International Journal of Fatigue最新文献_第5页

Effect of distinct ferrite structures on the crack propagation behavior in a Si-enriched ferritic/martensitic (F/M) steel under low-cycle fatigue (LCF) at 600 ℃ 不同铁素体组织对富si铁素体/马氏体（F/M）钢600℃低周疲劳裂纹扩展行为的影响

IF 6.8 2区材料科学 Q1 ENGINEERING, MECHANICAL

International Journal of Fatigue

Pub Date : 2026-06-01 Epub Date: 2026-01-20 DOI: 10.1016/j.ijfatigue.2026.109517

Jun Zhang , Xiaoxin Zhang , Hao Ren , Decang Zhang , Yingxue Chen , Feifei Zhang , Xinhao Zhang , Qingzhi Yan

Advanced power plants demand steels with enhanced high-temperature low-cycle fatigue (LCF) performance. However, the insufficient understanding of ferrite’s role in crack propagation limits both optimization design and application of the novel Si-enriched ferritic/martensitic (F/M) steels. Hence, the crack propagation behavior during LCF was investigated in steels with varied ferrite structures obtained through two distinct treatments: normalizing & tempering process (NT) and hot rolling & tempering process (HR). The ferrite for NT is “clearer” with few and large sub-grains, whereas, for HR, the ferrite contains high density of small sub-grains. These sub-grains with slightly different orientation effectively deflect the crack propagation path. Moreover, hot rolling produced a pronounced texture characterized by a large misorientation between the crack plane and the {100} cleavage plane, thereby increasing the energy required for crack propagation. The sub-grain structure together with the strong texture indicates a higher resistance to crack propagation for HR. However, the notably higher ferrite fraction for HR results in a lower fatigue life, as the suboptimal strength ultimately leads to a premature onset of stage III with sharply decreasing stress, which limits the period of stable crack propagation, thereby, inducing an early failure. This excessive ferrite was formed due to the temperature drop during hot rolling, which shifted the calculated equilibrium ferrite from <5 % to nearly 45 %. Overall, these results highlight the importance of ferrite refinement and fraction control in optimizing the fatigue resistance of Si-enriched F/M steels. Guided by this insight, potential processing strategies are proposed for future optimization.

先进的电厂要求钢具有增强的高温低周疲劳性能。然而，对铁素体在裂纹扩展中的作用认识不足，限制了新型富硅铁素体/马氏体（F/M）钢的优化设计和应用。因此，通过正火回火（NT）和热轧回火（HR）两种不同的处理方法，研究了不同铁素体组织的钢在LCF过程中的裂纹扩展行为。NT的铁素体“更清晰”，亚晶粒少而大，而HR的铁素体则含有高密度的小亚晶粒。这些取向稍有不同的亚晶有效地偏转了裂纹扩展路径。此外，热轧产生了明显的织构，其特征是裂纹面与{100}解理面之间存在较大的错向，从而增加了裂纹扩展所需的能量。亚晶组织和强织构表明，HR具有较高的抗裂纹扩展能力。然而，较高的铁素体分数会导致较低的疲劳寿命，因为次优强度最终会导致III阶段过早开始，应力急剧下降，从而限制了稳定裂纹扩展的时间，从而导致早期失效。这种过量的铁素体是由于热轧过程中的温度下降而形成的，它使计算的平衡铁素体从<； 5%移动到近45%。总之，这些结果突出了铁素体细化和分数控制对优化富硅F/M钢的抗疲劳性能的重要性。在这一见解的指导下，提出了未来优化的潜在处理策略。

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引用次数: 0

Effects of chloride ion concentration on the LCF performance of 316L austenitic stainless steel in high-temperature pressurized water 氯离子浓度对316l奥氏体不锈钢高温加压水中LCF性能的影响

IF 6.8 2区材料科学 Q1 ENGINEERING, MECHANICAL

International Journal of Fatigue

Pub Date : 2026-06-01 Epub Date: 2026-01-15 DOI: 10.1016/j.ijfatigue.2026.109490

Shizhuang Liu , Hongjun Yu , Shihan Man , Xun Zhang , Yaode Yin , Xiaoming Bai , Ziheng Tang , Licheng Guo

