Article
Nanoscience & Nanotechnology
Masayoshi Kumagai, Koichi Akita, Masatoshi Kuroda, Stefanus Harjo
Summary: The study found that the dislocation density of austenitic stainless steel increased with the number of plastic deformation cycles, but began to decrease after a certain number of cycles. The changes in different types of dislocations during cyclic loading significantly affected the crystal structure and flow stress.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2021)
Article
Nanoscience & Nanotechnology
Vibhor Atreya, Cornelis Bos, Maria J. Santofimia
Summary: This study identifies the characteristics of martensite that govern the extent of transformation-induced deformation in ferrite grains in DP steels. It was found that small austenite grains tend to transform into martensitic variants with a close-packed plane parallel relationship with adjacent ferrite grains, affecting the deformation of ferrite grains.
SCRIPTA MATERIALIA
(2021)
Article
Engineering, Mechanical
Kazuho Okada, Akinobu Shibata, Yasunari Takeda, Nobuhiro Tsuji
Summary: This study found that block boundaries in lath martensite structure are the primary initiation sites for fatigue cracks in as-quenched martensitic steel. The incompatibility of plastic strains between adjacent blocks was identified as the cause of initial fatigue crack formation at block boundaries, while plastic deformation along {0 1 1} slip planes also played a significant role in transgranular crack propagation.
INTERNATIONAL JOURNAL OF FATIGUE
(2021)
Article
Nanoscience & Nanotechnology
Q. Li, D. Y. Liu, F. K. Yan, N. R. Tao
Summary: The study revealed that the activation of alpha\prime-martensitic transformation in nanotwinned 316L stainless steel can enhance both fatigue strength and fatigue life in the low-cycle regime by effectively releasing stress/strain localization.
SCRIPTA MATERIALIA
(2022)
Article
Materials Science, Multidisciplinary
J. Tabin, K. Nalepka, J. Kawalko, A. Brodecki, P. Bala, Z. Kowalewski
Summary: A remarkable plastic flow instability is observed during tensile deformation of the commercial 304 stainless-steel sheet at room temperature. The occurrence of plastic flow instability in 304 is dependent on the strain rate and specimen gage length. Moreover, the enhanced strain hardening resulting from deformation-induced martensitic transformation facilitates the orderly propagation of the strain-localized band.
METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE
(2023)
Article
Nanoscience & Nanotechnology
Fumiyoshi Yoshinaka, Takahiro Sawaguchi, Susumu Takamori, Satoshi Emura
Summary: This study investigates the mechanisms of TRIP-enhanced ductility by analyzing the tensile deformation microstructure of Fe-15Mn-10Cr-8Ni-4Si alloy. The study found that there are three different TRIP mechanisms, including γ->ε, ε->α', and reverse ε->γ transformations, which play important roles in the excellent ductility of the alloy.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2022)
Article
Materials Science, Multidisciplinary
Kinga Nalepka, Blazej Skoczen, Rafal Schmidt, Marlena Ciepielowska, Elwira Schmidt, Robert Chulist
Summary: The evolution of microstructure and its relationship with fracture under complex load conditions at the temperature of liquid helium were investigated. Thin-walled cylindrical samples made of AISI 304 steel were subjected to tension combined with torsion. The torque caused buckling of the sample, resulting in folds and wells that differentiated the transformation conditions. Feritoscopic examinations and profilometer surface characterization revealed that martensite alpha ' initiated in the slopes of elevations where the highest shear stresses arose. The secondary phase exhibited a special cross-lamellar microstructure, which was uncovered through detailed studies using electron backscatter diffraction (EBSD) and synchrotron X-ray diffraction.
MATERIALS CHARACTERIZATION
(2023)
Article
Materials Science, Multidisciplinary
Masayoshi Kumagai, Masatoshi Kuroda, Takashi Matsuno, Stefanus Harjo, Koichi Akita
Summary: This study investigated the stress response of austenitic stainless steel using neutron diffraction and found that there is stress sharing between austenite and martensite. The actual stress in the martensite is about half of the assumed stress and the phase stress in the austenite, and the martensite contains a large compressive residual stress.
