International Journal of Fatigue最新文献_第6页

Integrated detection for open and closed surface fatigue cracks utilizing scanning laser source-induced Rayleigh wave fields with self-reference peak-to-peak features 利用具有自参照峰-峰特征的扫描激光源诱导瑞利波场，综合检测开裂和闭合表面疲劳裂纹

IF 5.7 2区材料科学 Q1 ENGINEERING, MECHANICAL

International Journal of Fatigue

Pub Date : 2024-10-13 DOI: 10.1016/j.ijfatigue.2024.108649

Qichao Cheng , Jun He , Shixi Yang , Zixuan Guo , Xin Xiong

In this study, the integrated detection method for open and closed surface fatigue cracks is investigated. Firstly, the finite element simulation models are established to investigate the interaction between scanning laser source-induced Rayleigh waves and open and closed surface fatigue cracks, and the laser ultrasonic detection experiments are conducted for fatigue specimens containing fatigue cracks in different states. The simulation and experimental results indicate that the variation patterns in the peak-to-peak values of Rayleigh waves with horizontal scanning positions for open and closed cracks exhibit both similarities and differences. Subsequently, an integrated detection method based on self-referenced peak-to-peak features is proposed, which utilizes the similarities and differences to detect and distinguish open and closed cracks, respectively. Furthermore, this proposed method is experimentally validated, indicating that it can achieve accurate integrated imaging of open and closed cracks that have a high degree of agreement with the SEM images of the cracks. Additionally, the proposed method achieves a detection error of 2 % for the vertical lengths of the fatigue cracks. This study can provide guidance for integrated real-time detection of open and closed surface fatigue cracks of mechanical components in service.

本研究探讨了开闭合表面疲劳裂纹的综合检测方法。首先，建立了有限元仿真模型来研究扫描激光源诱导的瑞利波与开闭合表面疲劳裂纹之间的相互作用，并对含有不同状态疲劳裂纹的疲劳试样进行了激光超声检测实验。模拟和实验结果表明，开裂和闭合裂纹的瑞利波峰峰值随水平扫描位置的变化规律既有相似之处，也有不同之处。随后，提出了一种基于自参照峰峰值特征的综合检测方法，利用相似性和差异性分别检测和区分开裂和闭合裂纹。此外，实验还验证了所提出的方法，表明该方法可以实现开裂和闭合裂纹的精确综合成像，并与裂纹的扫描电镜图像高度一致。此外，该方法对疲劳裂纹垂直长度的检测误差仅为 2%。这项研究可为实时综合检测服役中机械部件的开裂和闭合表面疲劳裂纹提供指导。

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引用次数: 0

Vibration fatigue behavior and failure mechanism of Ni-based single-crystal film cooling hole structure under high temperature 高温下 Ni 基单晶膜冷却孔结构的振动疲劳行为和失效机理

IF 5.7 2区材料科学 Q1 ENGINEERING, MECHANICAL

International Journal of Fatigue

Pub Date : 2024-10-12 DOI: 10.1016/j.ijfatigue.2024.108646

Yujie Zhao, Yixin Qu, Weizhu Yang, Jiawei Wu, Lei Li

Film cooling hole structures significantly influence vibration fatigue performance of Ni-based single crystal turbine blades. This study investigates the vibration fatigue behavior and failure mechanism of film cooling hole structure of Ni-based single crystal superalloy at high temperature by using the plate specimens with film cooling holes. The vibration fatigue cracks are all initiated at the edge of the film cooling hole on specimen surface, and the macroscopic crack path is a straight line path. At the microscopic scale, the crack path at 850 °C is a Zigzag path, but the crack path at 980 °C still shows a straight line path. The crack initiation of the specimen shows the oxidation crack nucleation in the stress concentration area under the coupling effect of high temperature and alternating stress. The macroscopic crack propagation direction at high temperature depends on the stress gradient direction of the resolved shear stress. At the microscopic scale, the crack propagation at 850 °C is the dislocation slip-climb mechanism, and the crack propagation at 980 °C more inclined to produce only the dislocation climb mechanism. The vibration fatigue cracks have the temperature dependence. The high temperature environment promotes the activation of slip system and the enhancement of dislocation mobility, the microscopic raft structure promotes the crack propagation along the γ phase with a large number of dislocations, the oxidation crack promotes the oxygen to enter the alloy matrix, which accelerates the Mode-I crack propagation.

