Engineering Failure Analysis最新文献_第2页

Failure diagnosis of cooling-water systems using time-sequential fault-tree analysis and gray relational analysis 基于时序故障树分析和灰色关联分析的冷却水系统故障诊断

IF 5.7 2区工程技术 Q1 ENGINEERING, MECHANICAL

Engineering Failure Analysis

Pub Date : 2026-01-10 DOI: 10.1016/j.engfailanal.2026.110537

Jie Zhao, Yun Chen, Xiaoyu Yang, Zhenwei Zhang, Yulei Li

Corrosion-induced leakage in circulating cooling-water systems is governed as much by when as by which factors act. This study aims to develop a sequence-aware diagnostic for leakage assessment by integrating time-sequential fault-tree analysis (TS-FTA) with grey relational analysis (GRA). In TS-FTA, precedence is encoded through minimal cut sequences and an order-critical index; GRA ranks heterogeneous evidence on a common scale. Applied to an industrial pipeline failure, operations/chemistry records with metallography, SEM/EDS, Raman and thermal analysis resolve four mechanism-level intermediate events: oxygen ingress under idle or unstable pressure, selective weld corrosion along weld-centreline ferrite banding/overheated microstructures, inclusion-driven attack, and COD-enabled, MIC-assisted pitting. The model reconstructs time-admissible chains in which oxygen chronology activates weld susceptibility, while inclusion/MIC pathways act as accelerants; the predicted sequences accord with leak mapping and morphologies. The framework provides traceable root-cause verification and a defensible first-to-fix order—stabilise pressurisation/venting and exclude air entry, then assure weld quality, improve material cleanliness, and manage COD/MIC—and is transferable to time-dependent failures in closed-loop water assets.

在循环冷却水系统中，腐蚀引起的泄漏既取决于何时发生，也取决于哪些因素起作用。本研究旨在将时序故障树分析（TS-FTA）与灰色关联分析（GRA）相结合，建立一种序列感知的泄漏诊断方法。在TS-FTA中，优先级通过最小切割序列和顺序关键索引进行编码；GRA在共同尺度上对异质性证据进行排序。应用于工业管道故障，操作/化学记录与金相，SEM/EDS，拉曼和热分析解决了四个机制级的中间事件：在空闲或不稳定压力下的氧气进入，沿焊缝中心铁氧体带的选择性焊缝腐蚀/过热的显微组织，夹杂物驱动的攻击，以及cod激活，mic辅助点蚀。该模型重建了时间允许链，其中氧气年表激活了焊接敏感性，而夹杂物/MIC路径则起到了促进剂的作用；预测序列符合泄漏映射和形态学。该框架提供了可追溯的根本原因验证和可防御的先修复顺序-稳定加压/排气并排除空气进入，然后确保焊接质量，提高材料清洁度，管理COD/ mic -并且可转移到闭环水资产中与时间相关的故障。

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引用次数: 0

Damage decoupled analysis of reinforced concrete slabs subjected to penetration and Explosion: Experimental and numerical investigation 钢筋混凝土板在侵彻和爆炸作用下的损伤解耦分析：实验和数值研究