MATERIALS & DESIGN
(2022)
Article
Nanoscience & Nanotechnology
Aya Matsushita, Yoji Mine, Kazuki Takashima
Summary: The addition of nanotwin bundles in 304 metastable austenitic stainless steel enhances fatigue crack growth resistance by inhibiting brittle twin boundary separation and promoting detwinning and martensite formation during crack propagation.
SCRIPTA MATERIALIA
(2021)
Article
Metallurgy & Metallurgical Engineering
Thiago Santos, Daniele Chaubet, Tony Da Silva Botelho, Guillaume Poize, Brigitte Bacroix
Summary: The study investigates the microstructural characteristics and associated hardening state of three different martensitic stainless steels (CX13, XD15, and MLX17) subjected to various thermomechanical treatments for tribological applications. It is found that all treatments, including cementation, HF quenching, and Age Hardening, effectively produce hard surfaces. The transformation of martensite obeys the KS orientation relationship and results in twin boundaries, which is different from low C steels. A quantitative analysis of the EBSD microstructures proposes a quantification of various relative hardening contributions.
METALLURGICAL RESEARCH & TECHNOLOGY
(2023)
Article
Materials Science, Multidisciplinary
Vibhor Atreya, Jan Steven Van Dokkum, Cornelis Bos, Maria J. Santofimia
Summary: This study presents a novel methodology to quantify the transformation-induced strains in ferrite in dual-phase steel. The results show that neglecting the shear deformation associated with the martensitic transformation leads to significant underestimation in the prediction of transformation-induced strains in ferrite.
MATERIALS & DESIGN
(2022)
Article
Chemistry, Physical
Yuji Momotani, Akinobu Shibata, Nobuhiro Tsuji
Summary: The present study investigated hydrogen-related fractures in low-carbon martensitic steel at different deformation temperatures. The sensitivity to hydrogen embrittlement increased with decreasing temperature from 100 degrees C to 0 degrees C, but decreased further below 0 degrees C. The characterization of fracture surface types revealed a similar temperature dependence of hydrogen-embrittled surfaces to the sensitivity to hydrogen embrittlement. Qualitative discussion indicated that the degree of hydrogen accumulation peaked in the medium temperature range, consistent with the experimentally confirmed sensitivity to hydrogen embrittlement.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2022)
Article
Nanoscience & Nanotechnology
Qi Yang, Qidi Sun, Weitao Yang, Qingguo Hao, Xiaodong Wang, Bin Zhang
Summary: By investigating the two main deformation modes during low-cycle fatigue (LCF), the microstructural evolution, four-stage cyclic hardening behavior, and the reason for the superior LCF resistance of Fe-30.7Mn-4.3Si-1.8Al austenitic transformation-induced-plasticity (TRIP) steel were determined.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2021)
Article
Materials Science, Multidisciplinary
Wangzhong Mu, Moshiour Rahaman, Felix L. Rios, Joakim Odqvist, Peter Hedstrom
Summary: This study combines physically based modelling and machine learning to establish a predictive model for strain-induced martensitic phase transformation in austenitic steels, providing accurate predictions in a wide temperature and strain range. The model has the potential for further extension and can be applied in the design of steels and components.
MATERIALS & DESIGN
(2021)
Article
Nanoscience & Nanotechnology
Liyang Zeng, Xiangyu Song, Nailu Chen, Yonghua Rong, Xunwei Zuo, Na Min
Summary: This study investigates the TRIP effect in austenitic steels by simulating experiments and using microstructural characterization methods. The results show that different types of martensitic transformations are associated with changes in SHR at different stages of deformation, and the contribution of DAMAI effect on SHR is greater than that of SIMT effect.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2022)
Article
Engineering, Mechanical
Cheng Luo, Huang Yuan
Summary: In this study, the anisotropic low cycle fatigue behavior of nickel-base single crystal superalloy was investigated in different crystal orientations. Fractography analysis revealed the activated slip systems under tension and a virtual resolved strain energy model was proposed to describe the anisotropic fatigue behavior.
