International Journal of Fatigue最新文献_第9页

The effects of stress ratio and temperature on fatigue behavior of an epoxy adhesive 应力比和温度对粘弹性环氧胶粘剂疲劳性能的影响

IF 6.8 2区材料科学 Q1 ENGINEERING, MECHANICAL

International Journal of Fatigue

Pub Date : 2025-11-22 DOI: 10.1016/j.ijfatigue.2025.109401

Lulu Liu , Thomas Keller , A.Vahid Movahedi-Rad

Epoxy adhesives are widely used in outdoor structural applications for bonding, where they are often subjected to cyclic loading patterns at different environmental temperatures, nevertheless, their synergistic effect on fatigue behavior has not yet been fully experimentally investigated. This study examined the tension–tension fatigue behavior of a structural epoxy at stress ratios (R) of 0.1, 0.5 and 0.9 and temperatures of 20 °C, 40 °C and 55 °C, where the onset glass transition temperature (T_g-onset) was 49 °C. At each temperature, increasing R extended fatigue life, particularly at 20 °C. This effect was slightly reduced at 40 °C, particularly at R = 0.9, because creep was accelerated at high temperature. At R = 0.5 and R = 0.9, fatigue life decreased with increasing temperature, while at R = 0.1, little change was observed when temperature increased from 20 °C to 40 °C. At 55 °C, exceeding T_g-onset, fatigue life significantly decreased across all stress ratios due to thermal softening. Stiffness degradation was predominantly attributed to damage initiation resulted from cyclic loading and thermal softening at elevated temperature, while creep effect was very limited, as observed at R = 0.9. The measured total energy dissipation for cyclic loading and creep exhibited that the contribution of creep increased with temperature. Finally, the constant life diagrams were formulated using a linear model by connecting the constant life points at R = 0.1 and R = 0.9, which showed good agreement at R = 0.5.

环氧胶粘剂广泛应用于室外结构粘接，在不同的环境温度下，环氧胶粘剂经常受到循环加载模式的影响，然而，它们对疲劳行为的协同效应尚未得到充分的实验研究。本研究测试了一种结构环氧树脂在应力比(R)为0.1、0.5和0.9，温度为20°C、40°C和55°C时的拉伸-拉伸疲劳行为，其中玻璃化转变起始温度（Tg-onset）为49°C。在每个温度下，R的增加都延长了疲劳寿命，特别是在20℃时。这种效应在40℃时略有减弱，特别是当R = 0.9时，因为蠕变在高温下加速。在R = 0.5和R = 0.9时，随着温度的升高，疲劳寿命降低，而在R = 0.1时，从20℃升高到40℃，疲劳寿命变化不大。在55°C，超过tg开始时，由于热软化，所有应力比的疲劳寿命都显著降低。在R = 0.9时，刚度退化主要是由循环加载和高温热软化引起的损伤引起的，而蠕变效应非常有限。循环加载和蠕变的总能量耗散表明，蠕变的贡献随温度的升高而增大。最后，通过连接R = 0.1和R = 0.9处的常数寿命点，采用线性模型绘制常数寿命图，在R = 0.5处一致性较好。

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引用次数: 0

Modeling of fatigue damage evolution and life prediction of aluminum adhesive joints subjected to hygrothermal aging 湿热老化下铝粘接疲劳损伤演化建模及寿命预测