IF 5.7 2区工程技术 Q1 ENGINEERING, MECHANICAL

Engineering Failure Analysis

Pub Date : 2026-01-10 DOI: 10.1016/j.engfailanal.2026.110564

Tianlong Zhang, Haijun Wu, Heng Dong, Yingqing Lyu, Xin Quan, Fenglei Huang

To address the breaching requirements of reinforced concrete walls, this study analyzes the damage characteristics of reinforced concrete slabs (RCSs) subjected to penetration and explosion. Experiments were conducted using explosion of prefabricated hole and static explosion following penetration. Validated numerical models were employed to investigate the damage mechanisms induced by explosion shock waves and detonation gas. A decoupled approach was used to examine the damage capacities of cylindrical bare charges and the influences of pre-penetration damage on explosive performance. Results indicate that front surface damage primarily resulted from pressure crushing caused by shock waves and detonation gas, while rear surface damage arose from tensile failure due to stress wave reflection, superposition, and the shear plugging of detonation gas. Pre-penetration damage exerted a weakening effect on targets, thereby making cracks easier to form, and rendering cracks to extension during internal explosions. An optimal length-to-diameter ratio of 3.37, with constant charge mass, maximized damage to the RCSs under the studied conditions. Similarly, the highest damage occurred when the charge position-to-target thickness ratio was 0.50. The target dimensionless critical thickness for realizing effective hole expansion was set to 2.73. Perforation diameters after the explosion exhibited linear correlations with the dimensionless impact coefficient. Compared to the penetration at the rebar grid center, that at the midpoint of a single rebar and the intersection of rebars reduced the perforation diameter by 5.7% and 8.9%, respectively. The study offers practical guidance for optimizing charge design and placement, and informing breaching strategies through a deeper understanding of damage mechanisms and rebar configuration effects.

针对钢筋混凝土墙体的突破要求，分析了钢筋混凝土板在侵彻和爆炸作用下的损伤特征。采用预制孔爆破和侵彻后静爆两种方法进行了试验。采用验证的数值模型研究了爆炸冲击波和爆轰气体对结构的损伤机理。采用解耦方法研究了圆柱裸药的损伤能力以及预侵彻损伤对爆炸性能的影响。结果表明：前表面损伤主要由激波和爆震气体造成的压力破碎造成，后表面损伤主要由应力波反射、叠加和爆震气体的剪切堵塞造成的拉伸破坏造成。预侵彻损伤对靶材的削弱作用使裂纹更容易形成，在内爆过程中使裂纹扩展。在恒定电荷质量条件下，最佳长径比为3.37时，对rcs的损伤最大。同样，当装药位置-目标厚度比为0.50时，损伤最大。实现有效扩孔的目标无量纲临界厚度设为2.73。爆炸后射孔直径与无量纲冲击系数呈线性相关。与钢筋网格中心的穿孔相比，单根钢筋中点和钢筋交点的穿孔直径分别减小了5.7%和8.9%。该研究为优化装药设计和布置提供了实践指导，并通过更深入地了解损伤机制和钢筋配置效应，为突破策略提供了指导。

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引用次数: 0

Failure mechanisms and structural response of CIPP-Rehabilitated concrete pipes under external loads 外荷载作用下cip修复混凝土管道破坏机理及结构响应

IF 5.7 2区工程技术 Q1 ENGINEERING, MECHANICAL

Engineering Failure Analysis

Pub Date : 2026-01-09 DOI: 10.1016/j.engfailanal.2026.110563

Jing Liu , Jingguo Cao , Chang Ma , Wenlin Jing , Kangfu Sun , Tingting Yang

Cured-in-place pipe (CIPP) lining is widely used to restore deteriorated concrete drainage pipes; however, the failure evolution and composite load-bearing behavior of rehabilitated pipelines under external loads remain poorly quantified. This study conducted full-scale three-edge bearing tests (TEBT) on intact, corroded, and rehabilitated reinforced concrete pipes (RCPs) to clarify how corrosion defects and liner stiffness jointly influence structural performance. Artificial corrosion was introduced via controlled high-pressure water milling, and two rehabilitation configurations—5 mm semi-structural and 12 mm structural liners—were applied. Circumferential strain responses and crack development were continuously monitored using strain gauges and distributed optical-fiber sensing. Results show that the 12 mm structural liner increased the cracking and ultimate loads by 10–26 %, redistributed strain, and shifted the failure mode from brittle concrete crushing to a ductile composite response with a secondary yield plateau. In contrast, the 5 mm semi-structural liner decreased the ultimate load by up to 17 % due to circumferential stiffness mismatch combined with interface debonding, which prevented effective composite action. Mechanistic analysis reveals that stiffness superposition and neutral-axis migration jointly govern the enhanced bending resistance and ductility of the rehabilitated system. These findings elucidate the external load failure mechanisms of CIPP-reinforced RCPs and provide performance-based guidance for selecting liner stiffness and designing structural rehabilitation strategies for buried pipelines.

