Composite Structures最新文献_第10页

Cracking composite design: Trace-driven scaling for cluster-based universal design 裂纹复合设计：基于簇的通用设计的轨迹驱动缩放

IF 7.1 2区材料科学 Q1 MATERIALS SCIENCE, COMPOSITES

Composite Structures

Pub Date : 2025-12-22 DOI: 10.1016/j.compstruct.2025.119984

Francesco Danzi

Traditional composite design requires bespoke material characterization and layup optimization for every new fiber–matrix system, creating significant delays and costs. We introduce a physics-based, trace-scaling framework that collapses hundreds of fiber–matrix–volume-fraction combinations into mechanically equivalent

π

-clusters, each defined by three non-dimensional stiffness ratios. By invoking Buckingham’s

π

-theorem, we show that materials with the same

π

-values share nearly identical normalized stiffness matrices, so their absolute stiffness scales only with the trace of the matrix. This finding overturns the notion of a “universal master-ply”, demonstrating instead that each

π

-cluster demands its own master-ply. A comprehensive sensitivity study, using Frobenius, eigenvalue, and spectral norms, reveals that

G_{12} / E_{1}

dominates the variability in mechanical response. We validate our method on 1 014 fiber–matrix–volume-fraction systems, applying K-means clustering in

π

-space to identify three robust clusters. Within each cluster, a single master-ply, defined as the centroid of the cluster, predicts the buckling loads of all cluster’s members with the error

< 3 %

, while the cross-cluster transfer incurs a much higher error. By restricting design to

π

-clusters, universal scaling laws emerge naturally, slashing optimization effort and enabling rapid, generalizable layup design for UD, woven, and hybrid composites alike. Finally, our approach recasts material selection and layup optimization into a unified, physics-grounded framework.

传统的复合材料设计需要为每个新的纤维基质系统定制材料特性和分层优化，这造成了很大的延迟和成本。我们引入了一个基于物理的、追踪尺度的框架，它将数百种纤维-基质-体积-分数组合折叠成机械等效的π-团簇，每个π-团簇由三个非三维刚度比定义。通过引用Buckingham π定理，我们证明了具有相同π值的材料具有几乎相同的归一化刚度矩阵，因此它们的绝对刚度仅与矩阵的迹线有关。这一发现推翻了“普遍主层”的概念，取而代之的是证明每个π-簇都需要自己的主层。利用Frobenius、特征值和谱规范进行的综合灵敏度研究表明，G12/E1在力学响应的变变性中占主导地位。我们在1 014个纤维-矩阵-体积-分数系统上验证了我们的方法，在π-空间中应用K-means聚类来识别三个鲁棒聚类。在每个簇中，单个主层（定义为簇的质心）预测簇中所有成员的屈曲载荷的误差为3%，而跨簇传递的误差要高得多。通过将设计限制为π-簇，通用缩放定律自然出现，减少了优化工作，并使快速，可通用的分层设计适用于UD，编织和混合复合材料。最后，我们的方法将材料选择和铺层优化改造成一个统一的、基于物理的框架。