INTERNATIONAL JOURNAL OF FATIGUE
(2023)
Article
Engineering, Mechanical
Tinglian Zhang, Huang Yuan
Summary: This study investigated the mechanical properties and fatigue performance of laser melted mismatching nickel-base superalloys through multiscale experiments and computations. It was confirmed that the local strength degradation does not affect the macroscopic stress-strain responses and overall low-cycle fatigue performance due to the stress shielding in the remelting material. The stress shielding mechanism was quantitatively illuminated, and a critical shielding criterion was established.
INTERNATIONAL JOURNAL OF FATIGUE
(2023)
Article
Engineering, Mechanical
Lihao Huang, Huang Yuan, Haiyan Zhao
Summary: Lattice metamaterials are increasingly used in weight-critical applications, and additive manufacturing technology provides more design freedoms. A new homogenization method based on finite element methods was proposed for accurate modeling of the mechanical behavior of complex microstructures. The mapping relation between lattice and finite element mesh, as well as edge effects, were clarified and modeled. The homogenization approach showed high numerical accuracy and outperformed the classical continuum model.
INTERNATIONAL JOURNAL OF MECHANICAL SCIENCES
(2023)
Article
Engineering, Mechanical
Changhao Pei, Huang Yuan
Summary: This study investigated the anisotropic mechanical properties of IN718 superalloy in three different heat treatment states and three loading directions. The differences in mechanical performances were attributed to precipitation hardening and the impediment of dislocation motion from delta particles. Preferential epitaxial grain growth and resulting ⟨100⟩ texture were considered responsible for the anisotropic tensile strength. Weibull distribution and area-weighted grain diameter were used to characterize the grain distributions. Hall-Petch relation was established to correlate directional grain size and yield strength, illustrating the dominance of precipitates in strengthening mechanisms and the effects of subgrain boundaries.
FATIGUE & FRACTURE OF ENGINEERING MATERIALS & STRUCTURES
(2023)
Article
Engineering, Mechanical
Jiawei Xu, Huang Yuan
Summary: In recent investigations of thermal gradient mechanical fatigue (TGMF), it has been confirmed that the fatigue lives of materials are greatly affected by temperature gradients. Determining temperature gradients in thin-walled structures is always challenging. This study experimentally and computationally examined tubular specimens under different conditions. By improving the inverse heat conduction method, two models were developed that accurately predict temperature gradients in TGMF experiments with reasonable accuracy and versatility.
INTERNATIONAL JOURNAL OF FATIGUE
(2023)
Article
Engineering, Mechanical
Tao Shi, Jingyu Sun, Jianghua Li, Guian Qian, Youshi Hong
Summary: Using machine learning models and data interpolation, the influence of defect features on the fatigue performance of selective laser melted AlSi10Mg alloys was investigated. The results showed that increasing defect distance, circularity, and layer thickness improved fatigue life, while increasing stress amplitude, stress ratio, and defect size decreased fatigue life.
INTERNATIONAL JOURNAL OF FATIGUE
(2023)
Article
Engineering, Mechanical
Yujin Liu, Huang Yuan
Summary: In this paper, a hierarchical mechanism-informed neural network (HMNN) life prediction method was proposed. Fretting fatigue was addressed in four neural network layers, each focusing on a specific type of fatigue. The HMNN approach accurately predicts various kinds of fatigue and offers a new method for assessing complex fatigue.
INTERNATIONAL JOURNAL OF FATIGUE
(2023)
Article
Engineering, Mechanical
Cheng Luo, Huang Yuan
Summary: This study investigated the thermomechanical fatigue behavior of nickel-base single-crystal superalloy with different crystal orientations. The crack initiation modes and damage mechanisms were characterized using SEM and optical microscopy. In IP-TMF, creep damage originated from casting pores and propagated under mode I. The creep facets were influenced by activated slip systems, while fatigue damage depended on crystal orientation and developed by slipping along different crystallographic planes. In OP-TMF tests, oxidation-assisted cracking was non-crystallographic for all crystal orientations, with the crack growing within the oxidized material.