IF 6.8 2区材料科学 Q1 ENGINEERING, MECHANICAL

International Journal of Fatigue

Pub Date : 2025-11-22 DOI: 10.1016/j.ijfatigue.2025.109403

Xiao Han , Congcong Zhang , Daxing Zhang , Ping Zhou

Adhesive bonding has progressively emerged as a primary joining method for advanced materials, driven by its high strength-to-weight ratio, uniform stress distribution, and ability to join dissimilar substrates. This renders the technique highly attractive to aerospace and automotive engineering. However, hygrothermal degradation remains a significant challenge limiting bonding reliability. In this study, single-lap adhesive joints were investigated. Hygrothermal aging and quasi-static tensile tests were first conducted. The results indicated that the ultimate tensile strength of the joints decreased by 25%, 48%, and 58% under one-third, two-thirds, and full moisture saturation, respectively, compared to the dry condition. Subsequently, fatigue tests at various load ratios were performed based on the initial findings, employing the back-strain technique for real-time monitoring. Following this, through secondary development of the finite-element platform, a hygrothermal-fatigue sequentially coupled fatigue-damage model based on the bilinear Cohesive Zone Model was established. In this model, an environmental degradation factor and a fatigue damage factor were introduced to characterize the coupled influence of aging and cyclic loading on the adhesive layer performance. The experimental results demonstrated that the hygrothermal environment significantly influences the fatigue life of the joints. The established sequentially coupled model proved capable of accurately predicting both fatigue life and crack propagation behavior, with an average simulation error of less than 5% compared to experimental data. These findings are expected to provide an important basis for the design and service-performance evaluation of adhesive structures.

由于其高强度重量比、均匀的应力分布以及连接不同基材的能力，粘合剂粘合已逐渐成为先进材料的主要连接方法。这使得该技术对航空航天和汽车工程具有很高的吸引力。然而，湿热降解仍然是限制粘接可靠性的重大挑战。在这项研究中，单搭胶接头进行了研究。首先进行了湿热老化和准静态拉伸试验。结果表明：三分之一、三分之二和全湿饱和状态下，节理的极限抗拉强度分别比干燥状态降低25%、48%和58%；随后，根据初步结果进行了不同载荷比下的疲劳试验，采用反应变技术进行实时监测。随后，通过对有限元平台的二次开发，建立了基于双线性黏聚区模型的湿热疲劳顺序耦合疲劳损伤模型。在该模型中，引入了环境退化因子和疲劳损伤因子来表征老化和循环载荷对粘接层性能的耦合影响。实验结果表明，湿热环境对接头的疲劳寿命有显著影响。所建立的序列耦合模型能够准确预测疲劳寿命和裂纹扩展行为，与实验数据相比，平均模拟误差小于5%。研究结果可为胶粘剂结构的设计和使用性能评价提供重要依据。

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引用次数: 0

Microstructure-related fatigue short crack growth behavior in LPBF TiC/Ti6Al4V: Grain deformation and predictive modeling LPBF TiC/Ti6Al4V合金微观组织相关疲劳短裂纹扩展行为：晶粒变形与预测建模

IF 6.8 2区材料科学 Q1 ENGINEERING, MECHANICAL

International Journal of Fatigue

Pub Date : 2025-11-22 DOI: 10.1016/j.ijfatigue.2025.109404

Asif Mahmood , Wei Li , Ibrahim Elbugdady , Muhammad Imran Lashari

This study employed in-situ fatigue testing to investigate the microstructural mechanisms governing fatigue short crack growth (FSCG) in laser powder bed fused TiC/Ti6Al4V titanium matrix composites under two stress ratios at room temperature. Advanced microscopic analyses were performed to reveal grain deformation along the crack path. Results indicate that FSCG occurred predominantly in a transgranular manner, showing pronounced effects of crystallographic orientation. Low-angle grain boundaries induced deflection, whereas high-angle grain boundaries effectively impeded short crack propagation. Furthermore, notch effects facilitated activation of multiple slip systems, and short cracks within grains tended to grow following prismatic and pyramidal slip planes. Moreover, the arrest of short cracks at grain boundaries was evaluated using a combination of microstructural and crystallographic parameters, including the geometrical compatibility factor, Schmid factor, and twist angle. These investigations along the crack path provide valuable insights into the microstructural factors that govern resistance to short crack growth, as well as clarify the pronounced fluctuations observed in the crack growth rate. Finally, building on this mechanistic understanding an analytical model for predicting the crack growth rate is proposed, showing good consistency with experimental results.

采用原位疲劳试验研究了室温下两种应力比下激光粉末床熔融TiC/Ti6Al4V钛基复合材料疲劳短裂纹扩展（FSCG）的组织机制。进行了先进的微观分析，以揭示沿裂纹路径的晶粒变形。结果表明，FSCG主要以穿晶方式发生，具有明显的晶体取向影响。低角度晶界诱发挠曲，而高角度晶界有效阻碍短裂纹扩展。此外，缺口效应促进了多重滑移系统的激活，晶粒内部的短裂纹倾向于沿棱柱形和锥体滑移面生长。此外，结合微观结构和晶体学参数，包括几何相容因子、施密德因子和扭转角，对晶界处短裂纹的止裂进行了评价。这些沿着裂纹路径进行的研究为研究控制短裂纹扩展阻力的微观结构因素提供了有价值的见解，并阐明了裂纹扩展速率中观察到的显著波动。最后，在此基础上提出了裂纹扩展速率预测的解析模型，该模型与实验结果具有较好的一致性。

