Article
Metallurgy & Metallurgical Engineering
Wen-bin Jia, Xin Li, Zhi Chen, Kai Zhao, Lei Fang
Summary: This study proposes a viscoplastic constitutive model for nickel-based alloy under multiaxial loading, incorporating Lemaitre damage model and non-proportional hardening factor. Simulation results of stress-strain hysteresis loops under different conditions show that the model accurately predicts fatigue behavior and life of the alloy. Experiments and simulations confirm the validity and accuracy of the proposed model.
JOURNAL OF IRON AND STEEL RESEARCH INTERNATIONAL
(2021)
Article
Engineering, Geological
Zhi Yong Ai, Yong Zhi Zhao, Ye Cheng Dai, Zhen Zhao
Summary: This paper investigates the three-dimensional elastic-viscoplastic consolidation behaviors of transversely isotropic saturated soils, establishes relevant material models, provides a method for obtaining parameters, and validates the theory through numerical examples.
Article
Engineering, Mechanical
Jiawei Bai, Ke Jin, Yong Kou
Summary: In this paper, an elastoplastic constitutive model is proposed to describe the ratcheting effect with loading history. It introduces a loading history variable to record stress history variation during cyclic loading. An improved kinematic hardening rule based on Ohno-Wang model is established to simulate the ratcheting effect. A new memory evanescence term is introduced to capture the difference of yield stress evolution during ratcheting and strain-controlled cyclic loading.
INTERNATIONAL JOURNAL OF MECHANICAL SCIENCES
(2023)
Article
Materials Science, Multidisciplinary
Leo Thiercelin, Francis Praud, Fodil Meraghni, Eric Fleury
Summary: In this study, a new constitutive model is proposed to explain the thermally-activated hardening recovery mechanism in metallic materials. The model incorporates the concept of hardening recovery variable and includes high temperature dependencies for both elastic and viscoplastic properties. Experimental data from uni-axial tests on AISI 316L austenitic stainless steel at various temperatures and strain rates are used to validate the model, and additional experimental data shows good agreement with the simulated responses, demonstrating the predictive capabilities of the model.
MECHANICS OF MATERIALS
(2023)
Article
Engineering, Multidisciplinary
Ehsan Shafiei, Mahdi Saed Kiasat, Ever J. Barbero
Summary: A micro-meso-scale (MMS) model is proposed to predict the rate-dependent behavior of woven fabric (WF) composite considering material nonlinearity and 3D geometrical nonuniformity. Experimental rate-dependent tests on the epoxy matrix and unidirectional composite are conducted to measure model constants, and the mechanical properties and nonlinearity of stress-strain curves of the WF composite are successfully predicted and compared to additional experimental tests.
COMPOSITES PART B-ENGINEERING
(2021)
Article
Engineering, Mechanical
Dao-Hang Li, De-Guang Shang, Xiang Yin, Ming Li, Feng Chen, Guo-Qin Sun, Wei Sun
Summary: A new life assessment framework is proposed based on elastic-viscoplastic modeling and damage behavior for structural components under multiaxial nonproportional loading at high temperature. The framework utilizes a viscoplastic constitutive model to capture non-proportional hardening effect and a damage model to assess failure life comprehensively. Evaluation of the framework at 650 degrees C shows errors within a factor of 2 under proportional and non-proportional fatigue loadings.
ENGINEERING FAILURE ANALYSIS
(2022)
Article
Mechanics
Dariusz Skibicki, Lukasz Pejkowski, Aleksander Karolczuk, Jan Seyda
Summary: This study aims to verify the applicability of the Tanaka non-proportional isotropic cyclic hardening model under various multiaxial asynchronous loadings. The results show that the Tanaka model improves the performance of the Chaboche model and is applicable to asynchronous loading.