现浇管（CIPP）衬砌广泛应用于老化混凝土排水管道的修复；然而，外界荷载作用下修复管道的破坏演化和复合承载行为的量化仍然很差。本研究对完整、腐蚀和修复的钢筋混凝土管道（rcp）进行了全尺寸三缘承载试验（TEBT），以阐明腐蚀缺陷和衬垫刚度如何共同影响结构性能。通过可控高压水磨引入人工腐蚀，采用5 mm半结构衬垫和12 mm结构衬垫两种修复配置。利用应变计和分布式光纤传感技术连续监测了环向应变响应和裂纹发展情况。结果表明：12 mm结构衬垫增加了10 ~ 26%的开裂和极限荷载，使应变重新分布，破坏模式由脆性混凝土破碎转变为具有二次屈服平台的延性复合响应；相比之下，由于周向刚度失配和界面脱粘，5mm半结构衬板将极限载荷降低了17%，从而阻碍了有效的复合作用。力学分析表明，刚度叠加和中性轴偏移共同决定了修复体系抗弯性能和延性的增强。这些研究结果阐明了cipp增强rcp的外载荷破坏机制，为地埋管道衬垫刚度的选择和结构修复策略的设计提供了基于性能的指导。

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引用次数: 0

Failure analysis of utility poles: a review of material deficiencies, environmental effects, structural performance, assessment techniques, and design considerations 电线杆失效分析：回顾材料缺陷、环境影响、结构性能、评估技术和设计考虑

IF 5.7 2区工程技术 Q1 ENGINEERING, MECHANICAL

Engineering Failure Analysis

Pub Date : 2026-01-09 DOI: 10.1016/j.engfailanal.2025.110525

Ahmed I. Elmetwally , El-Sayed Abd-Elaal , Xing Ma , Raufdeen Rameezdeen , Raju Upadhyaya

Utility poles are the backbone of the electricity grid and a key enabler of a carbon–neutral economy, as they connect renewable sources like solar energy to homes and businesses. The number of such utility poles in each country is huge, and so is a significant infrastructure value. In Australia, for example, the current network consists of approximately 7 million utility poles made from wood, concrete, steel, steel–concrete composite, or fibre-reinforced polymer (FRP). While the current grid plans normally do not aim to increase this number of poles, as underground grids are more effective, replacing the current poles with underground assets is cost-prohibitive. So, there is a need to hold these poles in use and continuously replace the aged ones with new, durable poles. This study presents a comprehensive review of failure analysis for different types of poles. The failures can be grouped into three main categories: material-related problems, environmental degradation, and structural response, including cyclic load effects. Understanding these failure categories is important for explaining how poles behave over time and for planning proper maintenance or replacement strategies. It is concluded that future research should prioritise accelerated ageing studies (e.g., the relation between observed degradation and remaining structural capacity). Furthermore, the optimum pole type varies depending on factors such as capital investment, workforce experience, material availability, structural loads, environmental exposure, maintenance demands and associated costs. Lastly, assessment techniques, selection criteria, design considerations and future research directions are outlined.

电线杆是电网的支柱，是碳中和经济的关键推动者，因为它们将太阳能等可再生能源连接到家庭和企业。在每个国家，这样的电线杆的数量都是巨大的，因此具有重要的基础设施价值。例如，在澳大利亚，目前的网络由大约700万个电线杆组成，电线杆由木材、混凝土、钢、钢-混凝土复合材料或纤维增强聚合物（FRP）制成。虽然目前的电网计划通常不打算增加电线杆的数量，因为地下电网更有效，但用地下资产取代现有的电线杆成本过高。因此，有必要保持这些杆子的使用，并不断地用新的、耐用的杆子替换旧的。本文对不同类型电杆的失效分析进行了综述。失效可分为三大类：材料相关问题、环境退化和结构响应，包括循环荷载效应。了解这些故障类别对于解释电线杆随时间的变化以及制定适当的维护或更换策略非常重要。结论是，未来的研究应优先考虑加速老化研究（例如，观察到的退化与剩余结构能力之间的关系）。此外，最佳的电线杆类型取决于资本投资、劳动力经验、材料可用性、结构负载、环境暴露、维护需求和相关成本等因素。最后，对评价技术、选择标准、设计考虑和未来研究方向进行了概述。

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引用次数: 0

Probabilistic failure modeling of seismic-induced misalignment in overhead catenary systems on high-speed railway bridges 高速铁路桥梁接触网系统地震致失中概率破坏模型