{"title":"Cracking composite design: Trace-driven scaling for cluster-based universal design","authors":"Francesco Danzi","doi":"10.1016/j.compstruct.2025.119984","DOIUrl":"10.1016/j.compstruct.2025.119984","url":null,"abstract":"<div><div>Traditional composite design requires bespoke material characterization and layup optimization for every new fiber–matrix system, creating significant delays and costs. We introduce a physics-based, trace-scaling framework that collapses hundreds of fiber–matrix–volume-fraction combinations into mechanically equivalent <span><math><mi>π</mi></math></span>-clusters, each defined by three non-dimensional stiffness ratios. By invoking Buckingham’s <span><math><mi>π</mi></math></span>-theorem, we show that materials with the same <span><math><mi>π</mi></math></span>-values share nearly identical normalized stiffness matrices, so their absolute stiffness scales only with the trace of the matrix. This finding overturns the notion of a “universal master-ply”, demonstrating instead that each <span><math><mi>π</mi></math></span>-cluster demands its own master-ply. A comprehensive sensitivity study, using Frobenius, eigenvalue, and spectral norms, reveals that <span><math><mrow><msub><mrow><mi>G</mi></mrow><mrow><mn>12</mn></mrow></msub><mo>/</mo><msub><mrow><mi>E</mi></mrow><mrow><mn>1</mn></mrow></msub></mrow></math></span> dominates the variability in mechanical response. We validate our method on 1014 fiber–matrix–volume-fraction systems, applying K-means clustering in <span><math><mi>π</mi></math></span>-space to identify three robust clusters. Within each cluster, a single master-ply, defined as the centroid of the cluster, predicts the buckling loads of all cluster’s members with the error <span><math><mrow><mo><</mo><mn>3</mn><mtext>%</mtext></mrow></math></span>, while the cross-cluster transfer incurs a much higher error. By restricting design to <span><math><mi>π</mi></math></span>-clusters, universal scaling laws emerge naturally, slashing optimization effort and enabling rapid, generalizable layup design for UD, woven, and hybrid composites alike. Finally, our approach recasts material selection and layup optimization into a unified, physics-grounded framework.</div></div>","PeriodicalId":281,"journal":{"name":"Composite Structures","volume":"379 ","pages":"Article 119984"},"PeriodicalIF":7.1,"publicationDate":"2025-12-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145838219","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

In-situ remaining fatigue life prognosis for unidirectional polymer composite laminates based on modal frequency attenuation 基于模态频率衰减的单向聚合物复合材料层合板原位剩余疲劳寿命预测

IF 7.1 2区材料科学 Q1 MATERIALS SCIENCE, COMPOSITES

Composite Structures

Pub Date : 2025-12-22 DOI: 10.1016/j.compstruct.2025.119985

Jiaxing Sun , Lingyu Sun , Wenfeng Pan , Rihan Wang , Bingyan Shi

To address the challenge of in-situ fatigue damage prognosis in polymer matrix composite (PMC) laminates under cyclic loading, the acoustic emission technique offers high precision but is expensive, while the static strain–displacement method is economical but lacks sufficient accuracy. This study provides an in-situ fatigue life prognostic framework for unidirectional PMC laminates based on modal frequency attenuation. This approach evaluates stiffness degradation by measuring modal frequencies via impact hammer testing, eliminating the need for disassembly. It offers a cost-effective alternative to acoustic emission while surpassing the accuracy of strain–displacement method. This framework establishes three critical mapping relationships: (1) between remaining life and stiffness degradation, (2) between stiffness degradation and frequency attenuation, and (3) between frequency attenuation and failure characteristics (damage location and area). A demonstration using GFRP laminates under tension–tension cyclic loading shows that all predicted fatigue life values fall within a threefold error band of the experimental fatigue life. The proposed method provides a convenient, accurate, cost-effective, and rapid solution with significant engineering value.

针对聚合物基复合材料（PMC）层合板在循环载荷作用下的原位疲劳损伤预测问题，声发射技术精度高但成本高，而静态应变位移法经济但精度不够。提出了基于模态频率衰减的单向PMC层合板原位疲劳寿命预测框架。这种方法通过通过冲击锤测试测量模态频率来评估刚度退化，从而消除了拆卸的需要。它提供了一种具有成本效益的声发射替代方案，同时超越了应变位移法的精度。该框架建立了三个关键的映射关系：(1)剩余寿命与刚度退化之间的关系，(2)刚度退化与频率衰减之间的关系，以及(3)频率衰减与失效特征（损伤位置和面积）之间的关系。用GFRP复合材料进行拉伸-拉伸循环加载的试验表明，所有预测疲劳寿命值都在试验疲劳寿命的三倍误差范围内。该方法简便、准确、经济、快速，具有重要的工程价值。

