International Journal of Fatigue最新文献_第7页

Data driven topology optimization of AM parts accounting for process-affected fatigue performance: Application to automotive and aerospace components 考虑工艺影响疲劳性能的增材制造零件的数据驱动拓扑优化：在汽车和航空航天部件上的应用

IF 6.8 2区材料科学 Q1 ENGINEERING, MECHANICAL

International Journal of Fatigue

Pub Date : 2026-01-07 DOI: 10.1016/j.ijfatigue.2026.109481

Alessio Centola , Alberto Ciampaglia , Carlo Boursier Niutta , Filippo Berto , Davide Salvatore Paolino , Andrea Tridello

The present paper presents two novel data-driven topology optimization (TO) procedures to design lighter additively manufactured (AM) fatigue resistant components. The first TO method is driven by a probabilistic machine learning (ML) algorithm based on a Bayesian Neural Network (BNN), trained on fatigue data from the literature to assess probabilistic stress-life (PSN) curves. These curves are used to predict the allowable design stress for TO and are predicted directly from AM process parameters, the risk volume, and thermal and surface treatments. The second TO design procedure is instead driven by another BNN, trained to predict the maximum critical defect size from the process parameters. The TO limit stress is computed from the predicted critical defect and the threshold stress intensity factor K_th. After the TO, the critical stress intensity factor K_I in the component is computed and compared against K_th, to assess the effectiveness of this design procedure. These two frameworks are applied to the design of an SS316L automotive suspension lower control arm and a Ti6Al4V aerospace bracket, respectively. With the following framework, the limit stress calculation does not require specifically designed experimental campaigns and prototyping, as previously sparse experimental knowledge can be embedded in a powerful design tool, which allows for preventing fatigue failures, while accounting directly for the influence of the AM process parameters.

本文提出了两种新的数据驱动拓扑优化（TO）方法来设计更轻的增材制造（AM）抗疲劳部件。第一种TO方法由基于贝叶斯神经网络（BNN）的概率机器学习（ML）算法驱动，该算法根据文献中的疲劳数据进行训练，以评估概率应力寿命（PSN）曲线。这些曲线用于预测to的允许设计应力，并直接从增材制造工艺参数、风险体积、热处理和表面处理中进行预测。第二个TO设计程序由另一个BNN驱动，该BNN经过训练，可以从工艺参数中预测最大临界缺陷尺寸。根据预测的临界缺陷和阈值应力强度因子Kth计算极限应力。在TO之后，计算组件中的临界应力强度因子KI并与Kth进行比较，以评估该设计过程的有效性。这两种框架分别应用于SS316L汽车悬架下控制臂和Ti6Al4V航空航天支架的设计。有了下面的框架，极限应力计算不需要专门设计的实验活动和原型，因为以前稀疏的实验知识可以嵌入到一个强大的设计工具中，这可以防止疲劳失效，同时直接考虑到增材制造工艺参数的影响。

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引用次数: 0

Fitting of an FCG test of the WE43C and AA7050 alloys using two phase-fields and a Constant-ΔK approach 采用两相场和常数-ΔK方法拟合WE43C和AA7050合金的FCG测试

IF 6.8 2区材料科学 Q1 ENGINEERING, MECHANICAL

International Journal of Fatigue

Pub Date : 2026-01-06 DOI: 10.1016/j.ijfatigue.2026.109483

Matheus Garcia do Vale , Thiago Roberto Felisardo Cavalcante , Gualter Silva Pereira , Julián Arnaldo Ávila Díaz , José Luiz Boldrini , Marco Lúcio Bittencourt

Fatigue crack growth critically influences the lifespan of structural components in high-demanding engineering applications. Despite advances in phase-field fracture models, cycle-by-cycle simulations remain computationally prohibitive and often rely on extrapolation techniques. This work introduces a novel energy-based fatigue degradation evolution equation within a phase-field framework, enabling direct recovery of the Paris-law behavior without the need for explicit cycle-jumping algorithms. We implement a staggered solution scheme and employ a constant-

Δ K

loading procedure to compute crack growth rates in selected stress intensity ranges. The proposed strategy is effective in calibrating simulation parameters, resulting in a reduction of up to 97% in simulated cycles. Additionally, we utilize an automatic crack length measurement algorithm based on the A* pathfinder heuristic, which minimizes user intervention and mesh dependence. Validation with experimental data for the WE43 and AA7050 alloys shows excellent agreement in the Paris plots, while reducing computational costs. The proposed methodology offers a robust and efficient tool for material characterization and fatigue analysis in brittle-to-ductile materials.