膜冷孔结构对 Ni 基单晶涡轮叶片的振动疲劳性能有很大影响。本研究利用带薄膜冷却孔的板材试样，研究了高温下镍基单晶超合金薄膜冷却孔结构的振动疲劳行为和失效机理。振动疲劳裂纹均起源于试样表面薄膜冷却孔的边缘，宏观裂纹路径为直线路径。在微观尺度上，850 ℃ 时的裂纹路径为之字形路径，但 980 ℃ 时的裂纹路径仍为直线路径。试样的裂纹起始显示了在高温和交变应力的耦合作用下，氧化裂纹在应力集中区域成核。高温下的宏观裂纹扩展方向取决于解析剪应力的应力梯度方向。在微观尺度上，850 ℃时的裂纹扩展是位错滑移爬升机制，而 980 ℃时的裂纹扩展更倾向于只产生位错爬升机制。振动疲劳裂纹具有温度依赖性。高温环境促进了滑移系统的活化和位错迁移率的提高，微观筏状结构促进了裂纹沿具有大量位错的γ相扩展，氧化裂纹促进了氧进入合金基体，从而加速了模式-I裂纹的扩展。

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引用次数: 0

Fatigue life modeling for a low alloy steel after long-term thermal aging 低合金钢长期热老化后的疲劳寿命建模

IF 5.7 2区材料科学 Q1 ENGINEERING, MECHANICAL

International Journal of Fatigue

Pub Date : 2024-10-11 DOI: 10.1016/j.ijfatigue.2024.108645

Long Jin , Ming-Liang Zhu , Shang-Lin Zhang , Min Yang , Tian-Da Yu , Fu-Zhen Xuan

Fatigue failure of materials has a considerable impact on the safety of equipment in service. In this study, axially tensile and low cycle fatigue tests were conducted on a low alloy steel after accelerated thermal aged at 450 °C for 10,000 h. The experimental results indicate that the ultimate and yield strengths increase moderately, while the fatigue life of specimens experience a slight decrease in this circumstance. The fracture analysis demonstrates that the bainite breaking facilitates the fatigue crack initiation and propagation after thermal aging, which is accompanied by a decrease in plastic strain amplitude. Therefore, the plastic strain amplitude is considered as an indicator of thermal aging in fatigue life modeling for the low alloy steel. Finally, a novel life model that incorporates both aging time and temperature was proposed for rapid prediction of low cycle fatigue life. It is assumed that this model promotes reliable fatigue life prediction in low alloy steels under various thermal aging circumstances, as well as the extrapolation of fatigue performance of the material in service.

材料的疲劳失效对设备的使用安全有很大影响。实验结果表明，在这种情况下，试样的极限强度和屈服强度适度提高，而疲劳寿命却略有下降。断裂分析表明，贝氏体断裂有利于热时效后疲劳裂纹的萌发和扩展，同时伴随着塑性应变振幅的减小。因此，在低合金钢的疲劳寿命模型中，塑性应变振幅被视为热老化的一个指标。最后，为了快速预测低循环疲劳寿命，我们提出了一种包含老化时间和温度的新型寿命模型。假定该模型能可靠地预测低合金钢在各种热老化情况下的疲劳寿命，并推断材料在使用中的疲劳性能。

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引用次数: 0

A study into the impact of tooth root transition curve morphology on the bending fatigue life of gears 齿根过渡曲线形态对齿轮弯曲疲劳寿命影响的研究

IF 5.7 2区材料科学 Q1 ENGINEERING, MECHANICAL

International Journal of Fatigue

Pub Date : 2024-10-11 DOI: 10.1016/j.ijfatigue.2024.108643

Cheng Wang

Tooth fracture is a prevalent failure mode that is intimately related to the bending strength of gears. Among the myriad factors influencing gear bending fatigue life, the morphology of the tooth root transition curve stands out as a crucial one, intricately tied to the gear’s resistance to bending fatigue. However, despite its significance, related research efforts, particularly experimental studies that consider cost factors, are relatively scarce in the current research landscape. Therefore, this paper first theoretically examines the influence of the tooth root transition curve morphology on the bending stress of gear teeth. Subsequently, bending fatigue experiments are conducted on gears featuring three typical tooth root transition curve morphologies, and the S-N curves for gears with these different morphologies are summarized. The findings reveal that adopting the digging-root type tooth root transition curve processing method, coupled with appropriately increasing the radius of the tooth top transition curve on the rack cutter, suitably reducing the distance between the rack tooth profile line and the tangent of the tooth root transition curve, and meticulously controlling the roughness of the tooth root transition curve, will significantly enhance the bending fatigue strength and prolong the bending fatigue life of the gear.