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引用次数: 0

A high-accuracy exponential model for predicting the fatigue strength of metallic materials at different stress ratios 一种预测金属材料不同应力比下疲劳强度的高精度指数模型

IF 6.8 2区材料科学 Q1 ENGINEERING, MECHANICAL

International Journal of Fatigue

Pub Date : 2025-11-22 DOI: 10.1016/j.ijfatigue.2025.109400

Qiangsheng Wang , Xiaotao Li , Peng Zhang , Zhefeng Zhang

Fatigue strength is a critical parameter for evaluating the service safety of materials subjected to cyclic loading, and its dependence on the stress ratio (R) is essential in fatigue design of components. However, the existing stress ratio correction models frequently exhibit limited accuracy, narrow applicability across different R values, or heavy reliance on material-specific parameters. To overcome these limitations, we propose a high-accuracy exponential (HAE) model capable of predicting the fatigue strength of metallic materials at arbitrary stress ratios. The HAE model requires the fatigue strength data from only two reference stress ratios and employs an exponential function to accurately capture the nonlinear effect of R on fatigue performance. The validity and robustness of the HAE model were verified through analysis of 100 experimental data sets spanning the entire range of stress ratios for 16 kinds of different metallic materials. Comparative analysis with ten established correction models demonstrates that the HAE model consistently achieves superior predictive performance across all materials and stress ratios, with an average relative error of merely 5.08 % and a maximum error below 30 %. Due to its exceptional accuracy, minimal parameter requirements, and wide-ranging applicability, the HAE model serves as a reliable tool for the safety evaluation of engineering structures under complex service conditions, thus offering significant practical value in fatigue design.

疲劳强度是评价材料在循环载荷作用下使用安全性的重要参数，其与应力比(R)的关系在构件的疲劳设计中至关重要。然而，现有的应力比修正模型往往精度有限，在不同R值上的适用性较窄，或者严重依赖于材料特定参数。为了克服这些限制，我们提出了一种能够预测任意应力比下金属材料疲劳强度的高精度指数（HAE）模型。HAE模型只需要两个参考应力比的疲劳强度数据，并采用指数函数来准确捕捉R对疲劳性能的非线性影响。通过对16种不同金属材料的应力比范围内的100个实验数据集的分析，验证了HAE模型的有效性和鲁棒性。与10个已建立的修正模型的对比分析表明，HAE模型在所有材料和应力比下均具有优越的预测性能，平均相对误差仅为5.08%，最大误差低于30%。由于具有极高的精度、最小的参数要求和广泛的适用性，HAE模型是复杂使用条件下工程结构安全评估的可靠工具，因此在疲劳设计中具有重要的实用价值。

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引用次数: 0

Laboratory experiments on thermo-hydro-mechanical coupling fatigue characteristics of fissured sandstones 裂隙砂岩热-水-力耦合疲劳特性室内试验

IF 6.8 2区材料科学 Q1 ENGINEERING, MECHANICAL

International Journal of Fatigue

Pub Date : 2025-11-22 DOI: 10.1016/j.ijfatigue.2025.109415

Miaomiao Kou , Chenxi Li , Runke Dong

In this work, we investigate the fatigue mechanical responses and failure characteristics of white sandstone under thermo-hydro-mechanical (THM) coupling conditions through a series of laboratory experiments. In our triaxial fatigue tests, we consider the effects of high temperature, thermally induced damage, and cyclic hydraulic pressure, which contribute to a better understanding of the associated failure modes, global deformation behavior, strength degradation, and energy dissipation. Furthermore, the influences of confining pressure, pretreatment temperature, hydraulic pore fluid pressure, and fatigue parameters on THM coupling failure characteristics are systematically examined. A critical temperature zone affecting the fatigue failure process is identified based on macroscopic mechanical responses and failure patterns. To explore the underlying THM coupling mechanisms, we integrate microstructural observations with theoretical analysis, revealing the associated multiscale processes. Finally, we propose a new conceptual model to illustrate these complex THM coupling fatigue failure mechanisms.