INTERNATIONAL JOURNAL OF SOLIDS AND STRUCTURES
(2022)
Article
Engineering, Electrical & Electronic
Xu He, Shaobing Wang, Yuexing Wang, Lu Liu, Yawei Dong, Yao Yao
Summary: The study investigates the viscoplastic behavior of solder material at different scales, focusing on the continuous accumulation of unrecoverable deformation in Sn-3.0Ag-0.5Cu alloy due to thermal stress at elevated temperatures. A novel phenomenological constitutive model is developed to describe the deformation of lead-free solder interconnections in microelectronic packaging, showing excellent numerical stability when compared with experimental data of bulk solder materials. Uniaxial compression experiments of spherical joint-scale granules were conducted to understand the strain-stress relationship, and the developed model accurately characterizes the viscoplastic compression deformation of Sn-3.0Ag-0.5Cu solder on joint-scale.
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
(2021)
Article
Materials Science, Multidisciplinary
Long Xue, De-Guang Shang, Dao-Hang Li, Yu Xia
Summary: An online notch elastic-plastic analytical method is proposed to estimate the multiaxial notch local elastic-plastic strains in real time, coupling with the modified pseudo stress criterion and Chaboche constitutive model. For Ramberg-Osgood material, a unified online accumulation method of equivalent plastic strain increment is introduced to consider non-proportional cyclic strain hardening. The proposed rapid and effective simulating algorithm is validated using experimental data of TC21 titanium alloy and SAE1070 steel notched specimens, with comparisons showing good agreement between simulated results and measured data under multiaxial irregular loading.
JOURNAL OF MATERIALS ENGINEERING AND PERFORMANCE
(2021)
Article
Engineering, Mechanical
Zhichao Wei, Steffen Gerke, Michael Bruenig
Summary: This paper introduces a modified anisotropic stress-state-dependent plastic-damage continuum model to predict the plastic, damage, and fracture behavior of metals under different loading conditions. Experimental and numerical validations are performed to verify the effectiveness of the model, using techniques such as digital image correlation and scanning electron microscopy.
INTERNATIONAL JOURNAL OF PLASTICITY
(2023)
Article
Engineering, Geological
Zhi Yong Ai, Jun Tao Yuan, Yong Zhi Zhao, Ye Cheng Dai
Summary: This paper proposes an incremental three-dimensional Nishihara model to describe the stress-strain relationship of soft soils, and verifies the effectiveness of the model through experimental data comparison.
ENGINEERING GEOLOGY
(2022)
Article
Computer Science, Interdisciplinary Applications
Guo-qing Cai, Yan-lin Su, An-nan Zhou, Feng-jie Yin, Ye-hui Shi
Summary: This paper presents a novel elastic-viscoplastic constitutive model for reproducing the time-dependent behavior of unsaturated soil. The model combines the theoretical framework of the Unified Hardening model and the Barcelona Basic Model with Perzyna's overstress theory. It considers the effect of loading history and suction, and accurately describes the shear, dilatancy, and compression behaviors of unsaturated soil with different initial void ratios and stresses. Experimental data validates the capability of the proposed model in reproducing the time-dependent behavior of unsaturated soil or soft rock.
COMPUTERS AND GEOTECHNICS
(2023)
Article
Computer Science, Interdisciplinary Applications
Jun Wu, Wei Wang, Ya-jun Cao, Shi-fan Liu, Qiang Zhang, Wei-jiang Chu
Summary: In this study, a novel nonlinear fractional viscoelastic-viscoplastic damage creep model is developed to describe the 3-stage creep behaviour of rock-like geomaterials. The proposed model consists of viscoelastic and viscoplastic parts, which consider the viscoelastic and viscoplastic responses at different time scales. The model shows a successful description of the full 3-stage behaviour and adequately predicts the delayed deformation caused by accelerated creep in the tunnel simulation.