齿断裂是一种普遍的失效模式，与齿轮的弯曲强度密切相关。在影响齿轮弯曲疲劳寿命的众多因素中，齿根过渡曲线的形态是一个关键因素，与齿轮的抗弯曲疲劳性能密切相关。然而，尽管其重要性不言而喻，相关的研究工作，尤其是考虑成本因素的实验研究，在目前的研究领域却相对匮乏。因此，本文首先从理论上研究了齿根过渡曲线形态对齿轮齿弯曲应力的影响。随后，对具有三种典型齿根过渡曲线形态的齿轮进行了弯曲疲劳实验，并总结了具有这些不同形态的齿轮的 S-N 曲线。研究结果表明，采用掘根式齿根过渡曲线加工方法，同时适当增大齿条切刀上齿顶过渡曲线的半径，适当减小齿条齿廓线与齿根过渡曲线切线之间的距离，细致控制齿根过渡曲线的粗糙度，可显著提高齿轮的弯曲疲劳强度，延长弯曲疲劳寿命。

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引用次数: 0

Physics-informed Gaussian process regression model for predicting the fatigue life of welded joints 用于预测焊接接头疲劳寿命的物理信息高斯过程回归模型

IF 5.7 2区材料科学 Q1 ENGINEERING, MECHANICAL

International Journal of Fatigue

Pub Date : 2024-10-10 DOI: 10.1016/j.ijfatigue.2024.108644

Dukyong Kim , Dong-Yoon Kim , Taehwan Ko , Seung Hwan Lee

Fatigue failure in welded joints substantially threatens the reliability of engineering structures. To address this issue, this study proposes a novel hybrid physics-informed Gaussian process regression (Pi-GPR) model to predict the fatigue life of welded joints. The Pi-GPR model is advantageous in reducing the model’s dependency on extensive experimental datasets by integrating physical features from fatigue fracture mechanics. Unlike previously developed fatigue life prediction models, the Pi-GPR model uniquely addresses nonlinear characteristics of welding and fatigue testing while simultaneously quantifying the prediction uncertainty stemming from the variability of testing parameters. Spearman’s rank correlation analysis method identified cross-sectional geometry features highly correlated with fatigue life, incorporating these physical features into the Pi-GPR model. Notably, the Pi-GPR model used easily measurable length-related physical features to provide comprehensive geometrical information, demonstrating exceptional prediction performance and offering confidence intervals for each result. Furthermore, the Pi-GPR model maintained superior prediction accuracy even with minimal training data, thus confirming its low data dependency.

焊接接头的疲劳失效严重威胁着工程结构的可靠性。为解决这一问题，本研究提出了一种新颖的混合物理信息高斯过程回归（Pi-GPR）模型来预测焊接接头的疲劳寿命。Pi-GPR 模型的优势在于通过整合疲劳断裂力学的物理特征，减少了模型对大量实验数据集的依赖。与之前开发的疲劳寿命预测模型不同，Pi-GPR 模型独特地解决了焊接和疲劳测试的非线性特征，同时量化了测试参数变化带来的预测不确定性。斯皮尔曼秩相关分析方法确定了与疲劳寿命高度相关的横截面几何特征，并将这些物理特征纳入了 Pi-GPR 模型。值得注意的是，Pi-GPR 模型使用易于测量的长度相关物理特征来提供全面的几何信息，显示出卓越的预测性能，并为每个结果提供置信区间。此外，即使训练数据极少，Pi-GPR 模型也能保持卓越的预测准确性，从而证实了该模型对数据的依赖性很低。

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引用次数: 0

Very high cycle fatigue behavior of TC4 titanium alloy: Faceting cracking mechanism and life prediction based on dislocation characterization TC4 钛合金的超高循环疲劳行为：基于位错表征的面状开裂机理和寿命预测