在这项工作中，我们通过一系列的实验室实验，研究了热-水-力（THM）耦合条件下白色砂岩的疲劳力学响应和破坏特征。在我们的三轴疲劳试验中，我们考虑了高温、热致损伤和循环水力压力的影响，这有助于更好地理解相关的破坏模式、整体变形行为、强度退化和能量耗散。在此基础上，系统考察了围压、预处理温度、水力孔隙流体压力和疲劳参数对THM耦合破坏特性的影响。基于宏观力学响应和失效模式，确定了影响疲劳失效过程的临界温度区。为了探索潜在的THM耦合机制，我们将微观结构观察与理论分析相结合，揭示了相关的多尺度过程。最后，我们提出了一个新的概念模型来解释这些复杂的THM耦合疲劳失效机制。

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引用次数: 0

The role of rafting in small fatigue crack behaviours of a Ni-based single crystal superalloy at room temperature 漂流对ni基单晶高温合金室温小疲劳裂纹行为的影响

IF 6.8 2区材料科学 Q1 ENGINEERING, MECHANICAL

International Journal of Fatigue

Pub Date : 2025-11-22 DOI: 10.1016/j.ijfatigue.2025.109413

Y.S. Fan , T. Ren , C.L. Dong , X.G. Yang , D.Q. Shi

Small fatigue crack propagation tests are conducted along the [001] and [011] orientations in virgin and pre-rafting Ni-based single-crystal superalloys at room temperature. The results indicate that microstructural rafting substantially accelerates the crack propagation rate along the [001] orientation at room temperature whereas weak influence on the crack propagation rate along the [011] orientation. Transitions in crack path are observed for both virgin and rafting states along the [001] orientation. However, the crack in the rafting state undergoes a rapid transition from the initial shearing propagation mode to a nearly opening propagation mode, which is fundamentally contrary to the initial condition. Finally, a small fatigue crack propagation rate model considering the microstructural rafting state is established based on the crack-dislocation distribution theory and the microstructural strengthening mechanisms for Ni-based single crystal superalloy. The predicted results of the model showed good consistency with the experimental results.

在室温下，沿[001]和[011]取向对镍基单晶高温合金进行了疲劳裂纹扩展试验。结果表明：室温下，显微组织漂流对裂纹沿[001]取向的扩展速率有显著的促进作用，而对沿[011]取向的扩展速率影响较小；沿[001]取向观察到原始状态和漂流状态裂纹路径的转变。然而，在漂流状态下，裂纹从初始剪切扩展模式迅速转变为近张开扩展模式，这与初始条件根本相反。最后，基于裂纹-位错分布理论和ni基单晶高温合金的显微组织强化机理，建立了考虑微观组织流变状态的小疲劳裂纹扩展速率模型。模型的预测结果与实验结果吻合较好。

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引用次数: 0

3D microstructural damage quantification and comparative analysis of initiation mechanisms in woven and chopped composites under compressive fatigue 压缩疲劳下织切复合材料三维微结构损伤量化及起裂机理对比分析

IF 6.8 2区材料科学 Q1 ENGINEERING, MECHANICAL

International Journal of Fatigue

Pub Date : 2025-11-22 DOI: 10.1016/j.ijfatigue.2025.109398

Mritunjay M. Hiremath , Timo Bernthaler , Pascal Anger , Sushil K. Mishra , Anirban Guha , Asim Tewari

Fibre reinforced polymer (FRP) composites such as woven roving mat (WRM) and chopped strand mat (CSM) are widely used in structural applications but remain susceptible to irreversible damage under cyclic vibrations and pulsating forces. The compressive fatigue behaviour of such composites has received relatively limited attention. In this study, the compression-compression (C–C) and tension–compression (T–C) fatigue responses of WRM and CSM composites were experimentally investigated through cyclic loading tests combined with stereological quantification of microstructural damage. Scanning electron microscopy was employed to characterize crack morphology, while finite element simulations were conducted to interpret the mechanisms governing crack initiation. The stiffness degradation in WRM composites was approximately 22.5 % under T–C and 0.3 % under C–C fatigue loading after 100,000 cycles, whereas CSM composites showed 8.8 % degradation under T–C with negligible change under C–C fatigue. In CSM, fatigue cracks were predominantly oriented parallel to the loading direction, with stereological analyses revealing a 9.5 % higher number density of such cracks under C–C (3.49