{"title":"In-situ remaining fatigue life prognosis for unidirectional polymer composite laminates based on modal frequency attenuation","authors":"Jiaxing Sun , Lingyu Sun , Wenfeng Pan , Rihan Wang , Bingyan Shi","doi":"10.1016/j.compstruct.2025.119985","DOIUrl":"10.1016/j.compstruct.2025.119985","url":null,"abstract":"<div><div>To address the challenge of in-situ fatigue damage prognosis in polymer matrix composite (PMC) laminates under cyclic loading, the acoustic emission technique offers high precision but is expensive, while the static strain–displacement method is economical but lacks sufficient accuracy. This study provides an in-situ fatigue life prognostic framework for unidirectional PMC laminates based on modal frequency attenuation. This approach evaluates stiffness degradation by measuring modal frequencies via impact hammer testing, eliminating the need for disassembly. It offers a cost-effective alternative to acoustic emission while surpassing the accuracy of strain–displacement method. This framework establishes three critical mapping relationships: (1) between remaining life and stiffness degradation, (2) between stiffness degradation and frequency attenuation, and (3) between frequency attenuation and failure characteristics (damage location and area). A demonstration using GFRP laminates under tension–tension cyclic loading shows that all predicted fatigue life values fall within a threefold error band of the experimental fatigue life. The proposed method provides a convenient, accurate, cost-effective, and rapid solution with significant engineering value.</div></div>","PeriodicalId":281,"journal":{"name":"Composite Structures","volume":"379 ","pages":"Article 119985"},"PeriodicalIF":7.1,"publicationDate":"2025-12-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145838244","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A comparative study of adhesively bonded CFRP laminates under tensile and flexural tests CFRP粘接层合板拉伸和弯曲性能的对比研究

IF 7.1 2区材料科学 Q1 MATERIALS SCIENCE, COMPOSITES

Composite Structures

Pub Date : 2025-12-22 DOI: 10.1016/j.compstruct.2025.119991

Xiang Bao, Yaoning Sun, Di Wang, Wenhao Yao, Yifei Xu

The study comparatively investigates the failure mechanisms of carbon fiber reinforced polymer (CFRP) laminates adhesively bonded via stepped-lap and scarf joints subjected to bending and uniaxial tension. To achieve this objective, the mechanical properties of bonded CFRP structures were investigated through Abaqus finite element simulations and experimental testing (tensile and flexural tests). The experimental results demonstrate that scarf joints exhibit significantly superior bonding strength and Structural Strength under tensile and flexural loading compared to stepped-lap joints, with tensile and flexural strength improvements of 333.6 % and 394.2 %, respectively. This tensile and flexural strength enhancement stems from the optimized geometry of the scarf joint, which effectively mitigates stress concentrations. Macro-micro analyses indicated the main damage mode of both bonded structures was cohesive damage within the adhesive layer. For scarf joints, this cohesive failure mode prevailed at shorter lap lengths (10 mm, 20 mm), whereas failure modes became complex at 30 mm lap lengths, manifesting as the coexistence and interaction of cohesive failure, fiber fracture, and delamination. Further, numerical simulation results demonstrate high agreement with experimental data, as indicated by the deviations in ultimate load capacity of less than 10 %. The research reveals a comprehensive understanding of failure mechanisms in CFRP laminate bonding.

对比研究了碳纤维增强聚合物（CFRP）层合板阶梯式搭接和围巾式搭接在弯曲和单轴拉伸作用下的破坏机理。为了实现这一目标，通过Abaqus有限元模拟和实验测试（拉伸和弯曲测试）研究了粘结CFRP结构的力学性能。实验结果表明，在拉伸和弯曲载荷作用下，带状接头的粘结强度和结构强度均明显优于阶梯搭接接头，抗拉强度和弯曲强度分别提高了333.6%和394.2%。这种抗拉和抗弯强度的增强源于围巾接头的优化几何形状，有效地减轻了应力集中。宏微观分析表明，两种粘结结构的主要损伤模式均为粘结层内的内聚损伤。对于带状节理来说，这种内聚破坏模式在较短的搭接长度（10 mm和20 mm）时较为普遍，而在30 mm搭接长度时，这种破坏模式变得复杂，表现为内聚破坏、纤维断裂和分层的共存和相互作用。数值模拟结果与试验数据吻合较好，极限承载能力偏差小于10%。该研究揭示了对CFRP层合破坏机制的全面认识。