在高要求的工程应用中，疲劳裂纹扩展严重影响结构部件的寿命。尽管相场裂缝模型取得了进展，但循环模拟仍然难以进行计算，而且通常依赖于外推技术。这项工作在相场框架内引入了一种新的基于能量的疲劳退化演化方程，可以直接恢复巴黎定律行为，而不需要显式的周期跳变算法。我们实现了交错解决方案，并采用恒定-ΔK加载程序来计算选定应力强度范围内的裂纹扩展速率。所提出的策略在校准模拟参数方面是有效的，导致模拟周期减少高达97%。此外，我们利用基于A*探路者启发式的裂缝长度自动测量算法，最大限度地减少了用户干预和网格依赖。WE43和AA7050合金的实验数据验证表明，在巴黎图中具有良好的一致性，同时降低了计算成本。所提出的方法为脆性到延性材料的材料表征和疲劳分析提供了一个强大而有效的工具。

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引用次数: 0

Fatigue behavior of externally bonded and hybrid-bonded carbon fiber reinforced polymer–to–concrete joints 外粘接和混合粘接碳纤维增强聚合物-混凝土节点的疲劳性能

IF 6.8 2区材料科学 Q1 ENGINEERING, MECHANICAL

International Journal of Fatigue

Pub Date : 2026-01-04 DOI: 10.1016/j.ijfatigue.2026.109482

Mehdi Aghabagloo , Laura Carreras , José Sena-Cruz , Marta Baena

Although the bond behavior and failure modes of externally bonded reinforcement (EBR) fiber-reinforced polymer (FRP) and hybrid-bonded (HB) systems on concrete have been widely investigated under quasi-static loading, their performance under fatigue loading remains insufficiently understood. Existing research on RC structures strengthened with carbon FRP (CFRP) under cyclic loading has predominantly focused on demonstrating improvements in fatigue life. However, far less attention has been given to examining the bond behavior and the rate of debonding growth, factors that are critical to ensuring the long-term effectiveness and durability of externally bonded CFRP systems. This study experimentally examines the performance of EBR and HB CFRP-to-concrete bonded joints subjected to cyclic fatigue loading. The investigation focuses on the progression of fatigue-induced damage in bonded joints tested under direct pull-out conditions, using CFRP laminates exposed to different maximum cyclic load levels (relative to the static failure load) while keeping a constant load ratio. Under fatigue loading, interfacial debonding between the CFRP laminate and the adhesive was observed, whereas quasi-static tests typically resulted in cohesive failure within the concrete. Results also revealed that increasing the maximum cyclic load markedly accelerated the rate of debonding propagation.

尽管在准静态载荷作用下，外粘结增强（EBR）、纤维增强聚合物（FRP）和混合粘结（HB）体系在混凝土上的粘结行为和破坏模式已经得到了广泛的研究，但它们在疲劳载荷作用下的性能仍然不够清楚。目前对循环荷载下碳纤维增强混凝土结构的研究主要集中在提高疲劳寿命上。然而，对于检查粘结行为和脱粘增长速度的关注远远不够，这些因素对于确保外部粘结CFRP系统的长期有效性和耐久性至关重要。本研究对EBR和HB cfrp -混凝土粘结节点在循环疲劳荷载下的性能进行了试验研究。该研究的重点是在直接拔出条件下，使用CFRP层叠板暴露于不同的最大循环荷载水平（相对于静态破坏荷载），同时保持恒定的荷载比，测试粘结接头疲劳损伤的进展。在疲劳荷载下，观察到CFRP层压板和粘合剂之间的界面剥离，而准静态试验通常导致混凝土内部的粘结破坏。结果还表明，增加最大循环荷载显著加快了脱粘的传播速度。

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引用次数: 0

Crystallographic characteristics of fatigue crack propagation across α/β phase boundary in Zr-2.5Nb alloy Zr-2.5Nb合金疲劳裂纹跨α/β相扩展的晶体学特征

IF 6.8 2区材料科学 Q1 ENGINEERING, MECHANICAL

International Journal of Fatigue

Pub Date : 2026-01-03 DOI: 10.1016/j.ijfatigue.2025.109480

Kangkai Song , Conghui Zhang , Tongguang Zhai , Wenguang Zhu , Shuaiyang Liu , Ruixuan Tian , Guoliang Liu , Jinping Wang