IF 5.7 2区材料科学 Q1 ENGINEERING, MECHANICAL

International Journal of Fatigue

Pub Date : 2024-10-09 DOI: 10.1016/j.ijfatigue.2024.108640

Hailong Deng , Jie Liu , Heming Kang , Yupeng Guo , Liming Song , Huan Yu

This research analyzes the very-high-cycle-fatigue behavior of TC4 titanium alloy through fatigue tests at R = −1, −0.3, and 0.1. The results show that the S-N curves are all bilinear and exhibit three failure modes as surface slip failure, surface cleavage failure and interior cleavage failure. Transmission electron microscopy analysis reveals the dislocation structure in interior cleavage failure and suggests that the deformation mechanism of faceting cracking involves both anti-phase boundary shearing and stacking fault shearing mechanisms. It concludes that interior failure results from cleavage fracture of α grains due to dislocation slip. Based on the stress intensity factor of the maximum defect, a slip-cleavage competitive failure model was developed by considering factors such as control volume, defect size, external loading, and grain content, with good predictive results. Additionally, on the basis of the failure mechanism and crack propagation rate model, considering the coupled effects of crack tip blunting, stress ratio, Vickers hardness, and material fracture toughness on crack propagation, the crack propagation life prediction model is constructed. The life prediction model is further modified to be more conservative and accurate in predicting life by consideration the maximum defect size, providing important theoretical support and practical guidance for engineering applications.

本研究通过 R =-1、-0.3 和 0.1 下的疲劳试验，分析了 TC4 钛合金的超高循环疲劳行为。结果表明，S-N 曲线均为双线性，并呈现出表面滑移破坏、表面劈裂破坏和内部劈裂破坏三种破坏模式。透射电子显微镜分析揭示了内部劈裂破坏中的位错结构，并认为面裂的变形机制涉及反相边界剪切和堆积断层剪切机制。研究得出结论，内部破坏是由于位错滑移造成的 α 晶粒劈裂断裂。根据最大缺陷的应力强度因子，考虑控制体积、缺陷尺寸、外部载荷和晶粒含量等因素，建立了滑移-劈裂竞争性破坏模型，并取得了良好的预测效果。此外，在失效机理和裂纹扩展速率模型的基础上，考虑裂纹尖端钝化、应力比、维氏硬度和材料断裂韧性对裂纹扩展的耦合效应，构建了裂纹扩展寿命预测模型。通过考虑最大缺陷尺寸，进一步修正了寿命预测模型，使其在预测寿命方面更加保守和准确，为工程应用提供了重要的理论支持和实践指导。

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引用次数: 0

Cross-scale early damage mechanism of VHCF based on the initiation and evolution of fine granular area in selective laser melting Ti-6Al-4 V alloy 基于选择性激光熔炼 Ti-6Al-4 V 合金中细粒区的形成和演变的 VHCF 跨尺度早期损伤机制

IF 5.7 2区材料科学 Q1 ENGINEERING, MECHANICAL

International Journal of Fatigue

Pub Date : 2024-10-09 DOI: 10.1016/j.ijfatigue.2024.108641

Guanze Sun , Zhao Tian , Zihua Zhao

Due to the initiation of fine granular area inside the material and the formation of nanoscale grains, it is difficult to conduct in-situ observation and high-scale characterization. This is the main reason why the formation mechanism of fine granular area in very high cycle fatigue has been unknown and controversial. Therefore, on the basis of fracture analysis method to invert the fine granular area formation, we further put forward an experimental proposal whether a microcrack in the fine granular area formation stage can be prepared to observe the critical event of early damage evolution. Here, we selected selective laser melting Ti-6Al-4 V alloy with inherent defects as the model material to obtain significant defect-initiating fine granular areas, found two secondary microcracks after dissecting along the defects, and then carried out multiscale characterization and quantitative analysis of main cracks and secondary cracks. We found that the fine grains originate from the severe plastic deformation in local of crack tip plastic zone and lowered the cracking threshold by the grain boundary sliding between the hard-oriented grains, which results in grain refinement, cavitation and cracking. This work systematically describes damage evolution mechanism, which has guiding significance for the reliability evaluation and fatigue resistance design of materials.

由于细颗粒区是在材料内部形成的，而且是纳米级颗粒，因此很难进行原位观测和高尺度表征。这也是超高循环疲劳中细颗粒区形成机理一直不明且存在争议的主要原因。因此，我们在断裂分析方法反演细颗粒区形成的基础上，进一步提出了能否在细颗粒区形成阶段制备微裂纹以观察早期损伤演化临界事件的实验方案。在此，我们选择了具有固有缺陷的选择性激光熔炼 Ti-6Al-4 V 合金作为模型材料，获得了显著的缺陷引发细颗粒区，沿缺陷剖析后发现了两条次生微裂纹，然后对主裂纹和次生裂纹进行了多尺度表征和定量分析。我们发现，细晶粒源于裂纹尖端塑性区局部的严重塑性变形，并通过硬取向晶粒间的晶界滑动降低了开裂阈值，从而导致晶粒细化、空化和开裂。该研究系统地阐述了损伤演化机理，对材料的可靠性评价和抗疲劳设计具有指导意义。

