An investigation was conducted on the low cycle fatigue behavior, fatigue life, and fatigue fracture mechanism of forged 316LN stainless steel at 330°C, under varying strain amplitudes. The results indicate that ...
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An investigation was conducted on the low cycle fatigue behavior, fatigue life, and fatigue fracture mechanism of forged 316LN stainless steel at 330°C, under varying strain amplitudes. The results indicate that the cyclic softening degree of 316LN austenitic stainless steel increases proportionally with the strain amplitude. This increase can be attributed to variations in the arrangement and development process of the dislocation ***, it was observed that both back stress and friction stress augment as the total strain amplitude increases. This phenomenon is primarily caused by enhanced interactions between dislocations and precipitated phases, as well as dislocations themselves. The hysteresis loop area exhibits an increase in direct correlation with the total strain amplitude. Moreover, a smaller strain amplitude corresponds to reduced plastic strain energy and increased fatigue life. In engineering applications, the simplicity and universality of a model, along with easily obtainable parameters, are crucial considerations. To evaluate the fatigue life of 316LN austenitic stainless steel,four models were employed: Coffin-Manson fatigue life model, energy life model, three-parameter power model,and three-parameter power life correction model. The predicted data from the three-parameter power life correction model fell within the acceptable error range of 1.2, demonstrating a strong alignment with the experimental values. Consequently, it can be concluded that the three-parameter power life correction model exhibits remarkable accuracy in predicting low cycle fatigue(LCF) behavior, thereby facilitating the safety assessment of component lifespan. The fatigue fracture surface exhibits distinct features of fatigue striations, with a noticeable decrease in the interval between these striations as the total strain amplitude increases.
Boron arsenide(BAs)is a promising integrated circuit thermal management material with ultra-high thermal conductivity(κ)and exceptional semiconductor *** practical devices,mechanical stress and strain caused by therm...
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Boron arsenide(BAs)is a promising integrated circuit thermal management material with ultra-high thermal conductivity(κ)and exceptional semiconductor *** practical devices,mechanical stress and strain caused by thermal expansion inevitably affect the thermodynamic properties of heat sink ***,investigation of the effects of stress and strain on theκof BAs is *** assessment and regulation of theκand phonon heat transport of BAs requires consideration of both three-phonon(3ph)and four-phonon(4ph)***,anharmonicity computation using density functional theory is computationally expensive,particularly for the fourth-order interatomic force *** work uses a machine learning-driven moment tensor potential method to evaluate higher-order anharmonicity and extends it to include fourth-order forces,accelerating the calculations *** show that theκof BAs calculated using the moment tensor potential method when considering both 3ph and 4ph processes agrees well with experimental *** contrast,considering the 3ph interaction alone causesκto be *** machine learning approach reduces computational costs by approximately 94%while maintaining comparable accuracy to density functional *** solving the phonon Boltzmann transport equation,the thermal transport properties of BAs under biaxial tensile strains ranging up to 7%are *** shows an anomalousκenhancement when including both 3ph and 4ph interactions,with a maximum enhancement of 15%at a small strain of 1%,primarily because of the weakening of the 3ph *** 2%strain,both the 3ph and 4ph scattering rates increase significantly,causing shorter phonon lifetimes and a monotonic reduction inκ.Additionally,theκtemperature dependence under strain is explored,highlighting temperature’s role in modulating phonon *** study provides machine learning-driven insights into the BAs thermal response under bi
Research on the expansion and fracture of explosively driven metal shells has been a key issue in weapon development and structural *** is important to study and predict the failure mode,fracture mechanism,and fragmen...