COMPUTERS AND GEOTECHNICS
(2023)
Article
Computer Science, Interdisciplinary Applications
Yanlin Su, Guoqing Cai, Fengjie Yin, Yepeng Shan, Annan Zhou
Summary: This paper presents a novel elastic-viscoplastic constitutive model that takes into account particle breakage to reproduce the time-dependent behavior of coarse-grained soil. The model integrates the Unified Hardening (UH) model, the elastic-viscoplastic (EVP) model, and the overstress theory. The relationship between particle breakage and loading rate is established, and state variables associated with the critical state of coarse-grained soil are derived to consider both time and particle breakage. A three-dimensional elastic-viscoplastic constitutive model is constructed by combining a one-dimensional viscoplastic hardening parameter with a secondary consolidation coefficient considering particle breakage. The proposed model requires 19 parameters and effectively describes the influence of time-dependency and particle breakage on the shear, dilatancy, and compression behaviors of coarse-grained soil with different confining pressures or initial void ratios. Experimental data comparisons validate the model's ability to replicate the time-dependent behavior of coarse-grained soil.
COMPUTERS AND GEOTECHNICS
(2024)
Article
Engineering, Mechanical
C. Santus, T. Grossi, L. Romanelli, M. Pedranz, M. Benedetti
Summary: The study proposes an optimization method based on fitting the global properties of the cyclic curves to experimental data to determine the stress-strain behavior of materials under multiaxial cyclic loadings. The method provides an accurate description of the material behavior at a low computational cost. Experimental tests on various materials demonstrate the effectiveness of the proposed method.
INTERNATIONAL JOURNAL OF PLASTICITY
(2023)
Article
Engineering, Mechanical
Bingbing Li, Yiming Zheng, Gang Chen, Takamoto Itoh, Xu Chen
Summary: The effects of strain amplitude on the isothermal fatigue and thermomechanical fatigue behaviors of 316LN stainless steel were studied and the physical mechanisms for the evolution of cyclic stress response were revealed. The manifestations of dynamic strain aging, dependence on loading modes and influence on deformation properties were discussed. A change in the dominated damage mechanism occurred at a strain amplitude of approximately 0.27%, where the isothermal fatigue and thermomechanical fatigue life curves intersected. The maximum stress was found to be an appropriate damage parameter for life prediction with a scatter band of 1.5.
INTERNATIONAL JOURNAL OF FATIGUE
(2023)
Article
Materials Science, Composites
Yue Liu, Jikang Li, Yue Kuang, Yongzhong Zhao, Min Wang, Hongtao Wang, Xu Chen
Summary: In this paper, carbon nanotube-modified carbon fibre/polyimide (CF/CNTs/PI) multi-scale composites were prepared by introducing amino-functionalized multi-walled CNTs into a PI resin matrix using an ultrasonic dispersion method. The interlaminar properties of the prepared composites were comprehensively evaluated by double cantilever beam (DCB), end-notched flexure (ENF), and short seam shear (SBS) tests. The addition of 0.5wt.% CNTs increased the Mode I and Mode II interlaminar fracture toughness of the material by 50.21% and 61.74%, respectively, and the interlaminar shear strength (ILSS) by 42.85%. The mechanisms of CNTs bridging the crack tip and enhancing the fibre/matrix interface bonding ability were dominant in improving the interlaminar properties.
JOURNAL OF COMPOSITE MATERIALS
(2023)
Article
Materials Science, Composites
Jikang Li, Zheng Liu, Yajing Li, Yongzhong Zhao, Min Wang, Hongtao Wang, Xu Chen
Summary: Glass fiber reinforced plastic (GFRP) was fabricated by molding with phenolic resin as the matrix in this study. The distribution, tensile properties, creep performance, and damage mechanism of GFRP were systematically investigated. Results showed that horizontal specimens had better tensile properties, lower viscoelasticity, and excellent creep resistance. The fibers exhibited a 3D core-shell morphology with transverse isotropy. Load was carried by the fibers and damage was in the form of fiber fracture and pull-out in horizontal specimens. Random distribution and interweaving resulted in double fracture sections of fibers in vertical specimens. Load was carried by the interface and resin, and damage was in the form of fiber pull-out and interfacial debonding. The high viscoelasticity of the resin and weak interfacial bonding ability led to large creep deformation in vertical specimens. Additionally, the creep strain under different loads could be accurately predicted by Modified Time Hardening model.
