Article
Materials Science, Multidisciplinary
Bernhard Viernstein, Tomasz Wojcik, Ernst Kozeschnik
Summary: A new state parameter-based user-subroutine is presented for finite-element software packages to simulate microstructure-dependent stress-strain relations. Well-established precipitation kinetics, strain hardening, and strengthening models are condensed for computational efficiency while maintaining their predictive capabilities. The framework includes main strengthening mechanisms, and with this novel user-subroutine, the microstructure evolution of various thermo-mechanical treatments on the finite element mesh can be calculated.
Article
Materials Science, Multidisciplinary
Tae-Rim Kim, Hyo Yeong Ahn, Yun Hak Kim, Seog-Young Yoon, Chi-Seung Lee
Summary: This study investigated the nonlinear behavior of polyurethane foam (PUF) under various conditions. A elastoviscoplastic constitutive model was adopted and discretized using an implicit time integration algorithm in ABAQUS. Parameter determination method was used to identify material parameters, allowing for the prediction of PUF's macroscopic material response.
MECHANICS OF MATERIALS
(2021)
Article
Materials Science, Multidisciplinary
D. Kim, R. Jiang, P. A. S. Reed
Summary: The effects of microstructure and oxidation on fatigue crack initiation and early propagation processes were investigated in RR1000 turbine disc alloy with different gamma' and carbide distributions. Fatigue tests were conducted at 650 degrees C in air using three-point bending and trapezoidal waveform loading. Intergranular features were clearly observed in both gamma' variants, with fatigue cracks initiating at grain boundaries containing Co-rich oxides and interfaces between carbides and grain boundaries due to oxidation damage under applied loading. Enhanced fatigue crack growth rates were attributed to significant intergranular crack initiation and frequent crack coalescence events, particularly where more continuous carbides exist at the grain boundary.
JOURNAL OF MATERIALS SCIENCE
(2023)
Article
Engineering, Chemical
Akshat Agha, Fadi Abu-Farha
Summary: One of the main challenges in the joining of multi-material components is the assessment of residual stresses in the adhesive bond. This study presents a numerical modeling approach that can predict these residual stresses and provide insights for decision making. The approach uses a multi-physics modeling package and is validated through experiments and simulations. Design guidelines related to adhesive selection and mechanical fixations are proposed as a result of the study.
INTERNATIONAL JOURNAL OF ADHESION AND ADHESIVES
(2022)
Article
Engineering, Mechanical
Dao-Hang Li, Ming Li, De-Guang Shang, Alok Gupta, Wei Sun
Summary: The proposed unified viscoplastic constitutive model combined with a physically-based damage variable can effectively model the cyclic elastic-viscoplastic behavior of the material at high temperature, by considering factors such as dislocation density and martensitic lath width.
INTERNATIONAL JOURNAL OF FATIGUE
(2021)
Article
Engineering, Mechanical
M. S. Baharin, S. Abdullah, S. S. K. Singh, M. K. Faidzi
Summary: This study investigates the delamination effect on the metal sandwich panel under constant spectrum loading. The results show that sandwich panel with dimple core design obtained better fatigue life value compared to solid core panel, which can improve sandwich panel's bonding strength and reduce the risk of early delamination.
ENGINEERING FAILURE ANALYSIS
(2022)
Article
Nuclear Science & Technology
K. Premjit Singh, Alpesh Patel, Kedar Bhope, Sandeep Rimza, Mayur Mehta, S. S. Khirwadkar
Summary: This paper presents an overview of experimental research on the vacuum brazing procedure for joining tungsten-based refractory materials, tungsten alloy, and SS316L at high temperatures. The study involves the use of selective brazing fillers and the Gleeble machine for high-temperature vacuum brazing. The brazed joints have undergone testing and characterization to evaluate their quality.
FUSION ENGINEERING AND DESIGN
(2023)
Article
Engineering, Mechanical
Lahouari Benabou
Summary: This study trains a neural network to predict the response of a viscoplastic solder alloy based on a reduced data set, accurately describing the behavior of the material within specific temperature and strain rate ranges. The neural network model is implemented in the finite element code Abaqus for simulating material behavior, showing good agreement with the physical viscoplastic model of Anand. However, limitations in predicting transient effects during strain rate jumps or temperature changes are identified and discussed.
JOURNAL OF ENGINEERING MATERIALS AND TECHNOLOGY-TRANSACTIONS OF THE ASME
(2021)
Article
Thermodynamics
Sreeja Sadasivan, Senthil Kumar Arumugam, Mahesh C. Aggarwal
Summary: This research work presents a computational modeling of multi-phase flow through an asymmetric exhaust hood, focusing on the effects of wetness on the pressure recovery capacity of a steam turbine exhaust hood. The findings indicate that wetness enhances the pressure recovery capacity of the exhaust hood.
PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART A-JOURNAL OF POWER AND ENERGY
(2021)
Article
Chemistry, Physical
Qiushuang Wang, Wenyou Zhang, Shujun Li, Mingming Tong, Wentao Hou, Hao Wang, Yulin Hao, Noel M. Harrison, Rui Yang
Summary: Ti-24Nb-4Zr-8Sn (Ti2448) is developed as a metastable beta-type titanium alloy for biomedical applications. Cylindrical samples of Ti2448 have been manufactured using the PBF-EB technique, and the influence of thermal history on microstructure has been analyzed through computational and experimental methods. The research shows that aging time and temperature can lead to variations in the alpha '' phase content in the manufactured samples.
Article
Engineering, Manufacturing
Brett D. Ellis, Hasan Haider, Matthew W. Priddy, Anirban Patra
Summary: This research developed a computational materials design framework for Mo-Si-B alloys for gas turbine blade applications, addressing the limitations of traditional materials development methods. The framework utilized finite element simulations, analytical models, and the inductive design exploration method to determine robust feasible domains for alloy design, with results indicating a maximum feasible temperature and specific volume fractions for different phases.
INTEGRATING MATERIALS AND MANUFACTURING INNOVATION
(2021)
Article
Materials Science, Multidisciplinary
Pichler Philip, Klunsner Thomas, Marsoner Stefan, Krobath Martin, Knabl Wolfram, Schatte Juergen, Bienert Christian, Ecker Werner
Summary: The aim of this study was to investigate the time-dependent visco-plastic behavior of the MHC alloy under stress-relieved condition. Cyclic strain-controlled low cycle fatigue experiments were conducted at different temperatures. The results showed the softening ability of the MHC alloy during cyclic loading, especially at high temperatures. The strain rate sensitivity of the stress response and the stress relaxation behavior were also examined.
INTERNATIONAL JOURNAL OF REFRACTORY METALS & HARD MATERIALS
(2023)
Article
Engineering, Manufacturing
Zhiyang Yu, Kristina Shea, Tino Stankovic
Summary: This study investigates the feasibility of using a multi-material, flexible chain mail sheet for the design of an additively manufactured artificial spinal disc, and demonstrates its ability to reproduce natural behaviors and anisotropy.
3D PRINTING AND ADDITIVE MANUFACTURING
(2022)
Article
Physics, Fluids & Plasmas
Jun Yao, Yufeng Yao
Summary: The study found that for a small horizontal circular pipe, the liquid film formed on the inner walls exhibits non-uniform distributions and is thinner at the top surface. Computational Fluid Dynamics (CFD) faces challenges in predicting the formation of the liquid film on the pipe walls due to inaccurate two-phase flow models. A user-defined function subroutine (ANNULAR-UDF) was developed in this study to simulate CFD modeling and capture the flow behavior, flow pattern formation, and other characteristics in validation against experiments.
Article
Engineering, Mechanical
Federico Lo Presti, Marwick Sembritzky, Benjamin Winhart, Pascal Post, Francesca di Mare, Alexander Wiedermann, Johannes Greving, Robert Krewinkel
Summary: This study investigates the operation of gas turbines under unstable conditions by simulating low-frequency disturbances introduced by periodic load variations. The results show that temperature fluctuations persist in the last rows of the turbine, affecting its performance. Additionally, the early detection of combustor failures is possible by analyzing the characteristic temperature fluctuations.
JOURNAL OF TURBOMACHINERY-TRANSACTIONS OF THE ASME
(2022)
Article
Engineering, Mechanical
Jordi Loureiro-Homs, Per Almroth, Frans Palmert, David Gustafsson, Kjell Simonsson, Robert Eriksson, Daniel Leidermark
Summary: The impact of crack closure effects on crack growth behavior was studied on Inconel 792 specimens under high temperatures, revealing that crack closure has a primary influence on crack growth behavior for this material. The crack closure behavior was successfully modeled using numerical simulations, including creep.
INTERNATIONAL JOURNAL OF FATIGUE
(2021)
Article
Computer Science, Interdisciplinary Applications
H. Andersson, L. J. Holmberg, K. Simonsson, D. Hilding, M. Schill, T. Borrvall, E. Sigfridsson, D. Leidermark
Summary: This study expands on a previously developed co-simulation method to simulate the dynamic behavior of sealing gap regions in hydraulic percussion units. The results show that dynamic gaps lead to a decrease in leakage flow, as deformed structures generate smaller clearances.