{"title":"A comparative study of adhesively bonded CFRP laminates under tensile and flexural tests","authors":"Xiang Bao, Yaoning Sun, Di Wang, Wenhao Yao, Yifei Xu","doi":"10.1016/j.compstruct.2025.119991","DOIUrl":"10.1016/j.compstruct.2025.119991","url":null,"abstract":"<div><div>The study comparatively investigates the failure mechanisms of carbon fiber reinforced polymer (CFRP) laminates adhesively bonded via stepped-lap and scarf joints subjected to bending and uniaxial tension. To achieve this objective, the mechanical properties of bonded CFRP structures were investigated through Abaqus finite element simulations and experimental testing (tensile and flexural tests). The experimental results demonstrate that scarf joints exhibit significantly superior bonding strength and Structural Strength under tensile and flexural loading compared to stepped-lap joints, with tensile and flexural strength improvements of 333.6 % and 394.2 %, respectively. This tensile and flexural strength enhancement stems from the optimized geometry of the scarf joint, which effectively mitigates stress concentrations. Macro-micro analyses indicated the main damage mode of both bonded structures was cohesive damage within the adhesive layer. For scarf joints, this cohesive failure mode prevailed at shorter lap lengths (10 mm, 20 mm), whereas failure modes became complex at 30 mm lap lengths, manifesting as the coexistence and interaction of cohesive failure, fiber fracture, and delamination. Further, numerical simulation results demonstrate high agreement with experimental data, as indicated by the deviations in ultimate load capacity of less than 10 %. The research reveals a comprehensive understanding of failure mechanisms in CFRP laminate bonding.</div></div>","PeriodicalId":281,"journal":{"name":"Composite Structures","volume":"379 ","pages":"Article 119991"},"PeriodicalIF":7.1,"publicationDate":"2025-12-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145838249","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Experimental research and modeling simulation of unidirectional thermoset prepreg considering non-constant bending stiffness 考虑非恒定弯曲刚度的单向热固性预浸料的实验研究与建模仿真

IF 7.1 2区材料科学 Q1 MATERIALS SCIENCE, COMPOSITES

Composite Structures

Pub Date : 2025-12-22 DOI: 10.1016/j.compstruct.2025.119995

Bolong Zhang, Liang Cheng, Tengbowen Wei, Huanyi Hu, Weidong Zhu, Yinglin Ke

During composite preforming, unidirectional (UD) thermoset prepregs are prone to out-of-plane wrinkling. To accurately predict such defects, this study investigates the mechanical properties of USN25000/7901 UD prepreg at 25 °C, focusing on bending stiffness. Free-cantilever bending tests of single-layer UD prepreg reveal strongly nonlinear bending moment–curvature (

M - κ

) responses in both the 0° and 90° directions, reflecting the material’s inherently non-constant bending stiffness, with the 90° bending stiffness much lower than that of 0°. The nonlinear

M - κ

responses are well captured by two independent Bi-Linear Bi-Material (BLBM) models. Simulations based on the BLBM model present that the predicted bending-moment accuracy improves by 42.39 % and 62.37 % in the 0° and 90° directions, respectively. The mean relative errors of the predicted free-cantilever deflection are 4.23 % and 3.39 % in the 0° and 90° directions, both superior to conventional models. The out-of-plane bending deformations from axial compression and 10° off-axis tensile simulations using the BLBM model also show better agreement with experiments. The normalized RMSE of the predicted 0° axial compression bending deformation remains within 5.5 %. These results demonstrate that the BLBM model offers a practical approach for predicting out-of-plane bending and wrinkling defects of UD prepregs during preforming.