This investigation examines the influence of the chloride ion concentrations (0.05%–5%) on the low-cycle fatigue (LCF) behavior of 316L austenitic stainless steel (316L SS) under high-temperature pressurized water (HTPW) conditions. Experimental results indicate that chloride ions substantially decrease fatigue life, with maximum reductions reaching ∼55% relative to pure water conditions. To enable quantitative fatigue life assessment, a progressive modeling approach is developed and validated. Initially, the strain amplitude effect is incorporated into the environmental fatigue correction factor under pure water conditions. Building on this foundation, the effect of chloride ion concentration is introduced to establish a logarithmic predictive model that demonstrates accuracy across the 0.05%–5% range. Validation experiments at intermediate concentrations (0.3% and 3%) yield prediction errors within 10%. Analysis of the cyclic stress response (CSR) reveals that chloride addition shortens the peak stress saturation stage and accelerates stress degradation. Fractographic examination reveals that increasing chloride concentration accelerates fatigue degradation mechanisms, characterized by expanded fatigue striation spacing and increased oxide particle coarsening. These findings advance the mechanistic understanding of chloride-mediated corrosion fatigue. Overall, a logarithmic predictive model is proposed to predict the fatigue life of 316L SS in chloride-containing HTPW environments, with improved predictive accuracy for the 316L SS.

本文研究了氯离子浓度（0.05% ~ 5%）对316L奥氏体不锈钢（316L SS）在高温加压水（HTPW）条件下低周疲劳（LCF）行为的影响。实验结果表明，氯离子大大降低了疲劳寿命，与纯水条件相比，最大降幅可达55%。为了实现疲劳寿命的定量评估，开发并验证了一种渐进式建模方法。在纯水条件下，将应变幅值效应纳入环境疲劳修正系数。在此基础上，引入氯离子浓度的影响，建立了精度在0.05% ~ 5%范围内的对数预测模型。验证实验在中间浓度（0.3%和3%）下的产率预测误差在10%以内。循环应力响应分析表明，氯化物的加入缩短了峰值应力饱和阶段，加速了应力降解。断口分析表明，氯离子浓度的增加加速了疲劳降解机制，表现为疲劳条纹间距的扩大和氧化物颗粒粗化的增加。这些发现促进了对氯化物介导的腐蚀疲劳机理的理解。总体而言，提出了一种对数预测模型来预测316L SS在含氯化物HTPW环境中的疲劳寿命，提高了316L SS的预测精度。

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引用次数: 0

A 2.9 GPa modified M50 steel with Remarkably high fatigue strength by Nb and Al alloying 采用Nb和Al合金化改性了一种GPa为2.9的M50钢，具有很高的疲劳强度

IF 6.8 2区材料科学 Q1 ENGINEERING, MECHANICAL

International Journal of Fatigue

Pub Date : 2026-06-01 Epub Date: 2026-01-27 DOI: 10.1016/j.ijfatigue.2026.109518

Jing Zhang , Qingfeng Kang , Hui Wang , Zexi Zhang , Wenquan Cao

Coarse prior austenite grains and large primary carbides are the main reasons for the limited strength and poor fatigue performance of M50 steel. In this study, the addition of Nb and Al to M50 steel was designed, leading to the simultaneous refinement of both the prior austenite grains (to 8.55 ± 0.58 μm) and the largest primary carbides (to 20 μm). Furthermore, the modified steel exhibited extremely excellent tensile strength (R_m: 2864 ± 49 MPa and R_p0.2: 2502 ± 22 MPa) and rotating bending fatigue strength (R_-1 = 1153 MPa). Microstructural characterization further revealed that alloying with Nb and Al synergistically altered the precipitation sequence during tempering, which suppressed Fe₃C precipitation and spheroidization, and instead promoted the formation of a dense and uniform distribution of nanoscale M₂C carbides, thereby significantly enhancing the tensile strength. Additionally, the Nb and Al alloying refined the primary MC and M₂C carbides by inhibiting eutectic reactions and promoting the high-temperature decomposition of eutectic carbides. Consequently, this pronounced carbide refinement shifted fatigue crack initiation away from the carbide-dominated fracture sites (typical of conventional M50 steel) to weak microstructural regions within the modified steel’s matrix, thereby markedly increasing fatigue strength. These weak structures were associated with local chemical inhomogeneities and strain concentration at martensite packets and blocks boundaries. In summary, this systematic investigation into the effects of Nb and Al alloying on the microstructure evolution, mechanical properties, and fatigue behavior of M50 steel offers a promising strategy for developing high-temperature bearing steels with ultrahigh strength and excellent fatigue performance.