Understanding fatigue crack propagation (FCP) in Zr-2.5Nb alloy is crucial for safely shutting down the reactor before crack propagation to instability. This study quantitatively investigated the FCP behavior in a α/β Zr-2.5Nb alloy in combination with four crystallographic parameters (geometric compatibility factor (m’), Schmidt factor (SF), effective driving force (D), and twist angle (

φ

)). The results indicated that the strength and initial crack propagation resistance were improved with the increase of the β-phase. However, the initial FCP rate increased when the α-martensitic transformation occurred in the β-phase. Quantitative analysis indicated that transgranular cracks propagate primarily along prismatic and pyramidal planes in α phase, while along the (1 1 0) and (1 1 1) planes in the β phase. Cracks propagated along the slip plane if SF >0.3 and D <0.7, but along the plane of maximum driving planes if D >0.7 and SF <0.3. FCP across the phase boundary was related to

φ

and m’; crack deflection was significantly observed at the phase boundary when

φ

> 40° and m’ < 0.4. Finally, the effects of residual β phase and martensitic transformation on the crack growth rate were discussed. This work contributes to understanding the critical role of the β phase in FCP within Zr alloys and provides new ideas for enhancing FCP resistance.

了解Zr-2.5Nb合金的疲劳裂纹扩展（FCP）对于在裂纹扩展到不稳定之前安全关闭反应堆至关重要。结合几何相容因子（m′）、施密特因子（SF）、有效驱动力(D)和扭转角（φ）四个晶体学参数，定量研究了α/β Zr-2.5Nb合金的FCP行为。结果表明，随着β相含量的增加，合金的强度和抗初始裂纹扩展能力均有所提高。当α-马氏体相变发生时，初始FCP速率增加。定量分析表明，α相的穿晶裂纹主要沿棱柱面和锥体面扩展，β相的穿晶裂纹主要沿（11 - 10）和（11 - 11）面扩展。当SF >；0.3和D <；0.7时裂纹沿滑移面扩展，当D >；0.7和SF <；0.3时裂纹沿最大驱动面扩展。跨相界的FCP与φ和m′有关；当φ >； 40°和m ' <； 0.4°时，在相界处观察到明显的裂纹偏转。最后讨论了残余β相和马氏体相变对裂纹扩展速率的影响。这项工作有助于理解β相在Zr合金中FCP的关键作用，并为提高FCP抗性提供了新的思路。

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引用次数: 0

Fatigue behavior of laser powder bed fusion GH4169 superalloy using different heat treatment methods 激光粉末床熔合GH4169高温合金不同热处理方式的疲劳行为

IF 6.8 2区材料科学 Q1 ENGINEERING, MECHANICAL

International Journal of Fatigue

Pub Date : 2026-01-03 DOI: 10.1016/j.ijfatigue.2025.109479

Tao Shi , Yadong Zhou , Ruiyang Li , Feng Zhang , Jingyu Sun , Guian Qian

GH4169 superalloy was manufactured by laser powder bed fusion process, and the effects of two types of heat treatment strategies (solution + aging (SA), and hot isostatic pressing + solution + aging (HSA)) on superalloy microstructure evolution and fatigue performance were studied. A detailed microstructural characterization of the initial material and fatigue failure specimen was carried out, and it was found that HSA treatment eliminated the cellular and lamellar substructures of the material, increased the grain size, reduced dislocation density and the size of precipitates, thereby reducing the fatigue resistance compared to SA-treated material. In addition, different types of strengthening mechanisms were superimposed to estimate the yield strength of these two types of heat-treated materials. Finally, a crystal plasticity finite element model combined with thermodynamic entropy generation was established to predict fatigue life.

采用激光粉末床熔合法制备了GH4169高温合金，研究了固溶+时效（SA）和热等静压+固溶+时效（HSA）两种热处理策略对高温合金组织演变和疲劳性能的影响。对初始材料和疲劳破坏试样进行了详细的微观组织表征，发现与sa处理的材料相比，HSA处理消除了材料的细胞和片层亚结构，增加了晶粒尺寸，降低了位错密度和析出相的尺寸，从而降低了疲劳抗力。此外，通过叠加不同类型的强化机制来估计这两种热处理材料的屈服强度。最后，建立了结合热力学熵生成的晶体塑性有限元模型来预测疲劳寿命。