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引用次数: 0

Fatigue crack closure assessment by wavelet transform of infrared thermography signals 利用红外热成像信号的小波变换评估疲劳裂纹闭合情况

IF 5.7 2区材料科学 Q1 ENGINEERING, MECHANICAL

International Journal of Fatigue

Pub Date : 2024-10-05 DOI: 10.1016/j.ijfatigue.2024.108639

Lorenzo Bercelli, Bruno Levieil, Cédric Doudard, Sylvain Calloch

The occurrence of crack closure significantly impacts the fatigue life of materials and structural components. Whether it is induced by the nature of the loading, the fabrication process or the geometry of the structure, its magnitude and effect should be considered to further improve predictive models of fatigue crack propagation. However, the definition of reliable experimental methods for the observation and assessment of fatigue crack closure, and in particular suited to structure testing, remains a challenge. The present study aims to provide a novel approach for the assessment of fatigue crack closure via the continuous wavelet transform of infrared thermography data. The processing of the temperature signal close to the crack in a coherent time–frequency space allows for the identification of crack closing and opening instants associated with high-frequency components. The method is meant to be suited to any testing configuration (conventional compact tension specimen or full-scale structures) with minimum operator-dependent parameters.

裂纹闭合的发生会对材料和结构部件的疲劳寿命产生重大影响。无论是由载荷性质、制造工艺还是结构的几何形状引起的裂纹闭合，都应考虑其程度和影响，以进一步改进疲劳裂纹扩展的预测模型。然而，如何确定观察和评估疲劳裂纹闭合的可靠实验方法，特别是适合结构测试的方法，仍然是一项挑战。本研究旨在通过红外热成像数据的连续小波变换，提供一种评估疲劳裂纹闭合的新方法。在相干时频空间中处理裂纹附近的温度信号，可识别与高频成分相关的裂纹闭合和打开瞬间。该方法适用于任何测试配置（传统的紧凑型拉伸试样或全尺寸结构），只需最小的操作员相关参数。

引用次数: 0

Damage evolution simulation and lifetime prediction for composite blades under continuous droplet impacts 复合材料叶片在连续液滴冲击下的损伤演变模拟和寿命预测

IF 5.7 2区材料科学 Q1 ENGINEERING, MECHANICAL

International Journal of Fatigue

Pub Date : 2024-10-05 DOI: 10.1016/j.ijfatigue.2024.108638

Jianyu Zhang , Wenhao Xu , Xiaozhong Du , Xu Guo

Offshore wind power generation is a promising technology in renewable energy applications due to its high reserves of wind energy in sea areas. To improve the energy transformation efficiency, the blade length of the offshore wind turbines has become larger and larger, and it has made rain erosion be one of the most frequent failures during the turbine operation. As the natural rainfall is stochastic in spatial and time domains, it is difficult to depict the damage evolution process caused by rain impact exactly. Therefore, regular and continuous droplet impact simulation and experiments present an alternative methodology for this issue. With the composite structure of the blade and deformability of the liquid droplet in consideration, a fluid solid interaction model will be established to investigate the impact response and subsequent damage evolution. In which, the Smooth Particle Hydrodynamics (SPH) model is utilized to depict the constitutive relationship within the droplet, and Finite Element Method (FEM) is used to construct the Representative Volume Element (RVE) model of the blade leading edge. The impact process is simulated first to obtain the impact pressure distribution at the contact center and velocity field in the droplet. Furthermore, the stress wave propagation in the blade multilayer structure can be analyzed. Owing to the multiaxial fatigue feature of the continuous droplet impact, the continuum damage mechanics is integrated with the fatigue criterion and the Jump-in-Cycle procedure is used to simulate the high-cycle fatigue process. The damage factor distribution on the blade coating surface and its influence on mechanical properties are analyzed. Thereafter, the droplet impact fatigue life can be accumulated based on Miner’s linear rules. The theoretical achievements are validated by experimental data provided by Rain Erosion Testing (RET), which shows a good agreement between each other. As a result, V-N curves and D-N curves, i.e. quantitative relationship between droplet falling conditions and impact fatigue life, are established. The achievements in this study can provide an effective tool for rain erosion mechanism analysis and life prediction in industrial applications.

