestrzeni jak i w czasie. Typowym rozwiązaniem dla przepływów nieściśliwych jest zastosowanie tego samego stopnia wielomianu dla prędkości i ciśnienia, co wymaga wprowadzenia metod stabilizacji w celu skompensowania niedoboru infimum-supremum takich par. W niniejszej pracy rozszerzono sformułowanie przestrzenno czasowe o ideę elementu Taylora-Hooda dla równań (Naviera-)Stokesa. Poprzez zastosowanie kwadratowej interpolacji dla prędkości i liniowej interpolacji dla ciśnienia, zarówno w przstrzeni jak i w czasie, uzyskano stabilną metodę elementów skończonych dającą optymalną zbieżność dla ciśnienia, prędkości i naprężeń.
Źródło:
Computer Methods in Materials Science; 2019, 19, 2; 64-69
2720-4081
2720-3948
Pojawia się w:
Computer Methods in Materials Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Computational intelligence based design of biomaterials
Autorzy:
Vinoth, Arulraj
Datta, Shubhabrata
Powiązania:
https://bibliotekanauki.pl/articles/29520060.pdf
Data publikacji:
2022
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
biomaterial
design
modeling
optimization
computational intelligence
biomateriał
projekt
modelowanie
optymalizacja
Inteligencja obliczeniowa
Opis:
This paper presents an overview of the applications of computational intelligence techniques, viz. artificial neural networks, fuzzy inference systems, and genetic algorithms, for the design of biomaterials with improved performance. These techniques are basically used for developing data-driven models and for optimization. The paper introduces the domain of biomaterials and how they can be designed using computational intelligence techniques. Then a brief description of the tools is made, followed by the applications of the tools in various domains of biomaterials. The applications range in all classes of materials ranging from alloys to composites. There are examples of applications for the surface treatment of biomaterials, materials for drug delivery systems, materials for scaffolds and even in implant design. It is found the tools can be effectively used for designing new and improved biomaterials.
Źródło:
Computer Methods in Materials Science; 2022, 22, 4; 229-262
2720-4081
2720-3948
Pojawia się w:
Computer Methods in Materials Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Processes simulations with multiscale materials models using a dedicated interface
Autorzy:
Smyk, Grzegorz
Szeliga, Danuta
Powiązania:
https://bibliotekanauki.pl/articles/29520085.pdf
Data publikacji:
2021
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
multiscale modelling
material models
model integration
recrystallization
Opis:
The main goal of this work is the integration of in-house software with commercial numerical software based on the finite element method (FEM). The main idea is to develop a universal interface to perform process simulations with multiscale models. The interface allows the combination of external procedures with commercial software with minimum programmer’s work putting in integration. As an example, the model of material recrystallization of steel was implemented, added to the commercial application, and the software was tested for a process defined as a sequence of compression and cooling. The material model takes into consideration each type of recrystallization that occurs during a sequence of thermal and mechanical processing such as static recrystallization (SRX), dynamic recrystallization (DRX), and meta-dynamic recrystallization (MDRX). It allows the prediction of recrystallized volume fraction (X) and grain growth on each step of numerical simulation for each Gauss point in the computation domain. The presented multiscale model of process sequences not only allows to calculate microscale model parameters such as grain growth and recrystallized volume fraction, but also reflects the impact of the microscale model on macroscale parameters.
Źródło:
Computer Methods in Materials Science; 2021, 21, 4; 181-192
2720-4081
2720-3948
Pojawia się w:
Computer Methods in Materials Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Texture evolution in Mg during rolling with a change of deformation path – a modeling approach
Autorzy:
Sułkowski, Bartosz
Powiązania:
https://bibliotekanauki.pl/articles/29520073.pdf
Data publikacji:
2022
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
Mg
deformation path
modeling
texture
modelowanie
tekstura
Opis:
The weakening of strong textures in Mg alloys is a crucial factor in obtaining good quality final products that are less anisotropic. Considerable attention has been focused on experiments to find the optimal chemical composition of alloys or processing conditions. However, to reduce time-consuming experiments, texture simulations can help in specifying future research directions. In the present work, the texture evolution in rolled Mg and its alloys was studied using the viscoplastic self-consistent model. The texture simulations presented in the study cover unidirectional rolling, reverse rolling, and cross rolling of Mg and its alloys to check if the change in deformation path has an impact on the activation of non-basal slip systems. The results obtained in the study may help to design the best processing technology and reduce the mechanical anisotropy of magnesium alloys. Slip systems such as basal, prismatic, and pyramidal were taken into consideration. To reflect the effect of alloying elements on hardening, different values for critical resolved shear stress were considered. Pole figures and slip system activity were investigated to understand the texture evolution during rolling as the deformation path changes. It was found that cross rolling may be the most effective processing technology to reduce strong textures during the rolling of Mg alloys. To activate non-basal systems, critical resolved shear stresses and the Schmid factor must be modified. The former can be changed by increasing the processing temperature, proper alloying elements, or change in the strain rate sensitivity; the latter by changing the deformation path.