粗的奥氏体晶粒和大的初生碳化物是造成M50钢强度有限、疲劳性能差的主要原因。在本研究中，设计了在M50钢中添加Nb和Al的方法，使先前的奥氏体晶粒（细化到8.55 ± 0.58 μm）和最大的初生碳化物（细化到20 μm）同时细化。此外,修改后的钢表现出非常优秀的抗拉强度(Rm: 2864 ± 49 MPa和Rp0.2: 2502 ± 22 MPa)和旋转弯曲疲劳强度(r 1 = 1153 MPa)。显微组织表征进一步表明，Nb和Al的合金化协同改变了回火过程中的析出顺序，抑制了Fe3C的析出和球化，促进了致密均匀分布的纳米级M2C碳化物的形成，从而显著提高了抗拉强度。Nb和Al合金通过抑制共晶反应和促进共晶碳化物的高温分解来细化初生MC和M2C碳化物。因此，这种明显的碳化物细化将疲劳裂纹的起裂点从碳化物主导的断裂部位（典型的传统M50钢）转移到改性钢基体内的弱显微组织区域，从而显著提高了疲劳强度。这些弱结构与局部化学不均匀性和马氏体包和块边界的应变浓度有关。综上所述，本文系统研究了Nb和Al合金对M50钢组织演变、力学性能和疲劳行为的影响，为开发具有超高强度和优异疲劳性能的高温轴承钢提供了有希望的策略。

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引用次数: 0

Competing role of volumetric defects and microstructure on the fatigue behavior of additively manufactured Inconel 718: An experimental study 体积缺陷和微观组织对增材制造Inconel 718疲劳性能影响的实验研究

IF 6.8 2区材料科学 Q1 ENGINEERING, MECHANICAL

International Journal of Fatigue

Pub Date : 2026-06-01 Epub Date: 2026-01-10 DOI: 10.1016/j.ijfatigue.2026.109486

Indrajit Nandi , Sajith Soman , Reza Molaei , Will Tilson , Nima Shamsaei , Shuai Shao

This study investigates the competing role of volumetric defects and microstructure on the fatigue behavior of additively manufactured Inconel 718 (IN718), with emphasis on the crack initiation mechanism. IN718 rods were fabricated using laser powder bed fusion with tuned process parameters and heat treatments to obtain diverse defect contents and microstructures. Both uniaxial tensile and fully-reversed, force-controlled fatigue tests were performed, and fractography was conducted to analyze various features observed at fatigue crack initiation sites. The influence of defects and microstructure was more pronounced on fatigue behavior than on tensile behavior. Both microstructure- and defect-mediated fatigue crack initiations were observed. For the former, facets were observed at the crack initiation sites which were due to the formation and operation of persistent slip bands. Interestingly, results revealed a similar dependence of fatigue life on the feature size at the crack initiation sites, regardless of the crack initiation mechanism.

本文研究了体积缺陷和微观组织对增材制造IN718疲劳性能的影响，重点研究了裂纹的起裂机理。通过调整工艺参数和热处理，采用激光粉末床熔合法制备了不同缺陷含量和显微组织的IN718棒。进行了单轴拉伸和完全反向力控制疲劳试验，并进行了断口分析，分析了疲劳裂纹萌生部位的各种特征。缺陷和显微组织对疲劳性能的影响大于对拉伸性能的影响。观察到微观组织和缺陷介导的疲劳裂纹萌生。对于前者，在裂纹起裂部位观察到由于持续滑移带的形成和作用而产生的切面。有趣的是，结果显示，无论裂纹起裂机制如何，疲劳寿命与裂纹起裂部位的特征尺寸有相似的依赖关系。

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引用次数: 0

Microstructural origins for the simultaneously enhanced high-cycle fatigue performance and fatigue crack growth resistance of a carbide-free bainite steel 无碳化物贝氏体钢同时提高高周疲劳性能和抗疲劳裂纹扩展性能的组织根源

IF 6.8 2区材料科学 Q1 ENGINEERING, MECHANICAL

International Journal of Fatigue

Pub Date : 2026-06-01 Epub Date: 2026-01-22 DOI: 10.1016/j.ijfatigue.2026.109513

Tianyu Zhang , Yu Wang , Zhanqing Yin , Xiaoming Liu , Chenchong Wang , Lingyu Wang , Chi Zhang , Wei Xu