\times

10⁻⁴

μ m^{- 2}

) compared to T–C (3.19

\times

10⁻⁴

μ m^{- 2}

) cyclic loading. In contrast, WRM primarily exhibited inter-yarn debonding and matrix-dominated cracking. Finite element analyses confirmed that fibre clustering in CSM induces local shear stresses that promote parallel crack formation, while the woven architecture of WRM restricts such crack development. These findings provide a mechanistic understanding of damage initiation under compressive fatigue and offer guidance for improving the fatigue durability of FRP composites through microstructural design.

纤维增强聚合物（FRP）复合材料，如编织粗纱毡（WRM）和短切条毡（CSM）在结构应用中得到了广泛的应用，但在循环振动和脉动力作用下容易产生不可逆损伤。这种复合材料的压缩疲劳性能得到了相对有限的关注。本研究通过循环加载试验结合细观损伤的立体学量化，对WRM和CSM复合材料的压缩-压缩（C-C）和拉-压缩（T-C）疲劳响应进行了实验研究。扫描电镜对裂纹形貌进行了表征，有限元模拟对裂纹起裂机理进行了解释。10万次循环后，WRM复合材料在T-C和C-C疲劳载荷下的刚度退化约为22.5%和0.3%，而CSM复合材料在T-C疲劳载荷下的刚度退化为8.8%，C-C疲劳载荷下的变化可以忽略不计。在CSM中，疲劳裂纹主要平行于加载方向，体力学分析表明，C-C （3.49 × 10−4 μm-2）循环加载下的疲劳裂纹数密度比T-C （3.19 × 10−4 μm-2）循环加载下的疲劳裂纹数密度高9.5%。相反，WRM主要表现为纱线间脱粘和基体主导的开裂。有限元分析证实，纤维在CSM中的聚集会产生局部剪应力，促进平行裂纹的形成，而WRM的编织结构则限制了这种裂纹的发展。这些研究结果为进一步理解压缩疲劳下的损伤起裂机理提供了理论依据，并为通过微结构设计提高FRP复合材料的疲劳耐久性提供了指导。

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引用次数: 0

Fatigue life estimation of a UD CFRP composite ply under transverse tensile load – An experimental & computational micromechanical RVE approach 横向拉伸载荷下UD CFRP复合材料层的疲劳寿命估算——一种实验与计算微机械RVE方法

IF 6.8 2区材料科学 Q1 ENGINEERING, MECHANICAL

International Journal of Fatigue

Pub Date : 2025-11-21 DOI: 10.1016/j.ijfatigue.2025.109394

B.A. Wani , S. Daggumati , Y. Akkala , C. Ramadas

The current research work presents a computational micromechanics-based Finite Element (FE) framework to predict the fatigue damage behavior and corresponding life (S-N curve) of a unidirectional (UD) Carbon Fiber Reinforced Polymer (CFRP) composite ply under transverse tension–tension fatigue loads. A Representative Volume Element (RVE) model incorporating fibers, matrix, and fiber/matrix interface is developed. To accurately capture the mechanical behavior of the matrix in the RVE model, neat epoxy specimens were tested under quasi-static and fatigue loading. Subsequent fractographic analysis revealed that a nonlinear elastic material model, combined with a pressure-dependent modified von Mises criterion, effectively captures the epoxy matrix static and fatigue failure behavior. Fiber/matrix interface failure in the High-Cycle Fatigue (HCF) region is simulated using a two-step approach: (1) damage initiation in interfacial cohesive elements under low load severities is triggered by a phenomenological model based on the experimental transverse ply damage initiation S-N curve, and (2) subsequent crack growth is governed by a cohesive zone model integrated with a fracture mechanics-based Paris law formulations. The proposed RVE modeling framework is thoroughly validated against experimental results under both quasi-static and fatigue loading. A detailed computational and experimental analysis led to the following key observations: (i) neat epoxy matrix exhibits brittle failure at different load severities in the HCF region; (ii) under the applied transverse tension–tension fatigue load (R = 0.1), ply-level failure initiates as fiber/matrix interface debonding, followed by matrix cracking; and (iii) the mode I Paris law parameter (

m_{I}

) of the fiber/matrix interface has a significant influence on the predicted transverse fatigue life of a UD composite ply.