IF 5.7 2区工程技术 Q1 ENGINEERING, MECHANICAL

Engineering Failure Analysis

Pub Date : 2026-01-09 DOI: 10.1016/j.engfailanal.2026.110560

Yong-heng Mao , Chang He , Wei Guo , Li-zhong Jiang

Post-earthquake residual misalignment in overhead catenary systems (OCS) installed on high-speed railway bridges can critically impair the power transmission capability of the pantograph-catenary interface, resulting in functional failure of the train’s current collection system. This study investigates the seismic-induced failure mechanism of OCS components from a system-level perspective, focusing on quantifying and predicting residual displacements beyond design tolerances. A physically constrained, data-driven probabilistic modeling framework is proposed to evaluate OCS misalignment under multiple sources of uncertainty, including seismic intensity, bridge damage severity, and structural configuration. To achieve this, a bridge–catenary decoupling modeling strategy is developed to efficiently simulate the transfer of post-earthquake displacement from the bridge to the catenary system across various pier heights and span layouts. The transfer effect is quantitatively described using the first-order Wasserstein distance. A large-scale residual displacement database is constructed, and extreme value distribution fitting reveals that the Gumbel distribution consistently outperforms alternatives across seismic intensity levels. Its parameters are modeled as cubic functions of peak ground acceleration, enabling a Monte Carlo-based kernel density estimation (KDE) to rapidly obtain failure probability distributions. Results show that, in the worst-case configurations, the predicted P95 residual misalignment exceeds the 10 mm functional criterion by more than an order of magnitude. This research provides new insight into the probabilistic failure behavior of catenary systems under seismic excitation and offers a physically interpretable, computationally efficient tool for rapid post-earthquake damage assessment and failure risk ranking in electrified railway infrastructure.

高速铁路桥梁架空接触网系统（OCS）的震后残留失对会严重影响受电弓-接触网界面的输电能力，导致列车电流采集系统的功能失效。本研究从系统层面的角度研究了OCS构件的地震破坏机制，重点是量化和预测超出设计公差的剩余位移。提出了一种物理约束、数据驱动的概率建模框架，用于评估地震烈度、桥梁损伤严重程度和结构配置等多种不确定性来源下的OCS错位。为了实现这一目标，开发了一种桥梁-悬链线解耦建模策略，以有效地模拟震后位移在不同桥墩高度和跨径布置下从桥梁到悬链线系统的传递。用一阶沃瑟斯坦距离定量描述了传递效应。建立了大规模的剩余位移数据库，极值分布拟合表明，在地震烈度水平上，Gumbel分布始终优于替代分布。它的参数被建模为峰值地面加速度的三次函数，使得基于蒙特卡罗的核密度估计（KDE）能够快速获得失效概率分布。结果表明，在最坏情况下，预测的P95残余偏差超过10 mm功能准则一个数量级以上。该研究为地震激励下接触网系统的概率破坏行为提供了新的见解，并为电气化铁路基础设施的地震后快速损伤评估和失效风险排序提供了一个物理上可解释的、计算效率高的工具。

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引用次数: 0

The optimum upgrade in the flexural capacity of heat-damaged one-way RC slabs strengthened with anchored CFRP sheets 锚固碳纤维布加固热损伤单向RC板抗弯承载力的优化提升

IF 5.7 2区工程技术 Q1 ENGINEERING, MECHANICAL

Engineering Failure Analysis

Pub Date : 2026-01-08 DOI: 10.1016/j.engfailanal.2026.110558

Rajai Z. Al-Rousan, Bara’a R. Alnemrawi

This study highlights the effect of strengthening heat-damaged reinforced concrete (RC) slabs with carbon fiber reinforced polymers (CFRP) sheets, which were anchored at their ends to enhance their performance and prevent brittle debonding failure. The efficiency of the anchoring system was examined using a total of twenty-four specimens tested under the effect of different slab depths (60, 80, and 100) mm, temperatures (23, 200, 400, and 600)

^{°}

C, and the CFRF anchoring system (anchored and unanchored). Results show that the structural behavior is significantly improved upon the anchoring, including all its characteristics, and the enhancement extent is directly related to the higher benefit from the CFRP high tensile strength, where the final failure was delayed without premature early debonding or delamination. However, the failure mode, cracking patterns, and the resulting improvement by the CFRP strengthening efficiency mainly depend on the damage level. Increasing the exposure temperature for heat-damaged specimens resulted in increasing the crack-bridging ability provided by the CFRP strengthening material. Finally, results revealed that the efficiency of the anchored CFRP composites increased by 13% to 33% which ends up with improving the strength, ductility, and durability of the heat-damaged RC slabs.