INTERNATIONAL JOURNAL OF FATIGUE
(2023)
Article
Materials Science, Multidisciplinary
Jingyu Sun, Guian Qian, Jianghua Li, Ruiyang Li, Zhimo Jian, Youshi Hong, Filippo Berto
Summary: Currently, there is no systematic approach to simulate the microstructure sensitive crack initiation and propagation process in very-high-cycle fatigue. In this study, a computational framework combining crystal plasticity and cohesive zone model is developed to simulate the defect-induced short crack growth in an additively manufactured AlSi10Mg alloy. The framework can control the crack growth rate and the proportion of crack initiation damage in the total damage. An acceleration strategy is proposed to improve the computational efficiency for very-high-cycle fatigue. Experimental observations and simulation results show good agreement.
JOURNAL OF THE MECHANICS AND PHYSICS OF SOLIDS
(2023)
Article
Mechanics
Meiling Xu, Huang Yuan
Summary: This study investigates the crack-tip stress fields of elastoplastic fatigue crack growth with crack closure and their correlation to the Delta J-integral. The computational results show that the singularity of the effective stress ranges during the opening process decreases with increasing crack closure, while the effective stress ranges during the closing process follow the HRR solution form. The farfield Delta J(eff)-integral is proposed to characterize the stress at the crack tip during the closing process, which is independent of the loading ratio and the path dependence of the Delta J-integral. The proposed estimation formula for the effective Delta J(eff)-integral is applicable to different loading ratios and plastic hardening materials based on extensive FEM computations. The in-plane constraint effects in fatigue crack growth can be quantified using the J - Q concept of elastoplastic fracture mechanics within the framework of Delta J(eff)-Q characterization.
ENGINEERING FRACTURE MECHANICS
(2023)
Article
Engineering, Mechanical
Jiaqi Lu, Huang Yuan
Summary: This study focuses on quantifying creep and oxidation effects to predict isothermal and thermomechanical fatigue life in a nickel-based superalloy. Creep damage was evaluated using the time-fraction method and the ductility-exhaustion method. A diffusion-dominated environmental damage parameter based on oxygen-assisted intergranular cracking mechanism was proposed and applied to thermomechanical fatigue life assessment. The results suggest that creep damage is negligible while environmental damage appears to be more dominant in this study. The proposed model provides a unified description for both isothermal and thermomechanical fatigue.
INTERNATIONAL JOURNAL OF FATIGUE
(2023)
Article
Engineering, Mechanical
Huanbo Weng, Huang Yuan
Summary: This study investigates the correlation between fabric tensor and anisotropic cyclic crystal plasticity of nickel-based single-crystal alloys using neural networks. Microstructural representative volume elements with different single crystal morphologies were generated, and their deformation behaviors were studied under different loading conditions. The results confirmed that the fabric tensor can describe the mechanical behavior and capture the history-dependent anisotropic cyclic hardening or softening behavior of the material.
INTERNATIONAL JOURNAL OF PLASTICITY
(2023)
Article
Materials Science, Multidisciplinary
Zhi-Qiang Tao, Guian Qian, Xiang Li, Jingyu Sun, Zi-Ling Zhang, Dao-Hang Li
Summary: This article proposes an innovative approach for determining the critical plane with weight-averaged largest fatigue damage, considering the failure modes of materials. Depending on the shear cracking behavior or tensile failure behavior of the material, an appropriate critical plane model is selected, and a multiaxial fatigue lifetime estimation methodology is established. Validation results using six materials demonstrate that the proposed methodology accurately estimates the orientation angles of failure planes and provides satisfactory fatigue lifetime estimations for both shear and tensile failure mode materials. Furthermore, the critical plane framework can be extended to stress-based fatigue criteria, and prediction results are in good agreement with experimental data for two additional materials.
JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T
(2023)
Article
Nanoscience & Nanotechnology
Jie Zhang, Xiaoyang Chen, MingJian Ding, Jiaqiang Chen, Ping Yu
Summary: This study enhances the compositional inhomogeneity of relaxor ferroelectric thin films to improve their dielectric temperature stability. The prepared films exhibit a relatively high dielectric constant and a very low variation ratio of dielectric constant over a wide temperature range.