本研究提出了一种基于计算微力学的有限元框架，用于预测单向碳纤维增强聚合物（CFRP）复合材料层在横向拉伸疲劳载荷下的疲劳损伤行为和相应的寿命（S-N曲线）。建立了包含纤维、基体和纤维/基体界面的代表性体积元（RVE）模型。为了准确捕捉RVE模型中基体的力学行为，对纯环氧树脂试件进行了准静态和疲劳加载试验。随后的断口分析表明，非线性弹性材料模型与压力相关的改进von Mises准则相结合，有效地捕获了环氧基的静态和疲劳破坏行为。采用两步方法对高周疲劳区纤维/基体界面破坏进行了模拟：(1)低载荷强度下界面黏结单元的损伤起裂是由基于实验横铺损伤起裂S-N曲线的现象学模型触发的；(2)随后的裂纹扩展是由基于断裂力学的Paris定律公式的黏结区模型控制的。本文提出的RVE模型框架在准静态和疲劳载荷下均得到了实验验证。通过详细的计算和实验分析，得出以下重要结论：(1)纯环氧基在不同荷载强度下在HCF区域呈现脆性破坏；（ii）在施加横向拉伸-拉伸疲劳载荷（R = 0.1）的情况下，纤维/基体界面首先发生脱粘，而后发生基体开裂；(3)纤维/基体界面的I型巴黎定律参数（mI）对UD复合材料层的横向疲劳寿命预测有显著影响。

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引用次数: 0

Primary creep regeneration evolution of nuclear grade 316H stainless steel under cyclic creep loading: experiments and non-unified constitutive model 循环蠕变加载下核级316H不锈钢初蠕变再生演化：实验与非统一本构模型

IF 6.8 2区材料科学 Q1 ENGINEERING, MECHANICAL

International Journal of Fatigue

Pub Date : 2025-11-20 DOI: 10.1016/j.ijfatigue.2025.109395

Cheng Gong , Qian Niu , Li Sun , Xiaotao Zheng , Haofeng Chen

In Generation IV nuclear power systems, cyclic creep responses represent a critical factor governing both the lifetime design and operational safety of high-temperature components. Under such loading conditions, the imposition of reverse loading followed by reloading frequently triggers an acceleration of creep rate, commonly referred to as primary creep regeneration (PCR). This phenomenon exacerbates time-dependent deformation and markedly expedites the onset of material failure. Accordingly, in this study, a series of tests were conducted on nuclear grade 316H stainless steel at 650 °C to investigate the evolution and governing mechanism of PCR behavior during cyclic creep. The results reveal that lower forward loading and higher reverse loading promotes greater relative reverse plastic deformation, thereby enhancing the overall PCR behavior. The reduction in reverse plastic deformation in each cycle driven by cyclic hardening attenuates the PCR behavior over successive cyclic creep loading. Based on these findings, a plasticity-creep superposition model was developed by integrating the Ohno-Abdel-Karim kinematic hardening framework with a modified Gorash’s creep model that accounts for PCR behavior. The proposed model effectively captures the evolution of PCR behavior and the stress–strain response during cyclic creep loading. This study not only comprehensively elucidates the impact of cyclic deformation on the evolution of PCR behavior, but also provides a robust modelling framework for the precise prediction of high-temperature material deformation, thereby contributing to the structural integrity assessment of Generation IV nuclear power systems.