本研究强调了用碳纤维增强聚合物（CFRP）板加固热损伤钢筋混凝土（RC）板的效果，碳纤维增强聚合物（CFRP）板在其末端锚固以提高其性能并防止脆性脱粘破坏。在不同板深（60、80和100）mm、温度（23、200、400和600）°C以及CFRF锚固系统（锚定和非锚定）的影响下，共测试了24个试件，以检验锚固系统的效率。结果表明：锚固后结构性能得到显著改善，包括其所有特性，其改善程度与CFRP高抗拉强度的较高效益直接相关，CFRP高抗拉强度延迟了最终破坏，没有过早的早期脱粘或分层。然而，破坏模式、开裂模式以及碳纤维布加固效率的提高主要取决于损伤程度。提高热损伤试件的暴露温度，CFRP增强材料提供的裂缝弥合能力增强。结果表明，锚固CFRP复合材料的效率提高了13%至33%，最终提高了热损伤RC板的强度、延性和耐久性。

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引用次数: 0

Accelerated failure characterization and reliability analysis of cylindrical electrical connectors under wind vibration environments 风振环境下圆柱形电连接器加速失效特性及可靠性分析

IF 5.7 2区工程技术 Q1 ENGINEERING, MECHANICAL

Engineering Failure Analysis

Pub Date : 2026-01-08 DOI: 10.1016/j.engfailanal.2026.110562

Jinye Wang , Yu Feng , Kai Wu , Shaolei Wu , Wei Wang

Electrical connectors are electrical devices used for branching and connecting conductors in power distribution lines. Under wind loads, they undergo sustained vortex-induced periodic vibrations along with the conductors, causing fatigue and wear at the electrical contact interface and thereby reducing the reliability of electrical connections. This study selected cylindrical electrical connectors as the research subject. A constant-stress accelerated degradation test protocol was designed, employing vibration velocity as the accelerated stress and contact resistance as the performance degradation indicator. By analyzing the contact resistance variation curve and contact interface damage assessment, the failure mechanism of electrical connectors under vibrational environments was revealed, fully accounting for time-varying differences between the specimen and the degradation process. A nonlinear accelerated degradation model incorporating random effects was established, with model parameters solved using an iterative maximum likelihood estimation method. Based on this model, failure probability density curves and reliability curves for electrical connectors were plotted. By evaluating curve variations and extrema, the reliability of electrical connectors was assessed and their service life predicted, providing a robust theoretical foundation for maintenance strategies in power distribution networks.

电连接器是配电线路中用于分支和连接导体的电气装置。在风荷载下，它们与导体一起经历持续的涡激周期性振动，导致电接触界面疲劳和磨损，从而降低了电气连接的可靠性。本研究选择圆柱形电连接器作为研究对象。以振动速度为加速应力，接触阻力为性能退化指标，设计了恒应力加速退化试验方案。通过接触电阻变化曲线分析和接触界面损伤评估，揭示了电连接器在振动环境下的失效机理，充分考虑了试样与降解过程的时变差异。建立了考虑随机效应的非线性加速退化模型，采用迭代极大似然估计法求解模型参数。在此基础上，绘制了电连接器的失效概率密度曲线和可靠性曲线。通过对曲线变化和极值的评估，对电连接器的可靠性进行了评估，并对其寿命进行了预测，为配电网的维护策略提供了有力的理论依据。

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引用次数: 0

A novel event‑driven impact signal model for deep groove ball bearings with inner‑race defects 具有内圈缺陷的深沟球轴承事件驱动冲击信号模型