POLYMER COMPOSITES
(2023)
Article
Nanoscience & Nanotechnology
Zongchi Wang, Shouwen Shi, Jingtai Yu, Bingbing Li, Yajing Li, Xu Chen
Summary: A cryogenic cyclic plastic strengthening method is proposed in this paper to improve the yield strength and maintain high elongation by changing the microstructure of the material.
SCRIPTA MATERIALIA
(2023)
Article
Mechanics
Xiao Han, Xingyue Sun, Xu Chen
Summary: A locally assembled stiffness matrix method is proposed as a novel solution process for global stiffness matrices in triangular meshes of the linear-elastic plane problem. Each nonzero submatrix after assembly is considered as the locally assembled stiffness matrix (LASM). By using an artificial neural network based on the same physics, the proposed method achieves good agreement with the conventional finite element method while reducing computation time and storage by 48.42% and 77.73% respectively.
Article
Materials Science, Multidisciplinary
Hailong Dai, Shouwen Shi, Jiahui Tang, Can Guo, Zuoliang Ning, Xu Chen
Summary: The effect of heat treatment on the stress corrosion cracking of Monel 400 alloy in hydrofluoric acid vapor was studied using cracking crystallographic analysis. Different heat treatment temperatures have varying effects on the SCC of the alloy, with heat treatment increasing grain size and reducing residual strain. Large grains promote slip and active dissolution, increasing SCC susceptibility.
Article
Engineering, Mechanical
Qingtong Wang, Bingbing Li, Jingwei Zhao, Takamoto Itoh, Xu Chen
Summary: Isothermal and thermomechanical fatigue tests were performed with different tension dwell times, and the cyclic stress response and stress relaxation behavior were analyzed using TEM and EBSD. The results showed that fatigue was the dominant mechanism for crack initiation and propagation in all creep-IF tests, leading to specimen fracture. However, in creep-TMF tests, when the dwell time increased to 1800 s, the dominant damage mechanism shifted to creep-fatigue interaction, resulting in intergranular fracture mode and a significantly shorter life. Additionally, a life prediction model based on tension strain energy was proposed.
INTERNATIONAL JOURNAL OF FATIGUE
(2023)
Article
Computer Science, Artificial Intelligence
S. V. Venkatakrishnan, Chris M. Fancher, Maxim Ziatdinov, Rama Vasudevan, Kyle Saleeby, James Haley, Dunji Yu, Ke An, Alex Plotkowski
Summary: Neutron diffraction is a useful technique for mapping residual strains in dense metal objects. In this paper, the authors propose an object adaptive sampling strategy to measure the significant points first and predict the next most informative positions to measure. They demonstrate the real-time measure-infer-predict workflow on additively manufactured steel parts, leading to faster strain mapping with useful real-time feedback.
MACHINE LEARNING-SCIENCE AND TECHNOLOGY
(2023)
Article
Materials Science, Multidisciplinary
Can Guo, Shouwen Shi, Hailong Dai, Xingyue Sun, Jingtai Yu, Xu Chen
Summary: The corrosion behavior of Monel 400 alloy in HF vapor and liquid phases was compared in this study. It was found that more severe corrosion occurred in the vapor phase, which was attributed to the difference in corrosion product layer. Specifically, a loose and porous fluoride layer was observed in the vapor phase, while a compact oxide layer was formed in the liquid phase. According to thermodynamic analysis, the formation of fluoride layer could be caused by higher O2 content, HF concentration, or corrosion product deposition in the vapor phase, with corrosion product deposition playing the dominant role.