Carbide-free bainite (CFB) steel, consisting of bainitic laths and metastable retained austenite (RA), offers excellent static properties and fatigue resistance, making it a potential replacement for conventional axle steels. However, the relationships among its microstructure, fatigue life under various stresses, and fatigue crack growth (FCG) behavior remain unclear. This study designed two CFB axle steels, AT350 and AT300, by austempering at 350 °C or 300 °C followed by low-temperature tempering, producing different bainitic lath sizes and RA stabilities. Their mechanical properties, high-cycle fatigue (HCF) performance, and FCG behavior were systematically investigated. The AT300 sample featured finer bainite laths (average thickness: 231 nm) and higher RA stability than that of the AT350 sample, due to prior austenite grain segmentation by primary martensite. Consequently, AT300 achieved higher tensile strength (1575 MPa) and HCF strength (760 MPa, fatigue limit at 10⁷ cycles). Under low-stress fatigue, the AT300 sample exhibited longer life and slower crack growth than the AT350 sample. Under high-stress fatigue, however, the fatigue lives of the AT350 and AT300 samples were nearly equivalent, as AT350′s greater ductility and secondary cracking compensated for its lower strength. In the FCG regime, AT300 showed a wider resistance plateau and a lower Paris exponent, indicating superior crack growth resistance. This enhancement arises from fine bainitic laths deflecting cracks and stable RA reducing martensitic transformation at the crack tip, thereby avoiding brittle martensite channels and absorbing strain energy. These findings provide valuable theoretical and experimental guidance for designing axle steels with superior fatigue resistance.

无碳化物贝氏体（CFB）钢由贝氏体板条和亚稳残余奥氏体（RA）组成，具有优异的静态性能和抗疲劳性能，是传统车轴钢的潜在替代品。然而，其显微组织、不同应力下的疲劳寿命和疲劳裂纹扩展（FCG）行为之间的关系尚不清楚。本研究设计了两种循环流化床车轴钢AT350和AT300，分别在350°C和300°C等温回火，然后再进行低温回火，产生了不同的贝氏体板条尺寸和RA稳定性。系统地研究了它们的力学性能、高周疲劳（HCF）性能和FCG行为。与AT350相比，AT300样品具有更细的贝氏体板条（平均厚度为231 nm）和更高的RA稳定性，这是由于初生马氏体对奥氏体晶粒进行了预先分割。因此，AT300获得了更高的抗拉强度（1575 MPa）和HCF强度（760 MPa， 107次循环的疲劳极限）。在低应力疲劳下，AT300试样比AT350试样具有更长的寿命和更慢的裂纹扩展。然而，在高应力疲劳下，AT350和AT300样品的疲劳寿命几乎相等，因为AT350的高延展性和二次开裂弥补了其较低的强度。在FCG状态下，AT300表现出更宽的阻力平台和更低的Paris指数，表明其具有更强的抗裂纹扩展能力。这种增强是由于细小的贝氏体板条偏转裂纹和稳定的RA减少了裂纹尖端的马氏体转变，从而避免了脆性马氏体通道并吸收了应变能。这些研究结果为设计具有优良抗疲劳性能的车轴钢提供了有价值的理论和实验指导。

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引用次数: 0

Low-cycle fatigue performance and porosity evolution in spray-formed 7055 Al-alloy 喷射成形7055铝合金的低周疲劳性能及孔隙率演变

IF 6.8 2区材料科学 Q1 ENGINEERING, MECHANICAL

International Journal of Fatigue

Pub Date : 2026-06-01 Epub Date: 2026-01-22 DOI: 10.1016/j.ijfatigue.2026.109514

Weichang Wei , Chenyang Zhang , Yapeng Huang , Xia He , Yong Zhang , Guang Li , Yanjin Xu , Baoshuai Han , Cai Hu , Lingying Ye

The effects of pore characteristics and evolution on the fatigue performance of spray-formed 7055 aluminum alloy were investigated using synchrotron X-ray computed tomography (CT), electron backscatter diffraction (EBSD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The results demonstrate that pore characteristics and their evolution during cyclic loading directly govern the fatigue performance. As the extrusion ratio increased from 7 to 48, the size and number density of pores decreased significantly, which was accompanied by a progressive improvement in low-cycle fatigue life. During fatigue cycling, severe local plastic deformation occurred around pores sized 10–20 μm, causing substantial pore growth and promoting rapid crack initiation. For pores sized 5–10 μm, the local plastic deformation was less pronounced, resulting in delayed crack initiation and extended fatigue life. Pores smaller than 5 μm underwent negligible plastic deformation and thus had a minimal impact on fatigue performance. Moreover, pores accelerated fatigue crack propagation by providing preferential paths for rapid crack growth.