IF 5.7 2区工程技术 Q1 ENGINEERING, MECHANICAL

Engineering Failure Analysis

Pub Date : 2026-01-08 DOI: 10.1016/j.engfailanal.2026.110559

Jiqiao Li , Zhifeng Shi , Yongqiao Wei , Hua Huang , Changfeng Yan , Xinbin Li , Yajun Xu , Jing Liu

Vibration impact signals are pivotal for quantifying defect sizes in deep groove ball (DGB) bearings. However, conventional dynamic models often produce oversimplified responses that lack the characteristic impulses observed in test signals, primarily because they neglect the nuanced sequence of events during rolling element-defect interactions. To bridge this fidelity gap, this paper proposes a novel event-driven signal model that, based on the inner-race displacement under different bearing load conditions, for the first time deconstructs the rolling element’s passage through an inner-race defect into three distinct physical phases: stress relief, first impact, and second impact. By calculating the time-varying load distribution and contact state transitions associated with each phase, the model synthesizes highly realistic impact impulses without relying on any resonance parameters, setting it apart from existing approaches. The key advantages of this model are its parametric simplicity, computational efficiency, and exceptional phase accuracy, enabling it to faithfully restore the transient impulse train. Experimental validation demonstrates remarkable consistency with test data. Furthermore, the model provides a clear analytical framework to investigate the influence of defect size and rotational speed on each impact event, offering profound insights for precise defect size evaluation and advancing the state-of-the-art in bearing fault simulation.

振动冲击信号是深沟球（DGB）轴承缺陷尺寸量化的关键。然而，传统的动态模型往往产生过于简化的响应，缺乏在测试信号中观察到的特征脉冲，主要是因为它们忽略了滚动元件-缺陷相互作用过程中细微的事件序列。为了弥补这一保真度差距，本文提出了一种新的事件驱动信号模型，该模型基于不同轴承载荷条件下的内圈位移，首次将滚动体通过内圈缺陷的过程分解为三个不同的物理阶段：应力释放、第一次冲击和第二次冲击。通过计算与各相位相关的时变载荷分布和接触状态转换，该模型在不依赖任何共振参数的情况下合成了高度真实的冲击脉冲，与现有方法不同。该模型的主要优点是参数简单，计算效率高，相位精度高，能够忠实地恢复瞬态脉冲序列。实验验证与试验数据具有显著的一致性。此外，该模型提供了一个清晰的分析框架来研究缺陷尺寸和转速对每个冲击事件的影响，为精确评估缺陷尺寸提供了深刻的见解，并推动了轴承故障模拟的最新发展。

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引用次数: 0

Effect of perforated friction block design on the tribological behavior of high-speed train brake interfaces under different ambient temperatures 不同环境温度下，穿孔摩擦块设计对高速列车制动界面摩擦学性能的影响

IF 5.7 2区工程技术 Q1 ENGINEERING, MECHANICAL

Engineering Failure Analysis

Pub Date : 2026-01-08 DOI: 10.1016/j.engfailanal.2026.110555

Qixiang Zhang , Zhou Yu , Meng Wu , Xiaocui Wang , Jiliang Mo

To elucidate the influence of the perforation structure on the tribological characteristics of high-speed train brake interfaces, solid (ST) and perforated (PT) triangular friction blocks were investigated under room (20 °C) and low (−20 °C) temperatures. By combining braking bench tests with a temperature-displacement-wear coupled finite element (FE) model, the synergistic effects of ambient temperature and friction block geometry were systematically analyzed. Results show that low temperatures significantly increase the hardness and brittleness of the friction material, leading to severe abrasive wear and intensified high-frequency noise. However, the perforated design is found to effectively regulate interfacial behavior by improving contact stress distribution and facilitating debris removal. This structure mitigates the uneven wear and vibration instabilities typically exacerbated by cold environments. This study reveals the synergistic mechanism by which ambient temperature and perforation geometry regulate braking tribological behavior, providing theoretical support for structural optimization and reliable operation of high-speed train brake systems in complex environments.