SCRIPTA MATERIALIA
(2024)
Article
Nanoscience & Nanotechnology
Xiaoyu Chen, Ranran Zhang, Hao Zou, Ling Li, Qiancheng Zhu, Wenming Zhang
Summary: Polyaniline-manganese dioxide composites exhibit high conductivity, long discharge platform, and stable circulation, and the specific capacity is increased by providing additional H+ ions to participate in the reaction.
SCRIPTA MATERIALIA
(2024)
Article
Nanoscience & Nanotechnology
Xutao Huang, Yinping Chen, Jianjun Wang, Gang Lu, Wenxin Wang, Zan Yao, Sixin Zhao, Yujie Liu, Qian Li
Summary: This study aims to establish a novel approach to better understand and predict the behavior of materials with multi-scale lamellar microstructures. High-resolution reconstruction and collaborative characterization methods are used to accurately represent the microstructure. The mechanical properties of pearlite are investigated using crystal plasticity simulation and in-situ scanning electron microscopy tensile testing. The results validate the reliability of the novel strategy.
SCRIPTA MATERIALIA
(2024)
Article
Nanoscience & Nanotechnology
Cheng Chen, Fanchao Meng, Jun Song
Summary: This study systematically investigated the unfaulting mechanism of single-layer interstitial dislocation loops in irradiated L12-Ni3Al. The unfaulting routes of the loops were uncovered and the symmetry breaking during the unfaulting processes was further elucidated. A continuum model was formulated to analyze the energetics of the loops and predict the unfaulting threshold.
SCRIPTA MATERIALIA
(2024)
Article
Nanoscience & Nanotechnology
Darshan Bamney, Laurent Capolungo
Summary: This work investigates the formation of adjoining twin pairs (ATPs) at grain boundaries (GBs) in hexagonal close-packed (hcp) metals, focusing on the co-nucleation (CN) of pairs of deformation twins. A continuum defect mechanics model is proposed to study the energetic feasibility of CN of ATPs resulting from GB dislocation dissociation. The model reveals that CN is preferred over the nucleation of a single twin variant for low misorientation angle GBs. Further analysis considering GB character and twin system alignment suggests that CN events could be responsible for ATP formation even at low m' values.
SCRIPTA MATERIALIA
(2024)
Article
Nanoscience & Nanotechnology
Bing Han, Zhengqian Fu, Guoxiang Zhao, Xuefeng Chen, Genshui Wang, Fangfang Xu
Summary: This study investigates the behavior of electric-field induced antiferroelectric to ferroelectric (AFE-FE) phase transition and reveals the evolution of atomic displacement ordering as the cause for the transition behavior changing from sharp to diffuse. The novel semi-ordered configuration results from the competing interaction between long-range displacement modulation and compositional inhomogeneity, which leads to a diffuse AFE-FE transition while maintaining the switching field.
SCRIPTA MATERIALIA
(2024)
Article
Nanoscience & Nanotechnology
Akib Jabed, Golden Kumar
Summary: This study demonstrates that cryogenic rejuvenation promotes homogeneous-like flow and increases ductility in metallic glass samples. Conversely, annealing has the opposite effect, resulting in a smoother fracture surface.
SCRIPTA MATERIALIA
(2024)
Article
Nanoscience & Nanotechnology
Xin Ji, Yan Chong, Satoshi Emura, Koichi Tsuchiya
Summary: A heterogeneous microstructure in Ti-15Mo-3Al alloy with heterogeneous distributions of Mo element and omega(iso) precipitates has achieved a four-fold increase in tensile ductility without a loss of tensile strength, by blocking the propagation of dislocation channels and preventing the formation of micro-cracks.