采用同步x射线计算机断层扫描（CT）、电子背散射衍射（EBSD）、扫描电子显微镜（SEM）和透射电子显微镜（TEM）研究了孔隙特征及其演化对喷射成形7055铝合金疲劳性能的影响。结果表明，孔隙特征及其在循环加载过程中的演变直接决定了材料的疲劳性能。随着挤压比从7增加到48，孔隙尺寸和数量密度显著减小，低周疲劳寿命逐步提高。在疲劳循环过程中，孔径为10 ~ 20 μm的孔隙周围发生了严重的局部塑性变形，孔隙扩展迅速，裂纹萌生迅速。当孔隙尺寸为5 ~ 10 μm时，局部塑性变形不明显，裂纹起裂延迟，疲劳寿命延长。小于5 μm的孔隙塑性变形可以忽略不计，因此对疲劳性能的影响最小。此外，孔隙通过为裂纹快速扩展提供优先路径来加速疲劳裂纹扩展。

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引用次数: 0

Bayesian model updating and model validation for fatigue life prediction of additively manufactured aluminum alloys 增材制造铝合金疲劳寿命预测的贝叶斯模型更新与模型验证

IF 6.8 2区材料科学 Q1 ENGINEERING, MECHANICAL

International Journal of Fatigue

Pub Date : 2026-06-01 Epub Date: 2026-01-23 DOI: 10.1016/j.ijfatigue.2026.109501

Zhanhua Liang , Jingwen Song , Feifan Li , Xianmin Chen , Jihong Zhu , Weihong Zhang

Fatigue life prediction for additively manufactured aluminum alloys is challenging due to limited data and significant material scatter. To address this, this study proposes a Bayesian uncertainty quantification framework for probabilistic prediction and model selection. Fatigue experiments were conducted on Laser Powder Bed Fusion (LPBF) AlSi10Mg specimens under two build directions. Bayesian inference was employed to update the parameters of four candidate models, characterizing data scarcity in the form of prediction uncertainty. U-pooling and Model Evidence metrics were then utilized to quantitatively evaluate model performance. The proposed framework effectively generated 95% confidence intervals that encapsulate most of the experimental data. Results indicate that specimens loaded perpendicular to the build direction (H-direction) exhibit superior fatigue resistance compared to those loaded parallel to it (S-direction). Quantitative validation identifies the Smith-Watson-Topper model and the Morrow model as the optimal predictors for the two directions. This work provides a reliable tool for fatigue assessment under data-scarce conditions.

由于数据有限和材料分散严重，增材制造铝合金的疲劳寿命预测具有挑战性。为了解决这个问题，本研究提出了一个用于概率预测和模型选择的贝叶斯不确定性量化框架。对激光粉末床熔合（LPBF） AlSi10Mg试样在两种构建方向下进行了疲劳试验。采用贝叶斯推理更新四个候选模型的参数，以预测不确定性的形式表征数据稀缺性。然后使用u池和模型证据度量来定量评估模型性能。提出的框架有效地生成了95%的置信区间，封装了大多数实验数据。结果表明，竖向加载（h方向）比平行加载（s方向）具有更好的抗疲劳性能。定量验证表明Smith-Watson-Topper模型和Morrow模型是两个方向的最佳预测因子。这项工作为数据稀缺条件下的疲劳评估提供了可靠的工具。

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引用次数: 0

Enhancing fatigue life of L12-strengthened multi-principal element alloy by tailoring grain boundary characteristics and precipitation 通过调整晶界特征和析出来提高l12强化多主元素合金的疲劳寿命