引用次数: 0

Crack initiation mechanisms of linear friction welded dissimilar Ti60/TC17 joint in very high cycle fatigue regime at different temperatures 不同温度下异种Ti60/TC17接头高周疲劳状态下线摩擦焊接裂纹萌生机理

IF 6.8 2区材料科学 Q1 ENGINEERING, MECHANICAL

International Journal of Fatigue

Pub Date : 2026-01-03 DOI: 10.1016/j.ijfatigue.2025.109478

Tian Xu , Huwei Qiu , Wentao Huang , Delong He , Yao Chen , Chong Wang , Qingyuan Wang , Jinbo Bai , Fulin Liu , Yongjie Liu

To meet the application requirements for aero-engine Blisks, very high cycle fatigue (VHCF) behavior of Ti60/TC17 linear friction welded (LFW) joints was investigated at room temperature (RT) and high temperatures (HT). The results indicate that fatigue strength decreases with increasing temperature. Fatigue fractures predominantly occur in the weaker Ti60 base material at all test temperatures. Nearly all fatigue crack initiation sites are characterized by facet morphologies formed through the cleavage of α grains. Specifically, subsurface failures originate from an oversized facet, whereas internal failures arise from facet clusters. Microstructural analysis reveals that cracks primarily nucleate at the α/β phase interface and along slip bands within equiaxed α grains. Notably, high temperature significantly influences the crack initiation mechanism, causing a transition in facet formation from basal slip dominance at RT to synergistic basal and prismatic slip at HT. Furthermore, for subsurface crack initiation at HT, the synergistic effect of prolonged high-temperature exposure and dislocation-assisted oxygen diffusion facilitates brittle oxide formation at the crack tips, thereby accelerating fatigue failure.

为了满足航空发动机Blisks的应用要求，研究了Ti60/TC17线性摩擦焊接接头在室温和高温下的甚高周疲劳行为。结果表明，随着温度的升高，材料的疲劳强度逐渐降低。在所有测试温度下，疲劳断裂主要发生在较弱的Ti60基材中。几乎所有的疲劳裂纹起裂部位都以α晶粒解理形成的小面形貌为特征。具体来说，地下故障源于过大的关节面，而内部故障则源于关节面簇。显微组织分析表明，裂纹主要在α/β相界面和等轴α晶粒内沿滑移带形核。值得注意的是，高温显著影响了裂纹的起裂机制，导致小面形成从高温时的基底滑移为主转变为高温时的基底滑移和棱柱滑移协同作用。此外，对于高温下的地下裂纹萌生，长时间高温暴露和位错辅助的氧扩散的协同作用促进了裂纹尖端脆性氧化物的形成，从而加速了疲劳破坏。

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引用次数: 0

Oxidation-induced crack initiation and propagation behaviors of Ni-based single crystal superalloy in VHCF regime 镍基单晶高温合金VHCF氧化致裂纹萌生与扩展行为

IF 6.8 2区材料科学 Q1 ENGINEERING, MECHANICAL

International Journal of Fatigue

Pub Date : 2026-01-01 DOI: 10.1016/j.ijfatigue.2025.109461

Yang Meng, Chungen Zhou, Kezhi huang, Leyu Li, Zihua Zhao

The interaction between oxidation and fatigue under lower stress in Ni-based single crystal superalloys remains insufficiently explored. In this study, a newly designed notched plate specimen was developed for VHCF testing at 1000 °C to investigate these phenomena. Quasi-in-situ observations were employed to monitor crack initiation and crack propagation processes. The results shown that all fatigue cracks initiated at the notch root and propagated in a Mode I manner. The fracture surface consists of two distinct regions, an oxidation-dominate zone (ODZ) characterized by extensive oxide coverage, and the fatigue-dominated zone (FDZ) marked by clear fatigue striations. Over 90 % of the total fatigue life was spent in the ODZ. As cracks propagated, thermally grown stress in the oxide near the crack tip altered the local stress field, promo6ting γ′ rafting and aluminum diffusion. These effects transformed the crack-tip oxide from a multilayered structure to a continuous Al₂O₃-rich scale. Within the ODZ, oxidation-induced crack closure suppressed crack growth, rendering the oxidation rate the dominant factor controlling the crack propagation rate. When the effective stress intensity factor exceeded a critical threshold, oxidation penetrated to the γ/γ′ interface within the substrate, triggering a transition from ODZ to FDZ and accelerating crack growth. Overall, these findings confirm that enhancing oxidation resistance is still critical for improving VHCF performance in Ni-based single crystal superalloys.