在复合材料预成型过程中，单向热固性预浸料容易发生面外起皱。为了准确预测这类缺陷，本研究研究了USN25000/7901 UD预浸料在25℃下的力学性能，重点研究了弯曲刚度。单层UD预浸料的自由悬臂弯曲试验显示，在0°和90°方向上均存在强烈的非线性弯矩-曲率（M-κ）响应，反映了材料固有的非恒定弯曲刚度，其中90°弯曲刚度远低于0°弯曲刚度。非线性M-κ响应被两个独立的双线性双材料（BLBM）模型很好地捕获。基于BLBM模型的仿真结果表明，在0°和90°方向上，预测弯矩精度分别提高了42.39%和62.37%。在0°和90°方向上，自由悬臂梁挠度预测的平均相对误差分别为4.23%和3.39%，均优于传统模型。用BLBM模型模拟的轴向压缩和10°离轴拉伸引起的面外弯曲变形与实验结果吻合较好。预测的0°轴压弯曲变形归一化RMSE保持在5.5%以内。这些结果表明，BLBM模型为预测UD预浸料在预成型过程中的面外弯曲和起皱缺陷提供了一种实用的方法。

{"title":"Experimental research and modeling simulation of unidirectional thermoset prepreg considering non-constant bending stiffness","authors":"Bolong Zhang, Liang Cheng, Tengbowen Wei, Huanyi Hu, Weidong Zhu, Yinglin Ke","doi":"10.1016/j.compstruct.2025.119995","DOIUrl":"10.1016/j.compstruct.2025.119995","url":null,"abstract":"<div><div>During composite preforming, unidirectional (UD) thermoset prepregs are prone to out-of-plane wrinkling. To accurately predict such defects, this study investigates the mechanical properties of USN25000/7901 UD prepreg at 25 °C, focusing on bending stiffness. Free-cantilever bending tests of single-layer UD prepreg reveal strongly nonlinear bending moment–curvature (<span><math><mrow><mi>M</mi><mo>-</mo><mi>κ</mi></mrow></math></span>) responses in both the 0° and 90° directions, reflecting the material’s inherently non-constant bending stiffness, with the 90° bending stiffness much lower than that of 0°. The nonlinear <span><math><mrow><mi>M</mi><mo>-</mo><mi>κ</mi></mrow></math></span> responses are well captured by two independent Bi-Linear Bi-Material (BLBM) models. Simulations based on the BLBM model present that the predicted bending-moment accuracy improves by 42.39 % and 62.37 % in the 0° and 90° directions, respectively. The mean relative errors of the predicted free-cantilever deflection are 4.23 % and 3.39 % in the 0° and 90° directions, both superior to conventional models. The out-of-plane bending deformations from axial compression and 10° off-axis tensile simulations using the BLBM model also show better agreement with experiments. The normalized RMSE of the predicted 0° axial compression bending deformation remains within 5.5 %. These results demonstrate that the BLBM model offers a practical approach for predicting out-of-plane bending and wrinkling defects of UD prepregs during preforming.</div></div>","PeriodicalId":281,"journal":{"name":"Composite Structures","volume":"380 ","pages":"Article 119995"},"PeriodicalIF":7.1,"publicationDate":"2025-12-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145845516","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Pure shear static and fatigue tests in patch-repaired GFRP composites: The role of patch size and graphene nanoparticle reinforcement 贴片修复GFRP复合材料的纯剪切静力和疲劳试验：贴片尺寸和石墨烯纳米颗粒增强的作用