IF 6.8 2区材料科学 Q1 ENGINEERING, MECHANICAL

International Journal of Fatigue

Pub Date : 2026-06-01 Epub Date: 2026-01-30 DOI: 10.1016/j.ijfatigue.2026.109523

Shaoxin Cai , Jingping Cui , Baijun Yang , Dong Han , Jianqiang Wang

A significant challenge has recently been highlighted in L1₂-strengthened multi-principal element alloys (MPEAs), where the Al-Ti-bearing systems are prone to forming the coarse-sized discontinuous precipitates (DPs) along grain boundaries (GBs) during aging. This intensifies the strain localization near GBs, thus posing a potential threat to the fatigue performance of the alloy, as reported in traditional alloys. To address this, the grain boundary engineering (GBE) strategy was applied to a (NiCoCr)₉₄Al₃Ti₃ MPEA through simple thermomechanical treatment, and its influence on DPs and the resulting tension–tension fatigue behavior was systematically examined. The results reveal that GBE treatment can significantly increase the fraction of special boundaries dominated by Σ3 boundaries and disrupt the connectivity of random high-angle grain boundaries, thereby effectively inhibiting the formation of DPs. Such a microstructure optimization leads to a 2–4 times improvement in the fatigue life, depending on the stress amplitudes. The enhanced properties are attributed to the synergistic role of modified GB characteristics and DP suppression. This effect promotes the deformation uniformity and alleviates the strain incompatibility between the two sides of boundaries, thus enhancing crack initiation and propagation resistance. Our work provides a simple yet effective pathway for improving the fatigue performance of L1₂-strengthened MPEAs, particularly under high-stress amplitudes where GB cracking is the dominant failure mode.

l12强化多主元素合金（MPEAs）在时效过程中容易沿晶界（GBs）形成粗尺寸的不连续相（DPs）。这加剧了GBs附近的应变局部化，从而对合金的疲劳性能构成了潜在的威胁，正如传统合金所报道的那样。为了解决这一问题，通过简单的热处理将晶界工程（GBE）策略应用于（NiCoCr）94Al3Ti3 MPEA，并系统地研究了其对DPs和由此产生的拉伸-拉伸疲劳行为的影响。结果表明，GBE处理可以显著增加Σ3晶界主导的特殊晶界的比例，破坏随机高角度晶界的连性，从而有效抑制DPs的形成。这种微观结构优化导致疲劳寿命提高2-4倍，具体取决于应力幅值。性能的增强是由于改性的GB特性和DP抑制的协同作用。这种作用促进了变形均匀性，缓解了边界两侧的应变不相容，从而增强了裂纹起裂和扩展的阻力。我们的工作为提高l12强化mpea的疲劳性能提供了一个简单而有效的途径，特别是在高应力幅下，GB裂纹是主要的破坏模式。

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引用次数: 0

An energy-based physics–data fusion model for thermomechanical fatigue life prediction of directionally solidified superalloys 基于能量的定向凝固高温合金热-机械疲劳寿命预测物理-数据融合模型

IF 6.8 2区材料科学 Q1 ENGINEERING, MECHANICAL

International Journal of Fatigue

Pub Date : 2026-06-01 Epub Date: 2026-01-25 DOI: 10.1016/j.ijfatigue.2026.109521

Jundong Wang , Yuanmin Tu , Song Wu , Pengfei He , Zhixun Wen

This study investigates the thermomechanical fatigue (TMF) behaviour and life prediction of directionally solidified nickel-based superalloys under different mechanical stress levels. TMF tests were first performed to obtain cyclic stress–strain responses and fatigue lives, and the associated fracture surfaces and microstructural evolution were characterised to identify the dominant damage and failure mechanisms at different stages. On this basis, a thermo-mechanically coupled TMF constitutive model incorporating anisotropic yielding and damage evolution was established. The classical Zamrik energy model was subsequently modified by embedding a nonlinear damage evolution law into the energy framework, introducing the viscoplastic energy dissipated per cycle as the driving variable, and explicitly accounting for the effects of phase angle and temperature, thereby yielding an energy-based TMF life-prediction relation. In parallel, a Transformer–LSTM network was constructed to learn a nonlinear mapping from multivariate time-series data to life-related features. Building on these developments, an energy-driven physics–data fusion life-prediction approach was proposed, in which the energy parameter predicted by the data-driven model is supplied to the modified Zamrik model for TMF life assessment. The results show that, under various loading conditions, most lives predicted by the fusion model fall within a two-fold dispersion band about the experimental data, with a generally conservative bias. The proposed approach combines high prediction accuracy with clear physical interpretability and provides a promising tool for TMF life evaluation and engineering design of nickel-based superalloy components.