SCRIPTA MATERIALIA
(2024)
Article
Nanoscience & Nanotechnology
Amit Samanta, Prasanna Balaprakash, Sylvie Aubry, Brian K. Lin
Summary: This study proposes a combined large-scale first principles approach with machine learning and materials informatics to quickly explore the chemistry-composition space of advanced high strength steels (AHSS). The distribution of aluminum and manganese atoms in iron is systematically explored using first principles calculations to investigate low stacking fault energy configurations. The use of an automated machine learning tool, DeepHyper, speeds up the computational process. The study provides insights into the distribution of aluminum and manganese atoms in systems containing stacking faults and their effects on the equilibrium distribution.
SCRIPTA MATERIALIA
(2024)
Article
Nanoscience & Nanotechnology
Guowei Zhou, Yuanzhe Hu, Zizheng Cao, Myoung Gyu Lee, Dayong Li
Summary: In this work, a physics-constrained neural network is used to predict grain-level responses in FCC material by incorporating crystal plasticity theory. The key feature, shear strain rate of slip system, is identified based on crystal plasticity and incorporated into the loss function as physical constitutive equations. The introduction of physics constraints accelerates the convergence of the neural network model and improves prediction accuracy, especially for small-scale datasets. Transfer learning is performed to capture complex in-plane deformation of crystals with any initial orientations, including cyclic loading and arbitrary non-monotonic loading.
SCRIPTA MATERIALIA
(2024)
Article
Nanoscience & Nanotechnology
Pengfei Yang, Qichang Li, Zhongying Wang, Yuxiao Gao, Wei Jin, Weiping Xiao, Lei Wang, Fusheng Liu, Zexing Wu
Summary: In this study, the HER performance of Ru-based catalysts is significantly improved through the dual-doping strategy. The obtained catalyst exhibits excellent performance in alkaline freshwater and alkaline seawater, and can be stably operated in a self-assembled overall water splitting electrolyzer.
SCRIPTA MATERIALIA
(2024)
Article
Nanoscience & Nanotechnology
Ilias Bikmukhametov, Garritt J. Tucker, Gregory B. Thompson
Summary: Depositing a Ni-1at. % P film can facilitate the formation of multiple quintuple twin junctions, resulting in a five-fold twin structure and a pentagonal pyramid surface topology. The ability to control material structures offers opportunities for creating novel surface topologies, which can be used as arrays of field emitters or textured surfaces.
SCRIPTA MATERIALIA
(2024)
Article
Nanoscience & Nanotechnology
Zening Yang, Weiwei Sun, Zhengyu Sun, Mutian Zhang, Jin Yu, Yubin Wen
Summary: Multicomponent oxides (MCOs) have wide applications and accurately predicting their thermal expansion remains challenging. This study introduces an innovative attention-based deep learning model, which achieves improved performance by using two self-attention modules and demonstrates adaptability and interpretability.
SCRIPTA MATERIALIA
(2024)
Article
Nanoscience & Nanotechnology
Ze Liu, Cai Chen, Yuanxun Zhou, Lanting Zhang, Hong Wang
Summary: This study attempts to address the gap in cooling rates between thin film deposition and bulk metallic glass (BMG) casting by correlating the glass-forming range (GFR) determined from combinatorial materials chips (CMCs) with the glass-forming ability (GFA) of BMG. The results show that the full-width at half maximum (FWHM) of the first sharp diffraction peak (FSDP) is a good indicator of BMG GFA, and strong positive correlations between FWHM and the critical casting diameter (Dmax) are observed in various BMG systems. Furthermore, the Pearson correlation coefficients suggest possible similarities in the GFA natures of certain BMG pairs.
SCRIPTA MATERIALIA
(2024)
Article
Nanoscience & Nanotechnology
Mike Schneider, Jean-Philippe Couzinie, Amin Shalabi, Farhad Ibrahimkhel, Alberto Ferrari, Fritz Koermann, Guillaume Laplanche
Summary: This work aims to predict the microstructure of recrystallized medium and high-entropy alloys, particularly the density and thickness of annealing twins. Through experiments and simulations, a database is provided for twin boundary engineering in alloy development. The results also support existing theories and empirical relationships.
SCRIPTA MATERIALIA
(2024)