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Research on the expansion and fracture of explosively driven metal shells has been a key issue in weapon development and structural *** is important to study and predict the failure mode,fracture mechanism,and fragment distribution characteristics of explosively driven metal *** this study,we used the finite element-smoothed particle hydrodynamics(FE-SPH)adaptive method and the fluid-structure interaction method to perform a three-dimensional numerical simulation of the expansion and fracture of a metal cylindrical *** method combined the advantages of the FEM and SPH,avoiding system mass loss,energy loss,and element distortion;in addition,the proposed method had a good simulation effect on the interaction between detonation waves and the cylindrical *** simulated detonation wave propagation,shell damage morphology,and fragment velocity distribution were in good agreement with theoretical and experimental *** divided the fragments into three regions based on their shape *** analyzed the failure mode and formation process of fragments in different *** numerical results reproduced the phenomenon in which cracks initiated from the inner surface and extended to the outer surface of the cylindrical shell along the 45°or 135°shear *** addition,fragments composed of elements are identified,and the mass and characteristic lengths of typical fragments at a stable time are ***,the mass and size distribution characteristics of the fragments were explored,and the variation in the fitting results of the classical distribution function under different explosion pressures was ***,based on mathematical derivation,the distribution formula of fragment velocity was *** improved formula provided higher accuracy and could be used to analyze any metal cylindrical shells with different length-to-diameter ratios.
Achiral dielectric nanostructures provide an efficient method for discriminating left-and right-circularly polarized photons,leveraging the photothermoelectric effect.
Achiral dielectric nanostructures provide an efficient method for discriminating left-and right-circularly polarized photons,leveraging the photothermoelectric effect.
One of the challenges in material design is to rapidly develop new materials or improve the performance of materials by utilizing the data and knowledge of existing ***,a rapid and effective method of alloy material d...
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One of the challenges in material design is to rapidly develop new materials or improve the performance of materials by utilizing the data and knowledge of existing ***,a rapid and effective method of alloy material design via data transfer learning is proposed to efficiently design new alloys using existing data.A new type of aluminum alloy(E2 alloy)with ultra strength and high toughness previously developed by the authors is used as an *** optimal three-stage solution-aging treatment process(T66R)was efficiently designed transferring 1053 pieces of process-property relationship data of existing AA7xxx commercial aluminum *** realizes the substantial improvement of strength and plasticity of E2 alloy simultaneously,which is of great significance for lightweight of high-end ***,the microstructure analysis clarifies the mechanism of alloy performance *** study shows that transferring the existing alloy data is an effective method to design new alloys.
With the rapid development of the internet in the past decade, it has become increasingly important to extract valuable information from vast resources efficiently, which is crucial for establishing a comprehensive di...
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With the rapid development of the internet in the past decade, it has become increasingly important to extract valuable information from vast resources efficiently, which is crucial for establishing a comprehensive digital ecosystem, particularly in the context of research surveys and comprehension. The foundation of these tasks focuses on accurate extraction and deep mining of data from scientific documents, which are essential for building a robust data infrastructure. However, parsing raw data or extracting data from complex scientific documents have been ongoing challenges. Current data extraction methods for scientific documents typically use rule-based (RB) or machine learning (ML) approaches. However, using rule-based methods can incur high coding costs for articles with intricate typesetting. Conversely, relying solely on machine learning methods necessitates annotation work for complex content types within the scientific document, which can be costly. Additionally, few studies have thoroughly defined and explored the hierarchical layout within scientific documents. The lack of a comprehensive definition of the internal structure and elements of the documents indirectly impacts the accuracy of text classification and object recognition tasks. From the perspective of analyzing the standard layout and typesetting used in the specified publication, we propose a new document layout analysis framework called Compartment and Text Blocks Refinement (CTBR). Firstly, we define scientific documents into hierarchical divisions: base domain, compartment, and text blocks. Next, we conduct an in-depth exploration and classification of the meanings of text blocks. Finally, we utilize the results of text block classification to implement object recognition within scientific documents based on rule-based compartment segmentation. For the experiment, we used the well-known ACL format proceeding articles as experimental data for the validation experiment. The experiment shows
Owing to its unique two-dimensional structure and tunable electronic properties,MoS_(2)has emerged as a promising electromagnetic wave(EMW)-absorbing material that can be extensively combined with various other substa...