SIMULATION MODELLING PRACTICE AND THEORY
(2021)
Article
Materials Science, Multidisciplinary
Prabhat Pant, Filomena Salvemini, Sebastian Proper, Vladimir Luzin, Kjell Simonsson, Soren Sjostrom, Seyed Hosseini, Ru Lin Peng, Johan Moverare
Summary: Process parameters in laser-based powder bed fusion (LBPF) have a significant impact on part quality. This study investigated the influence of different scan strategies on the properties of complex L-shape parts made from Inconel 718 alloy. The results showed that the re-melting strategy could significantly reduce surface residual stress, while the sectional scanning strategies resulted in porosities at the interfaces.
MATERIALS & DESIGN
(2022)
Article
Engineering, Mechanical
Jordi Loureiro-Homs, Per Almroth, Frans Palmert, David Gustafsson, Kjell Simonsson, Robert Eriksson, Daniel Leidermark
Summary: The crack growth behavior of CM 247 LC alloy was investigated under out-of-phase TMF and isothermal tests. Plasticity-induced crack closure was identified as the main mechanism, and an analytical model was proposed to approximate crack closure effects.
INTERNATIONAL JOURNAL OF FATIGUE
(2022)
Article
Materials Science, Multidisciplinary
Thomas Lindstrom, Daniel Nilsson, Kjell Simonsson, Robert Eriksson, Jan-Erik Lundgren, Daniel Leidermark
Summary: This study investigates and models the mechanical response of an additively manufactured nickel-based combustor alloy subjected to thermomechanical fatigue (TMF) loadings. The study found that the orientation of the material affects its mechanical properties. A constitutive model is developed to accurately describe the material's response under TMF conditions.
MECHANICS OF MATERIALS
(2022)
Article
Engineering, Multidisciplinary
H. Andersson, L. J. Holmberg, K. Simonsson, D. Hilding, M. Schill, D. Leidermark
Summary: In this study, a developed co-simulation method was used to simulate wear in a hydraulic percussion unit. The simulation results showed good agreement with experimental results, indicating the potential of the simulation method in predicting wear and seizure in hydraulic percussion units.
INTERNATIONAL JOURNAL OF MODELLING AND SIMULATION
(2023)
Article
Engineering, Mechanical
Stefan B. Lindstrom, Johan Moverare, Daniel Leidermark, Hans Ansell, Zlatan Kapidzic
Summary: The study adapts the OSR incremental fatigue damage model for high-cycle fatigue in specimens with stress-raisers in AA7050-T7, showing good agreement across different conditions. By integrating fatigue life for an aircraft load spectrum, the predictive capability of the model is demonstrated.
INTERNATIONAL JOURNAL OF FATIGUE
(2022)
Article
Engineering, Mechanical
Ahmed Azeez, Robert Eriksson, Viktor Norman, Daniel Leidermark, Johan Moverare
Summary: Exploring crack growth behavior is crucial for accurate fatigue life predictions. In this study, cracked specimens were tested under strain-controlled out-of-phase thermomechanical fatigue conditions. Higher minimum temperature resulted in faster crack growth rates, while the addition of dwell times showed no significant effects. Crack closure was observed in all tests, and the addition of dwell times and change in minimum temperature had little to no effect on crack closure stresses.
INTERNATIONAL JOURNAL OF FATIGUE
(2022)
Article
Engineering, Mechanical
Thomas Lindstrom, Daniel Nilsson, Kjell Simonsson, Robert Eriksson, Jan-Erik Lundgren, Daniel Leidermark
Summary: The crack initiation life of a ductile additively manufactured nickel-based superalloy is studied and modeled for low-cycle fatigue and thermomechanical fatigue conditions up to 600 degrees C. A life prediction model accounting for the anisotropy and temperature cycle is developed, generating good agreements with experimental results. This research has important implications for understanding and predicting the fatigue life of the alloy.
FATIGUE & FRACTURE OF ENGINEERING MATERIALS & STRUCTURES
(2023)
Article
Engineering, Mechanical
Stefan B. Lindstrom, Johan Moverare, Jinghao Xu, Daniel Leidermark, Robert Eriksson, Hans Ansell, Zlatan Kapidzic
Summary: The study employs the Ottosen-Stenstrom-Ristinmaa (OSR) incremental fatigue damage model for assessing the fatigue life of integral airframes made from 7050-T7451 aluminum plates. Validation is done through variable-amplitude high-cycle fatigue experiments conducted on circumferentially notched axisymmetric specimens and a geometry resembling an aircraft fuselage frame with flanges, stiffeners, and web panels. The paper also discusses the modification of OSR model parameters to account for surface roughness and acceptable failure probability.
INTERNATIONAL JOURNAL OF FATIGUE
(2023)