IF 7.1 2区材料科学 Q1 MATERIALS SCIENCE, COMPOSITES

Composite Structures

Pub Date : 2025-12-20 DOI: 10.1016/j.compstruct.2025.119946

Banamali Sahu , Chinmaya Kumar Sahoo , Ramadas Chennamsetti , A. Arockiarajan

Minor damages occurring in composite materials during operation often necessitate repair over discard. This study investigates the critical factors influencing such repairs: patch size and the adhesive bond at the patch-parent interface under pure shear, both in static and fatigue loading conditions. Initially, the specimens were subjected to static loading, and upon repairing a damaged composite laminate with 30 mm and 50 mm square patches, the ultimate shear strength was enhanced by 1% and 28%, respectively, compared to the original damaged sample. Further, modifying the patch parent interface with varying graphene nanoparticle (GNP) concentrations (0.3, 0.5, 0.7, and 0.9 wt%) resulted in 1% to 7% change in the ultimate shear strength. In case of fatigue loading, among the GNP-reinforced patch-repaired samples, all concentrations demonstrated notable improvements in fatigue life, with the 0.5 wt% GNP addition yielding the highest improvement of 285% compared to the unmodified samples. The damage events captured by the acoustic emission (AE) sensors are investigated to classify the different types of damage that occurred in the specimen during testing. Finally, various damage and failure patterns in the specimens were analyzed and reported using Digital Image Correlation (DIC) and infrared imaging.

复合材料在使用过程中发生的轻微损坏往往需要修复而不是丢弃。本研究探讨了影响这种修复的关键因素：在静载荷和疲劳载荷条件下，纯剪切作用下的贴片尺寸和贴片-母片界面的粘结程度。试验开始时，试件经受静载荷作用，用30mm和50mm正方形补片修复受损复合材料层合板后，其抗剪强度分别比原始损伤试样提高1%和28%。此外，用不同的石墨烯纳米颗粒（GNP）浓度（0.3、0.5、0.7和0.9 wt%）修改贴片母界面会导致最终抗剪强度变化1%至7%。在疲劳加载的情况下，在GNP增强补丁修复的样品中，所有浓度都显示出疲劳寿命的显著改善，与未改性的样品相比，添加0.5 wt% GNP产生的最大改善为285%。对声发射（AE）传感器捕获的损伤事件进行了研究，以对试件在测试过程中发生的不同类型的损伤进行分类。最后，利用数字图像相关（DIC）和红外成像技术对试件的各种损伤和破坏模式进行了分析和报道。

{"title":"Pure shear static and fatigue tests in patch-repaired GFRP composites: The role of patch size and graphene nanoparticle reinforcement","authors":"Banamali Sahu , Chinmaya Kumar Sahoo , Ramadas Chennamsetti , A. Arockiarajan","doi":"10.1016/j.compstruct.2025.119946","DOIUrl":"10.1016/j.compstruct.2025.119946","url":null,"abstract":"<div><div>Minor damages occurring in composite materials during operation often necessitate repair over discard. This study investigates the critical factors influencing such repairs: patch size and the adhesive bond at the patch-parent interface under pure shear, both in static and fatigue loading conditions. Initially, the specimens were subjected to static loading, and upon repairing a damaged composite laminate with 30 mm and 50 mm square patches, the ultimate shear strength was enhanced by 1% and 28%, respectively, compared to the original damaged sample. Further, modifying the patch parent interface with varying graphene nanoparticle (GNP) concentrations (0.3, 0.5, 0.7, and 0.9 wt%) resulted in 1% to 7% change in the ultimate shear strength. In case of fatigue loading, among the GNP-reinforced patch-repaired samples, all concentrations demonstrated notable improvements in fatigue life, with the 0.5 wt% GNP addition yielding the highest improvement of 285% compared to the unmodified samples. The damage events captured by the acoustic emission (AE) sensors are investigated to classify the different types of damage that occurred in the specimen during testing. Finally, various damage and failure patterns in the specimens were analyzed and reported using Digital Image Correlation (DIC) and infrared imaging.</div></div>","PeriodicalId":281,"journal":{"name":"Composite Structures","volume":"379 ","pages":"Article 119946"},"PeriodicalIF":7.1,"publicationDate":"2025-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145838178","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Low-velocity impact response of carbon fabric-reinforced shape memory polymer composites with toughening by aramid fiber blending 芳纶共混增韧碳纤维增强形状记忆聚合物复合材料的低速冲击响应