镍基单晶高温合金在低应力条件下氧化与疲劳的相互作用尚未得到充分的研究。在本研究中，开发了一种新设计的缺口板试件，用于1000°C的VHCF测试，以研究这些现象。采用准原位观测方法监测裂纹萌生和扩展过程。结果表明：所有疲劳裂纹均从缺口根部开始，并以I型方式扩展；断口表面由两个不同的区域组成，氧化主导区（ODZ）以广泛的氧化覆盖为特征，疲劳主导区（FDZ）以明显的疲劳条纹为特征。超过90%的总疲劳寿命是在ODZ中度过的。随着裂纹的扩展，裂纹尖端附近氧化物中的热生长应力改变了局部应力场，促进了γ′的漂移和铝的扩散。这些作用使裂纹尖端的氧化物从多层结构转变为连续的富al2o3鳞片。在ODZ内，氧化诱导的裂纹闭合抑制裂纹扩展，使氧化速率成为控制裂纹扩展速率的主导因素。当有效应力强度因子超过临界阈值时，氧化渗透到基体内的γ/γ′界面，触发从ODZ到FDZ的转变，加速裂纹扩展。总的来说，这些发现证实了增强抗氧化性仍然是提高ni基单晶高温合金VHCF性能的关键。

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引用次数: 0

Fatigue damage development and mechanical property degradation of pearlitic rail steel under loaded traffic 珠光体轨道钢承载疲劳损伤发展及力学性能退化

IF 6.8 2区材料科学 Q1 ENGINEERING, MECHANICAL

International Journal of Fatigue

Pub Date : 2025-12-31 DOI: 10.1016/j.ijfatigue.2025.109474

Manjiang Yu , Ye Wang , Fangli Duan , Chaofeng Lü

The service failure evaluation of the damaged rail can provide theoretical guidance for the routine maintenance of existing railway lines. In this work, U71MnG rail that failed under traffic loading is selected to investigate the fatigue damage mechanism of pearlitic rail steel. In addition to the conventional surface crack, the branch crack characterized by the ‘Y’ at the subsurface inclusion is also observed. Among them, the leading crack aligned with the rolling direction forms and propagates first, followed by the two trailing cracks propagating in the reverse rolling direction. Driven by the plastic ratcheting at the surface layer and the deeper bending deformation, these two trailing cracks may converge with other adjacent leading cracks, resulting in the formation of the spalling pit hundreds of μm deep. Moreover, the sliding friction in the transverse direction of the rail promotes the formation of wavy pearlite, which reduces the fracture toughness of the outside rail. In the predictive maintenance of rails, it is essential to promptly identify and address potential hazards of surface spalling and transverse fracture.

损坏钢轨的服务失效评估可以为既有铁路线路的日常维护提供理论指导。选取在交通荷载作用下失效的u71mg钢轨，研究珠光体钢轨钢的疲劳损伤机理。除常规表面裂纹外，在亚表面夹杂处还观察到以“Y”形为特征的分支裂纹。其中，与轧制方向一致的先导裂纹首先形成并扩展，其次是与轧制方向相反的两个尾随裂纹。在表层的塑性棘轮和较深的弯曲变形的驱动下，这两条拖尾裂纹可能与相邻的其他超前裂纹汇合，形成数百μm深的剥落坑。此外，钢轨横向滑动摩擦促进波浪形珠光体的形成，降低了钢轨外侧的断裂韧性。在钢轨的预测性维护中，及时识别和处理表面剥落和横向断裂的潜在危险是至关重要的。

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引用次数: 0

Critical defect-driven fatigue evolution mechanism and life prediction of Ti6Al4V part built by laser powder bed fusion 激光粉末床熔合Ti6Al4V零件临界缺陷驱动疲劳演化机理及寿命预测

IF 6.8 2区材料科学 Q1 ENGINEERING, MECHANICAL

International Journal of Fatigue

Pub Date : 2025-12-30 DOI: 10.1016/j.ijfatigue.2025.109476

Jiasen Gu , Deqiao Xie , Xuwen Gu , Shuang Liu , Kai Zhou , Chen Jiao , Rong Jiang , Xinfeng Lv , Juan Hu , Zongjun Tian , Dongsheng Wang , Lida Shen