在第四代核电系统中，循环蠕变响应是控制高温部件寿命设计和运行安全的关键因素。在这样的加载条件下，施加反向加载后再加载通常会触发蠕变速率的加速，通常被称为初始蠕变再生（PCR）。这种现象加剧了随时间的变形，并明显加速了材料失效的发生。因此，本研究对核级316H不锈钢在650℃下进行了一系列试验，以研究循环蠕变过程中PCR行为的演变及其调控机制。结果表明，较低的正向加载和较高的反向加载促进了较大的相对反向塑性变形，从而增强了整体PCR行为。由循环硬化驱动的每个循环中反向塑性变形的减少减弱了连续循环蠕变加载的PCR行为。基于这些发现，通过将Ohno-Abdel-Karim运动学硬化框架与解释PCR行为的改进Gorash蠕变模型相结合，建立了塑性-蠕变叠加模型。该模型有效地捕捉了循环蠕变加载过程中PCR行为和应力-应变响应的演变过程。本研究不仅全面阐明了循环变形对PCR行为演变的影响，而且为高温材料变形的精确预测提供了稳健的建模框架，从而有助于第四代核电系统的结构完整性评估。

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引用次数: 0

Investigation on the effect of machined surface texture on surface integrity and torsional fatigue behavior of ultra-high strength steel treated by ultrasonic surface rolling process 加工表面织构对超声表面轧制超高强度钢表面完整性和扭转疲劳性能影响的研究

IF 6.8 2区材料科学 Q1 ENGINEERING, MECHANICAL

International Journal of Fatigue

Pub Date : 2025-11-20 DOI: 10.1016/j.ijfatigue.2025.109396

Zhicheng Dai , Kai Du , Pei Yan , Jiabin Liang , Siyu Li , Xibin Wang

This investigation conducted ultrasonic surface rolling processing (USRP) and torsional fatigue testing on 45CrNiMoVA ultra-high-strength steel with various hard turning (HT) surface textures. It investigated the influence of HT-machined surface topography on USRP-induced surface integrity and torsional fatigue behavior. An energy-based predictive model incorporating machined surface integrity was established for torsional fatigue life assessment. The results showed that post-USRP surface roughness consistently fell within the range of 0.4–0.8 μm across HT-processed surfaces with varying scallop heights. Surfaces featuring HT textures enabled USRP to achieve a maximum plastic deformation layer depth of 95 μm, with an average grain size refined to 0.52 μm. Distinct HT surface topographies significantly altered torsional fatigue life under USRP treatment. HT surfaces featuring a tool nose radius of 0.2 mm and scallop height of 60 μm achieved exceptional post-USRP torsional fatigue life exceeding 60,000 cycles. Fracture mode variations impacted the torsional fatigue life. Hybrid fracture modes involving combined normal stress, transverse shear stress, and longitudinal shear stress reduced crack propagation rates and enhanced torsional fatigue performance. Under torsional loading, 45CrNiMoVA exhibited cyclic softening behavior in its shear stress response. The torsional fatigue life prediction model considering surface integrity demonstrated minimum and mean prediction accuracies of 84.9 % and 93.7 %, surpassing the predictive capability of conventional energy-based models. This investigation provides critical insights into how machined surface textures influence post-enhanced surface integrity and torsional fatigue behavior, and demonstrates that the surface performance of components can also be improved through the rough machining-strengthening process without the finish machining.

对45CrNiMoVA超高强度钢不同硬车削（HT）表面织构进行了超声表面轧制加工（USRP）和扭转疲劳试验。研究了高温加工表面形貌对usrp诱导表面完整性和扭转疲劳性能的影响。建立了考虑加工表面完整性的基于能量的扭转疲劳寿命预测模型。结果表明，在不同扇贝高度的高温处理表面，usrp后表面粗糙度始终在0.4-0.8 μm范围内。具有HT纹理的表面使USRP实现了95 μm的最大塑性变形层深度，平均晶粒尺寸细化到0.52 μm。不同的高温表面形貌显著改变了USRP处理下的扭转疲劳寿命。HT表面具有0.2 mm的刀头半径和60 μm的扇贝高度，在usrp后获得了超过60,000次的扭转疲劳寿命。断裂模式的变化影响扭转疲劳寿命。包括正应力、横向剪应力和纵向剪应力的混合断裂模式降低了裂纹扩展速率，提高了扭转疲劳性能。在扭转荷载作用下，45CrNiMoVA的剪应力响应表现出循环软化行为。考虑表面完整性的扭转疲劳寿命预测模型的最小预测精度为84.9%，平均预测精度为93.7%，超过了传统的基于能量的模型的预测能力。该研究为加工后的表面纹理如何影响增强后的表面完整性和扭转疲劳行为提供了重要的见解，并证明了部件的表面性能也可以通过粗加工强化过程得到改善，而无需精加工。

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