IF 7.1 2区材料科学 Q1 MATERIALS SCIENCE, COMPOSITES

Composite Structures

Pub Date : 2025-12-19 DOI: 10.1016/j.compstruct.2025.119980

Jiajun Chen , Chen Du , Chao Zhan , Penghui Zhu , He Liao , Teng Zhang , Qinghu Wang , Xiongqi Peng

This study experimentally investigates the low-velocity impact response of carbon woven fabric-reinforced shape memory polymer composites (SMPCs), focusing on the effects of carbon ply number (1 to 4 plies), impact energy (5.7 J, 7 J, 8.3 J and 9.6 J), and aramid fiber hybridization. Results reveal that the number of carbon layers strongly influences impact performance. SMPCs with two carbon layers (2C-SMPCs) exhibited the highest peak load and lowest structural integrity (SI) loss under 5.7 J and 7 J impacts, indicating a favorable balance between stiffness and damage tolerance. In contrast, increasing the ply count to 3 or 4 led to earlier damage initiation and more SI loss, reflecting reduced structural resilience. At 8.3 J, the 2C-SMPCs showed a 13.5 % reduction in peak load and a 55.5 % increase in maximum displacement, along with a distinct plastic deformation plateau. At 9.6 J, a decline in peak load, maximum displacement, and total energy absorption was observed, likely attributed to mechanical interlocking caused by fiber bundle rearrangement. Hybridization with aramid fibers improved energy dissipation and impact toughness. The hybrid SMPC with one carbon and one aramid layer exhibited the longest impact duration and highest energy absorption at 5.7 J and 7.0 J, while maintaining low SI loss compared to both 2C-SMPCs and SMPCs reinforced solely with aramid fibers. These findings demonstrate that a moderate carbon ply count optimizes impact stiffness and SI, and aramid hybridization provides significant gains in toughness and energy dissipation, offering effective design strategies for multifunctional SMPC structures under dynamic loading.

实验研究了碳机织物增强形状记忆聚合物复合材料（SMPCs）的低速冲击响应，重点研究了碳层数（1 ~ 4层）、冲击能（5.7 J、7 J、8.3 J和9.6 J）以及芳纶纤维杂化对SMPCs低速冲击响应的影响。结果表明，碳层的数量对冲击性能有很大影响。在5.7 J和7 J的冲击下，具有两层碳层的smpc （2c - smpc）表现出最高的峰值载荷和最低的结构完整性损失，表明其在刚度和损伤容限之间取得了良好的平衡。相比之下，将厚度增加到3或4会导致更早的损伤发生和更多的SI损失，这反映了结构弹性的降低。在8.3 J时，2c - smpc的峰值载荷降低了13.5%，最大位移增加了55.5%，同时出现了明显的塑性变形平台。在9.6 J时，观察到峰值载荷、最大位移和总能量吸收下降，这可能归因于纤维束重排引起的机械联锁。芳纶纤维的杂化改善了能量耗散和冲击韧性。与2c -SMPC和单纯芳纶增强SMPC相比，单碳单芳纶复合SMPC具有最长的冲击持续时间和最高的能量吸收，分别为5.7 J和7.0 J，同时具有较低的SI损失。这些发现表明，适度的碳层数可以优化冲击刚度和SI，芳纶杂化可以显著提高韧性和能量耗散，为动态载荷下多功能SMPC结构的设计提供了有效的策略。