为了阐明穿孔结构对高速列车制动界面摩擦学特性的影响，在室温（20°C）和低温（- 20°C）下研究了固体（ST）和穿孔（PT）三角形摩擦块。通过将制动台架试验与温度-位移-磨损耦合有限元模型相结合，系统分析了环境温度与摩擦块几何形状的协同效应。结果表明：低温显著提高了摩擦材料的硬度和脆性，导致磨粒磨损严重，高频噪声加剧；然而，研究发现，通过改善接触应力分布和促进碎屑清除，穿孔设计有效地调节了界面行为。这种结构减轻了通常在寒冷环境下加剧的不均匀磨损和振动不稳定。研究揭示了环境温度和孔眼几何形状对制动摩擦学行为的协同调节机制，为复杂环境下高速列车制动系统的结构优化和可靠运行提供了理论支持。

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引用次数: 0

Microstructural degradation and creep damage of T91 steel: a case study of fish-mouth rupture in heat recovery steam generator superheater tubes T91钢的显微组织退化与蠕变损伤——以热回收蒸汽发生器过热器管鱼口断裂为例

IF 5.7 2区工程技术 Q1 ENGINEERING, MECHANICAL

Engineering Failure Analysis

Pub Date : 2026-01-07 DOI: 10.1016/j.engfailanal.2026.110554

Atef Zekri , Jonas Da Silva De Sa , Akshath Raghu Shetty , Kamal Mroue , Abdelmajid Salhi , Brahim Aissa , Said Mansour

This study offers a multi-scale investigation into the creep rupture of a Grade T91 Cr-Mo steel superheater tube from a Heat Recovery Steam Generator (HRSG) that experienced a catastrophic fish-mouth fracture after prolonged service. Unlike conventional case studies that rely on a single analytical technique, this research combines optical microscopy, scanning electron microscopy (SEM/EDS), atomic force microscopy (AFM), X-ray diffraction (XRD), and hardness profiling on the same failed component. This method allows a direct link between nanoscale features and large-scale fracture behaviour. Findings reveal progressive carbide spheroidization, boundary segregation of (Cr, Mo)-rich precipitates, and intergranular void formation, along with oxide scale thickening that led to increased localised overheating. These observations are consistent with established tertiary-creep degradation mechanisms reported for T91 steels. AFM analysis was used to characterise surface topography and grain-boundary relief associated with creep damage, complementing conventional microscopy techniques. The combined hardness reduction and phase analysis confirms tertiary creep rupture as the primary failure mode, aggravated by internal oxidation and localised wall thinning. Key features of this failure include a pronounced fish-mouth rupture geometry, of sulphur and chlorine detected on the steam-side surface, and the comparative chemistry of inner and outer oxide scales. This comprehensive approach not only clarifies the combined effects of creep and oxidation in T91 failures but also underscores the diagnostic value of integrating nanoscale AFM with traditional metallurgical techniques for service-life prediction and failure prevention in high-temperature power plant components.

本研究对热回收蒸汽发生器（HRSG）的T91级Cr-Mo钢过热器管进行了多尺度蠕变断裂研究，该过热器管在长期使用后发生了灾难性的鱼嘴断裂。与依赖单一分析技术的传统案例研究不同，该研究结合了光学显微镜、扫描电子显微镜（SEM/EDS）、原子力显微镜（AFM）、x射线衍射（XRD）和硬度分析对同一失效部件进行分析。这种方法可以将纳米尺度特征与大规模断裂行为直接联系起来。结果表明，碳化物球化、富（Cr, Mo）析出相边界偏析、晶间空洞形成，以及氧化层增厚导致局部过热加剧。这些观察结果与T91钢的三级蠕变降解机制一致。AFM分析用于表征与蠕变损伤相关的表面形貌和晶界起伏，补充了传统的显微镜技术。硬度降低和相分析证实三级蠕变破裂是主要的破坏模式，内部氧化和局部壁薄加剧了破坏模式。该故障的主要特征包括明显的鱼嘴破裂几何形状，在蒸汽侧表面检测到硫和氯，以及内部和外部氧化物鳞片的比较化学性质。这一综合方法不仅阐明了蠕变和氧化对T91失效的综合影响，而且强调了将纳米尺度原子力显微镜与传统冶金技术相结合，在高温电厂部件的使用寿命预测和失效预防方面的诊断价值。

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