Fatigue life prediction of laser powder bed fusion (LPBF) components remains challenging because critical defects cannot be reliably identified before service, resulting in large scatter and limited applicability of existing methods. In this study, an integrated framework combining quasi in-situ X-ray computed tomography (XCT), finite element method (FEM), and machine learning (ML) was developed to rapidly screen critical defects and predict fatigue life prior to loading. The results revealed the early-stage evolution of critical defects during crack initiation, and a Murakami-Basquin model was established to quantitatively link defect features with fatigue life. Moreover, the FEM-driven ML approach achieved high-accuracy life prediction within a 1.5× error band, with

σ_{FEM}

identified as the dominant factor, followed by defect depth (

h

) and

\sqrt{area}

, in agreement with classical fatigue criteria. Demonstrated with Ti6Al4V, this work establishes a critical-defect-driven pathway for fatigue life prediction, providing a broadly applicable methodology for defect-sensitive design and life assessment of LPBF components.

激光粉末床熔合（LPBF）部件的疲劳寿命预测仍然具有挑战性，因为在使用前无法可靠地识别关键缺陷，导致现有方法的分散性大，适用性有限。在这项研究中，开发了一个结合准原位x射线计算机断层扫描（XCT）、有限元法（FEM）和机器学习（ML）的集成框架，以快速筛选关键缺陷并在加载前预测疲劳寿命。结果揭示了裂纹萌生过程中关键缺陷的早期演化过程，并建立了Murakami-Basquin模型，定量地将缺陷特征与疲劳寿命联系起来。以σFEM为主导因素，缺陷深度(h)和面积次之，在1.5×误差范围内实现了高精度的寿命预测，符合经典疲劳准则。以Ti6Al4V为例，这项工作建立了一个关键缺陷驱动的疲劳寿命预测路径，为缺陷敏感设计和LPBF部件的寿命评估提供了广泛适用的方法。

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引用次数: 0

Real-Time fatigue crack growth prediction for welded structures based on digital twin framework considering residual stress and variable amplitude loading 考虑残余应力和变幅载荷的焊接结构疲劳裂纹扩展实时预测

IF 6.8 2区材料科学 Q1 ENGINEERING, MECHANICAL

International Journal of Fatigue

Pub Date : 2025-12-30 DOI: 10.1016/j.ijfatigue.2025.109475

Wenyue Zhang , Yong Chen , Xing He , Fang Xue , Peng Xu , Wentao He

This paper proposes a dynamic digital twin framework driven by real-time physical information, which integrates a Radial Basis Function (RBF) neural network and a Dynamic Bayesian Network (DBN). A time-varying fatigue crack growth program is developed to update uncertain crack growth parameters and to enable real-time life prediction under welding residual stress and variable-amplitude loading conditions. A finite element model of welding residual stress is established based on thermo-elastic–plastic theory, and the associated stress intensity factor is calculated using the weight function method. A nonlinear mapping between the stress intensity factor and crack length is constructed using the RBF neural network, accounting for both welding residual stress and variable-amplitude loading. The physics-informed digital twin framework, where the Particle Filter (PF) algorithm drives the DBN, is applied to predict fatigue crack growth and update uncertain parameters in Middle Tension (MT) specimens. Under conditions of periodic multiple overloads, the predicted fatigue life closely matches the experimental results, with an error under 1%. The crack growth process is validated through the co-simulation of ABAQUS and FRANC3D using the updated parameters, with the error between simulated and experimental results remaining below 1%, which demonstrates the high accuracy and robustness of the proposed digital twin framework for fatigue life prediction.

本文提出了一种基于实时物理信息驱动的动态数字孪生框架，该框架将径向基函数（RBF）神经网络和动态贝叶斯网络（DBN）相结合。开发了时变疲劳裂纹扩展程序，以更新不确定裂纹扩展参数，实现焊接残余应力和变幅加载条件下的实时寿命预测。基于热弹塑性理论建立了焊接残余应力有限元模型，采用权函数法计算了相关应力强度因子。在考虑焊接残余应力和变幅加载的情况下，利用RBF神经网络建立了应力强度因子与裂纹长度的非线性映射关系。采用基于物理的数字孪生框架，其中粒子滤波（PF）算法驱动DBN，用于预测中张力（MT）试样的疲劳裂纹扩展和更新不确定参数。在周期性多次过载条件下，预测疲劳寿命与试验结果吻合较好，误差小于1%。利用更新后的参数，通过ABAQUS和FRANC3D联合仿真验证了裂纹扩展过程，仿真结果与实验结果的误差小于1%，验证了所提出的数字孪生框架对疲劳寿命预测的精度和鲁棒性。

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引用次数: 0