Źródło:
Computer Methods in Materials Science; 2022, 22, 2; 101-109
2720-4081
2720-3948
Pojawia się w:
Computer Methods in Materials Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Thermomechanical modeling on the crack initiation of NiTi shape memory alloy
Autorzy:
Jiang, Dongjie
Xiao, Yao
Powiązania:
https://bibliotekanauki.pl/articles/29520078.pdf
Data publikacji:
2022
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
shape memory alloy
martensitic transformation
crack initiation
thermomechanical coupling
Opis:
The fracture of shape memory alloys is distinct from that of conventional metals, owing to the coexistence and interaction of multiple special features such as martensitic transformation, dislocation-induced plasticity, thermomechanical coupling and others. In this paper, the impact of thermomechanical behavior upon the crack initiation of a NiTi shape memory alloy under Mode I loading is investigated numerically and verified experimentally. A constitutive model incorporating phase transformation, plasticity and thermomechanical coupling is established. Via backward Euler integration and finite-element implementation, the longitudinal strain, martensite volume fraction and temperature field in the vicinity of the crack tip are furnished. The effects of grain size and loading rate on J-integral are revealed. The grain size dependence of crack initiation is non-monotonic. For the samples with grain sizes of 1500 nm, 18 nm and 10 nm, the shielding effect takes place in front of the crack. Additionally, the anti-shielding effect is detected for samples with grain sizes of 80 nm and 42 nm. The parametric study shows that loading rate imposes limited influence on J-integral, which is attributed to a small scale transformation. The decrement of yield stress and the increment of transformation hardening modulus can alleviate the anti-shielding effect and arouse the shielding effect upon crack initiation. The presented results shed light on the design and fabrication of high toughness phase transformable materials.
Źródło:
Computer Methods in Materials Science; 2022, 22, 1; 31-42
2720-4081
2720-3948
Pojawia się w:
Computer Methods in Materials Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Modeling of temperature-dependent cyclic performance of superelastic NiTi shape memory alloy
Autorzy:
Xiao, Yao
Ju, Shuangyan
Lin, Jianping
Powiązania:
https://bibliotekanauki.pl/articles/29520080.pdf
Data publikacji:
2022
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
shape memory alloy
phase transformation
micromechanics
Opis:
In this paper, a three-dimensional micromechanical-based constitutive model is proposed to describe the temperature-dependent performance of a cyclic deformed superelastic NiTi shape memory alloy. The dominant texture of the specimen is prescribed as <111> direction along the longitudinal direction. Apart from martensitic transformation, various mechanisms regarding superelastic degradation are taken into consideration. In order to be extended from the single-crystal scale to the polycrystalline version, the constitutive model is implemented into finite element software. It is verified that the measured cyclic response of a superelastic NiTi is well reproduced by the presented approach. Furthermore, the predicting capability of the proposed model is verified by simulating the mechanical behavior of NiTi tube subjected to cyclic bending.
Źródło:
Computer Methods in Materials Science; 2022, 22, 1; 13-22
2720-4081
2720-3948
Pojawia się w:
Computer Methods in Materials Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A dedicated sensitivity analysis and optimization application for industrial processes
Autorzy:
Myczkowska, Kamila
Szeliga, Danuta
Powiązania:
https://bibliotekanauki.pl/articles/29520087.pdf
Data publikacji:
2021
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
sensitivity analysis
modelling of industrial process
optimization
model validation
cooling of rails
Opis:
The paper describes the architecture and the use case of the developed Modelbox system for sensitivity analysis (SA), uncertainty analysis (UA) and the subsequent optimization of industrial processes. The proposed solution addresses the most common practical and technical problems encountered by researchers and engineers when performing sensitivity analysis. It combines the functions from the numerical toolbox with a simulation management system. Maintaining usability and a good user experience while managing complex investigations of time-consuming industrial process simulations is a very important feature of the system. Several improvements were introduced to optimize the computation time of analysis/modelling tasks, including the automatization of distributed calculations, persistent, transparent caching of simulation data and duration estimations from collected statistics. The system has the ability to perform remote, parallel, asynchronous computations of both analytic algorithms and numerical simulations. The system is dynamically scalable horizontally by using serverless computing endpoints and thus it can be easily adapted to the user’s current needs in a flexible way. Modelbox provides web-based access to analysis/modelling tasks from sampling, SA/UA, optimization to metamodelling. It is extended with numerous interactive visualization components for effective results control. In addition, to access data from the completed analysis, the system supports convergence tracking for SA estimates and intermediate optimization results. The process of controlled cooling of rails was considered as a case study. The formulated optimization task was to find a combination of process parameters that ensures a minimum volume fraction of bainite along with required interlamellar spacing and optimal homogeneity of hardness. Different sensitivity analysis methods were used to evaluate the significance of all variables with respect to their influence on the model output.