研究了定向凝固镍基高温合金在不同机械应力水平下的热疲劳行为和寿命预测。首先进行TMF试验以获得循环应力-应变响应和疲劳寿命，并对相关断口表面和微观组织演变进行表征，以确定不同阶段的主要损伤和破坏机制。在此基础上，建立了考虑各向异性屈服和损伤演化的热-力耦合TMF本构模型。随后，对经典的Zamrik能量模型进行修正，将非线性损伤演化规律嵌入能量框架，引入每循环耗散的粘塑性能量作为驱动变量，并明确考虑相角和温度的影响，从而得到基于能量的TMF寿命预测关系。同时，构建了Transformer-LSTM网络，学习多变量时间序列数据到生命相关特征的非线性映射。在此基础上，提出了一种能量驱动的物理-数据融合寿命预测方法，将数据驱动模型预测的能量参数提供给改进的Zamrik模型，用于TMF寿命评估。结果表明，在不同的载荷条件下，核聚变模型预测的寿命与实验数据在两倍频散范围内，具有普遍的保守偏差。该方法具有较高的预测精度和清晰的物理可解释性，为镍基高温合金部件的TMF寿命评估和工程设计提供了一种有前景的工具。

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引用次数: 0

The effects of austempering time on mechanical properties of the novel GCr15Si1MoNbV bearing steel and on its rolling contact fatigue behaviors 等温回火时间对新型GCr15Si1MoNbV轴承钢力学性能及滚动接触疲劳行为的影响

IF 6.8 2区材料科学 Q1 ENGINEERING, MECHANICAL

International Journal of Fatigue

Pub Date : 2026-06-01 Epub Date: 2026-01-28 DOI: 10.1016/j.ijfatigue.2026.109519

Yanhui Wang , Ziqi Liu , Xubiao Wang , Xiang Chen , Xiliang Zhang , Wenfei Shen , Qian Yang , Leijie Zhao , Zhinan Yang

Rolling contact fatigue (RCF) is a critical failure mode of bearings. In this study, the novel GCr15Si1MoNbV bearing steel was subjected to low-temperature salt-bath austempering, and the effects of phase transformation during austempering on microstructure, mechanical properties and RCF behavior were investigated experimentally using scanning electron microscopy (SEM), transmission electron microscopy (TEM), electron backscatter diffraction (EBSD), and RCF testing. The specimen austempered at 190 °C for 10 h with a multiphase microstructure composed of nanobainite, martensite, and a high volume fraction of retained austenite exhibited exceptional performance. This kind of multiphase microstructure provided high surface hardness, excellent impact toughness, and a favorable residual stress gradient characterized by compressive stress at surface and tensile stress at subsurface, which collectively delayed crack initiation and propagation. As a result, the basic rating life (L₁₀), the median life (L₅₀), and the characteristic life (V_s) of the martensite–nanobainite–austenite 10 h specimen were 2–3 times to those of the martensite-dominated 2 h specimen, and 3–5 times to those of the nanobainite-dominated 48 h specimen. These findings indicate that the synergistic optimization of multiphase microstructure and residual stress gradient is the key mechanism for enhancing the RCF performance of bearing steels.

滚动接触疲劳（RCF）是轴承的一种关键失效模式。对新型GCr15Si1MoNbV轴承钢进行低温盐浴等温回火，利用扫描电镜（SEM）、透射电镜（TEM）、电子背散射衍射（EBSD）和RCF测试，研究了等温回火过程中相变对钢组织、力学性能和RCF行为的影响。样品在190℃下等温10 h，形成由纳米贝氏体、马氏体和大量残余奥氏体组成的多相组织，表现出优异的性能。这种多相组织具有高的表面硬度、优异的冲击韧性和良好的残余应力梯度，其特征为表面压应力和亚表面拉应力，共同延缓了裂纹的萌生和扩展。结果表明，马氏体-纳米贝氏体-奥氏体10 h试样的基本额定寿命（L10）、中位寿命（L50）和特征寿命（Vs）分别是马氏体为主的2 h试样的2 ~ 3倍、纳米贝氏体为主的48 h试样的3 ~ 5倍。研究结果表明，多相组织和残余应力梯度的协同优化是提高轴承钢RCF性能的关键机制。

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