由于海域风能储量大，海上风力发电是一项前景广阔的可再生能源应用技术。为了提高能量转换效率，海上风力涡轮机的叶片长度越来越大，这使得雨水侵蚀成为涡轮机运行过程中最常见的故障之一。由于自然降雨在空间域和时间域上都是随机的，很难准确描述雨水冲击造成的破坏演变过程。因此，有规律的连续水滴冲击模拟和实验为这一问题提供了一种替代方法。考虑到叶片的复合结构和液滴的变形性，将建立一个流固相互作用模型来研究冲击响应和随后的损伤演变。其中，利用平滑粒子流体动力学（SPH）模型来描述液滴内部的构成关系，并利用有限元法（FEM）来构建叶片前缘的代表性体积单元（RVE）模型。首先模拟冲击过程，以获得接触中心的冲击压力分布和液滴中的速度场。此外，还可以分析叶片多层结构中的应力波传播。由于连续液滴冲击具有多轴疲劳特征，因此将连续损伤力学与疲劳准则相结合，采用循环跳跃程序模拟高循环疲劳过程。分析了叶片涂层表面的损伤因子分布及其对机械性能的影响。之后，根据 Miner 的线性规则可以累计液滴冲击疲劳寿命。雨水侵蚀测试（RET）提供的实验数据对理论成果进行了验证，结果表明两者之间具有良好的一致性。因此，建立了 V-N 曲线和 D-N 曲线，即水滴下落条件与冲击疲劳寿命之间的定量关系。本研究的成果可为工业应用中的雨蚀机理分析和寿命预测提供有效工具。

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引用次数: 0

A cGAN-based fatigue life prediction of 316 austenitic stainless steel in high-temperature and high-pressure water environments 基于 cGAN 的 316 奥氏体不锈钢在高温高压水环境下的疲劳寿命预测方法

IF 5.7 2区材料科学 Q1 ENGINEERING, MECHANICAL

International Journal of Fatigue

Pub Date : 2024-10-05 DOI: 10.1016/j.ijfatigue.2024.108633

Lvfeng Jiang , Yanan Hu , Hui Li , Xuejiao Shao , Xu Zhang , Qianhua Kan , Guozheng Kang

The thermo-mechanical-chemical coupling effect presents significant challenges in accurately predicting the fatigue life of 316 austenitic stainless steel in high-temperature and high-pressure water environments (referred to hereafter as environmental fatigue). The complexity of environmental fatigue experiments results in limited and dispersed data, further making the life prediction difficult. Traditional fatigue life prediction models are often constrained by specific loading conditions and do not adequately account for the complex environmental influences. To address these issues, this paper proposes a novel environmental fatigue life prediction model of 316 stainless steel utilizing conditional Generative Adversarial Networks. The proposed model incorporates critical environmental factors, loading conditions and stacking fault energy, allowing direct prediction of environmental fatigue life. A comparative analysis on the predicted and experimental results reveals that the cGAN-based model significantly improves the prediction accuracy, reducing the fatigue life prediction error from a factor of 5 to within 3. To quantify the uncertainty in fatigue life prediction, the Monte Carlo Dropout method is employed to enable a probabilistic assessment of fatigue life. Furthermore, four environmental and loading conditions are established to evaluate the model’s extrapolation capability. The results demonstrate that the probabilistic fatigue assessment effectively captures data distribution and achieves high prediction accuracy.

热机械-化学耦合效应给准确预测 316 奥氏体不锈钢在高温高压水环境下的疲劳寿命（以下简称环境疲劳）带来了巨大挑战。环境疲劳实验的复杂性导致数据有限且分散，进一步增加了寿命预测的难度。传统的疲劳寿命预测模型往往受到特定加载条件的限制，无法充分考虑复杂的环境影响因素。为解决这些问题，本文提出了一种利用条件生成对抗网络的新型 316 不锈钢环境疲劳寿命预测模型。该模型结合了关键环境因素、加载条件和堆叠故障能量，可直接预测环境疲劳寿命。对预测结果和实验结果的对比分析表明，基于 cGAN 的模型显著提高了预测精度，将疲劳寿命预测误差从 5 倍降低到 3 倍以内。此外，还确定了四种环境和负载条件，以评估模型的外推能力。结果表明，概率疲劳评估能有效捕捉数据分布，并实现较高的预测精度。

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引用次数: 0