Źródło:
Computer Methods in Materials Science; 2021, 21, 4; 219-232
2720-4081
2720-3948
Pojawia się w:
Computer Methods in Materials Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
An efficient Monte Carlo Potts method for the grain growth simulation of single-phase systems
Autorzy:
Maazi, Noureddine
Lezzar, Balahouane
Powiązania:
https://bibliotekanauki.pl/articles/29520251.pdf
Data publikacji:
2020
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
alloys
crystal growth
Monte Carlo simulation
microstructure
Opis:
The choice of the lattice sites to be reoriented in the Monte Carlo Potts algorithm for grain growth simulation is repeated in a non-homogeneous way. Therefore, some grains are favorably growing than others. This fact may seriously affect the simulation results. So a modified MC method is presented. Lattice sites are selected for reorientation one by one following their positions in the matrix in each Monte Carlo step (mcs). This approach ensures that the various selections of one lattice site within every mcs are eliminated, and no favorable growth of grains at the expense of others. The calculation time considerably decreases. The effect of real-time and physical temperature on the grain growth kinetics is discussed.
Źródło:
Computer Methods in Materials Science; 2020, 20, 3; 85-94
2720-4081
2720-3948
Pojawia się w:
Computer Methods in Materials Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Electrical and thermal analysis for the copper removal process in an electric furnace
Autorzy:
Zybała, Radosław
Golak, Sławomir
Sak, Tomasz
Madej, Piotr
Powiązania:
https://bibliotekanauki.pl/articles/29519766.pdf
Data publikacji:
2023
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
numerical modelling
copper removal
electric resistance furnace
contact resistance
Opis:
The article presents an electrical model of a resistance furnace with two electrodes encompassing the generation of Joule heat. The characteristic feature of this model was the consideration of contact resistance between the electrodes and the slag. A series of analyses were conducted based on this model. Firstly, the impact of contact resistance on current flow and Joule heat generation in the furnace was assessed, demonstrating its significant importance. A separate group of analyses focused on the spatial configuration of the furnace and its interaction with the aforementioned phenomena. The impact of symmetric and asymmetric electrodes immersion was analysed. In addition to the impact on current flow, the study also demonstrated the influence on the natural convection mechanism described by the proposed measures of the spatial non-uniformity of heat generation. The research showed that symmetric electrode immersion allows for the generation of more heat in the system at a constant voltage. Asymmetric electrodes immersion causes an increase in the non-uniformity of heat generation, which translates into a higher intensity of natural convection.
Źródło:
Computer Methods in Materials Science; 2023, 23, 4; 31-44
2720-4081
2720-3948
Pojawia się w:
Computer Methods in Materials Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The role of die definition in the numerical simulations of two-points incremental forming processes
Autorzy:
Perzynski, Konrad
Pawlikowski, Kacper
Madej, Łukasz
Powiązania:
https://bibliotekanauki.pl/articles/29520054.pdf
Data publikacji:
2023
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
two-points incremental forming
finite element method
additive manufacturing
Opis:
The main objective of this work is to investigate the influence of the definition of dies type in the finite element simulation of the two-points incremental forming processes (TPIF). Particular attention is on determining the effect of assigning elastic properties for the 3D printed dies or considering fully rigid on the final results. During the research, three different shapes of dies were analyzed. Simulation results in the form of sheet thickness distributions and measured forces are presented for comparison purposes.
Źródło:
Computer Methods in Materials Science; 2023, 23, 1; 5-12
2720-4081
2720-3948
Pojawia się w:
Computer Methods in Materials Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Grain size measurement using a semi-automatic calculation tool
Autorzy:
Mernache, Fatah
Sehisseh, Abdelaziz
Amrane, Amina
Hadji, Said
Melhani, Yasmine
Grine, Mohamed
Messai, Lakhdar
Powiązania:
https://bibliotekanauki.pl/articles/29520058.pdf
Data publikacji:
2023
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
image analysis
grain size
calculator tool
microstructure
Opis:
This paper focuses on the development of a semi-automatic calculation tool to measure the Mean Linear Intercept (MLI) grain size of ceramics and other materials. The calculation tool was first verified and validated by using a certified micro-ruler and literature microstructures. It was then used to investigate the grain growth of UO2 pellets elaborated under different conditions. The tool offers the advantage of accuracy as well as the ability to quantify microstructures obtained with poor image quality. The estimated measurement errors were found to be less than 1 μm. The developed tool, mainly for the purpose of time-saving, allowed us to follow the microstructure (grain size) evolution of the elaborated UO2 fuel with different additives.
Źródło:
Computer Methods in Materials Science; 2023, 23, 1; 27-34
2720-4081
2720-3948
Pojawia się w:
Computer Methods in Materials Science
Dostawca treści:
Biblioteka Nauki
Artykuł

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