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Owing to its unique two-dimensional structure and tunable electronic properties,MoS_(2)has emerged as a promising electromagnetic wave(EMW)-absorbing material that can be extensively combined with various other substances to construct effective EMW ***,research on cation substitution doping in MoS_(2)remains relatively limited,which impedes the design and development of high-performance MoS_(2)-based EMW absorbing *** this study,MoS_(2)was synthesized with various concentrations of doped Fe via a facile hydrothermal *** thoroughly investigated the effects of Fe doping,which induced lattice distortion and collapse,triggered a 1T‒2H phase transition,and led to the formation and evolution of second *** modulation of phase transitions,coupled with doping-induced lattice defects that enhance polarization and interfacial polarization from second phases,enabled the Fe-doped MoS_(2)samples to exhibit remarkable EMW absorption ***,the sample FM3 achieved an effective absorption bandwidth(EAB)of 5.1 GHz and a minimum reflection loss(RLmin)of−60.6 dB,underscoring the critical role of Fe doping in increasing the EMW absorption *** research provides valuable pathways and unique insights for the advancement of transition metal dichalcogenides(TMDs)as high-performance EMW-absorbing materials.
High-throughput materials research is strongly required to accelerate the development of safe and high energy-density lithium-ion battery(LIB)applicable to electric vehicle and energy storage *** artificial intelligen...
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High-throughput materials research is strongly required to accelerate the development of safe and high energy-density lithium-ion battery(LIB)applicable to electric vehicle and energy storage *** artificial intelligence,including machine learning with neural networks such as Boltzmann neural networks and convolutional neural networks(CNN),is a powerful tool to explore next-generation electrode materials and functional additives.
Oxygenated carbon materials exhibit outstanding electrocatalytic performance in the production of hydrogen peroxide(H2O2)through a two-electron oxygen reduction *** nature of the active functional group and underlying...
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Oxygenated carbon materials exhibit outstanding electrocatalytic performance in the production of hydrogen peroxide(H2O2)through a two-electron oxygen reduction *** nature of the active functional group and underlying reaction mechanism,however,remain ***,a comprehensive workflow was established to identify the active sites from the numerous possible *** common hydroxyl group at the notched edge demonstrates a key role in the two-electron *** local chemical environment weakens the binding of OOH intermediate to substrate while enhancing interaction with solution,thereby promoting the H_(2)O_(2)*** increasing pH,the intramolecular hydrogen bond between OOH intermediate and hydroxyl decreases,facilitating OOH ***,the rise in selectivity with increasing potential stems from the suppression of the four-electron *** active site was further validated through *** by theoretical understanding,optimal performance was achieved with high selectivity(>95%)and current density(2.06 mA/cm^(2))in experiment.
Laser powder bed fusion (LPBF) is a commonly used additive manufacturing (AM) method for efficiently producing intricate geometric components. This investigation examines factors such as pores, cellular structure, gra...
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Laser powder bed fusion (LPBF) is a commonly used additive manufacturing (AM) method for efficiently producing intricate geometric components. This investigation examines factors such as pores, cellular structure, grain size, and inclusions from the manufacturing process that contribute to the corrosion resistance of LPBF DSS. Furthermore, the as-built LPBF duplex stainless steel (DSS) is primarily ferrite due to the rapid cooling process. Therefore, the transformation of ferrite to austenite after various heat treatments in LPBF DSS and its corresponding corrosion resistance are presented. Additionally, a new mixed powder method is proposed to increase the austenite content in the as-built LPBF DSS. This review also focuses on the passivation capability and pitting corrosion performance in LPBF and conventional DSS. This article summarizes the variations in microstructure between as-built and heat-treated LPBF DSS, with their impacts on corrosion resistance, offering insights for manufacturing highly corrosion-resistant LPBF DSS.
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