Article
Materials Science, Multidisciplinary
Hailong Dai, Shouwen Shi, Can Guo, Zuoliang Ning, Yue Kuang, Xu Chen
Summary: The stress corrosion mechanism of Monel 400 alloy in HF vapor was investigated, considering the synergistic effect of HF vapor corrosion and dislocation sliding. The results revealed that oxygen-assisted corrosion in HF vapor worsens the fluorination effect and leads to severe fluorination degradation of Monel 400 alloy. The formation of CuF2 harms the Ni element in the matrix and results in denickelification. Dislocation sliding not only accelerates corrosion degradation but also facilitates the initiation of transgranular cracks by tearing the denickelification layer. A law of crack initiation based on the Schmid factor is proposed.
Article
Mechanics
Jinhui Feng, Zheng Liu, Shouwen Shi, Shaowu Feng, Gang Chen, Xu Chen, Qiang Lin
Summary: The embrittlement behavior of two modified 9Cr-1Mo steels in liquid LBE was investigated. The results showed that the modified steels had improved mechanical properties compared to the original steel, and the embrittlement mechanism was temperature-dependent.
ENGINEERING FRACTURE MECHANICS
(2023)
Article
Chemistry, Physical
Xiaoran Wei, Kun Zhou, Shaowu Feng, Shouwen Shi, Qiang Lin, Gang Chen, Kai Song, Xu Chen
Summary: The research on degradation and failure of proton exchange membrane (PEM) is essential for studying cell failure. Automatic crack propagation tracking is necessary to provide detailed data on PEM fatigue behavior. CrackTracker, a Transformer-based model, was proposed to meet the specific characteristics of PEM and achieve high-performance crack tracking. Detailed comparisons with four widely used models demonstrated the superiority of CrackTracker in accuracy, efficiency, and generalization performance. Its fast inference speed and accurate detection of PEM cracks make it valuable for process safety management.
JOURNAL OF POWER SOURCES
(2023)
Article
Multidisciplinary Sciences
Tianguo Zhou, Xingyue Sun, Xu Chen
Summary: This study proposes a physics-guided modelling method to improve the generalization of artificial neural network (ANN) models on the prediction of multiaxial irregular cases. By introducing prior physical knowledge into the ANN model, the method achieves satisfactory performance and better extrapolation ability in predicting fatigue life. Compared with conventional models, the prediction errors are significantly reduced.
PHILOSOPHICAL TRANSACTIONS OF THE ROYAL SOCIETY A-MATHEMATICAL PHYSICAL AND ENGINEERING SCIENCES
(2023)
Article
Nanoscience & Nanotechnology
Zongchi Wang, Shouwen Shi, Jingtai Yu, Bingbing Li, Yajing Li, Xu Chen
Summary: In this paper, the cryogenic cyclic plastic strengthening (CCPS) method was used to strengthen 304 austenitic stainless steel, resulting in a material that combined multiscale structure and transformation-induced plasticity (TRIP) effect. After strengthening, harder small α'-martensite particles were formed in the austenite coarse grains, leading to dynamic strain partitioning during uniaxial tension tests at room temperature. Furthermore, martensitic transformation occurred steadily throughout the strain range of the tensile tests. At room temperature, the characteristics of cryogenic transformation were maintained and the saturation value of the transformation was increased. The strengthened material exhibited an excellent combination of high strength and ductility at room temperature.
SCRIPTA MATERIALIA
(2023)
Article
Engineering, Multidisciplinary
Jikang Li, Zheng Liu, Yue Liu, Yongzhong Zhao, Min Wang, Hongtao Wang, Xu Chen
Summary: In this paper, carbon fiber reinforced plastic was prepared using phenolic resin as the matrix by the molding method. The distribution of fibers inside the material and its influence on tensile fracture mechanism and creep properties were investigated. The experimental results show that horizontal specimens with a large number of fibers parallel to the tensile direction exhibit more excellent tensile properties. The difference in tensile fracture mechanism of horizontal and vertical specimens affects the creep properties of CFRP. Modified Time Hardening model can accurately fit all experimental data. Creep curves can be predicted based on the model parameters.
INTERNATIONAL JOURNAL OF PRESSURE VESSELS AND PIPING
(2023)