{"title":"Low-velocity impact response of carbon fabric-reinforced shape memory polymer composites with toughening by aramid fiber blending","authors":"Jiajun Chen , Chen Du , Chao Zhan , Penghui Zhu , He Liao , Teng Zhang , Qinghu Wang , Xiongqi Peng","doi":"10.1016/j.compstruct.2025.119980","DOIUrl":"10.1016/j.compstruct.2025.119980","url":null,"abstract":"<div><div>This study experimentally investigates the low-velocity impact response of carbon woven fabric-reinforced shape memory polymer composites (SMPCs), focusing on the effects of carbon ply number (1 to 4 plies), impact energy (5.7 J, 7 J, 8.3 J and 9.6 J), and aramid fiber hybridization. Results reveal that the number of carbon layers strongly influences impact performance. SMPCs with two carbon layers (2C-SMPCs) exhibited the highest peak load and lowest structural integrity (SI) loss under 5.7 J and 7 J impacts, indicating a favorable balance between stiffness and damage tolerance. In contrast, increasing the ply count to 3 or 4 led to earlier damage initiation and more SI loss, reflecting reduced structural resilience. At 8.3 J, the 2C-SMPCs showed a 13.5 % reduction in peak load and a 55.5 % increase in maximum displacement, along with a distinct plastic deformation plateau. At 9.6 J, a decline in peak load, maximum displacement, and total energy absorption was observed, likely attributed to mechanical interlocking caused by fiber bundle rearrangement. Hybridization with aramid fibers improved energy dissipation and impact toughness. The hybrid SMPC with one carbon and one aramid layer exhibited the longest impact duration and highest energy absorption at 5.7 J and 7.0 J, while maintaining low SI loss compared to both 2C-SMPCs and SMPCs reinforced solely with aramid fibers. These findings demonstrate that a moderate carbon ply count optimizes impact stiffness and SI, and aramid hybridization provides significant gains in toughness and energy dissipation, offering effective design strategies for multifunctional SMPC structures under dynamic loading.</div></div>","PeriodicalId":281,"journal":{"name":"Composite Structures","volume":"379 ","pages":"Article 119980"},"PeriodicalIF":7.1,"publicationDate":"2025-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145838183","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Theoretical prediction and design optimization of foreign-object impact resistance of graded metal foam sandwich panels 梯度金属泡沫夹芯板抗外来物冲击性能的理论预测与设计优化

IF 7.1 2区材料科学 Q1 MATERIALS SCIENCE, COMPOSITES

Composite Structures

Pub Date : 2025-12-19 DOI: 10.1016/j.compstruct.2025.119975

Zhenhao Yu, Xiongfei Zhou, Lin Jing

To enhance the operational safety of high-speed rotating test equipment and avoid potential debris ejection impact risks by component failure, a sandwich structure with a gradient metal foam core was designed and utilized for the protective structure to resist the possible foreign-object impact from the high-speed rotating test equipment in this study. First, a predictive formula for the residual velocity of the sandwich structure under projectile impact loading was derived using the minimum potential energy theory, which can generate a design chart and provide geometric optimization pathways of the lightweight configuration. Whereafter, a finite element (FE) model of the metal foam core sandwich panel was established and validated against both theoretical calculations and experimental results. A multi-objective optimization was finally performed through a multinomial response surface methodology, combined with a non-dominated sorting genetic algorithm (NSGA-II), targeting key design variables such as face-sheet thickness, core thickness, and core layered-gradient distribution. The results demonstrate that the proposed theoretical model can accurately predict the residual velocity of the gradient core sandwich panel, with a maximum relative error below 10 % compared to simulation results, thereby offering valuable guidance for engineering applications. The optimized sandwich structure showed significant improvements in penetration resistance capacity; specifically, the critical ballistic velocities increased by 196.00 %, 191.43 %, and 166.95 % compared with the positive gradient, negative gradient, and uniform core configurations, respectively. Furthermore, the optimized gradient core sandwich panel achieved a higher critical ballistic velocity, which is 8.90 % higher than the uniform core sandwich panel of equivalent mass.

为了提高高速旋转试验设备的运行安全性，避免部件失效可能带来的弹射碎片冲击风险，本研究设计并利用梯度金属泡沫芯夹层结构作为防护结构，抵御高速旋转试验设备可能产生的异物冲击。首先，利用最小势能理论推导了弹丸冲击载荷作用下夹层结构剩余速度的预测公式，生成了设计图形，提供了轻量化构型的几何优化路径；在此基础上，建立了金属泡沫芯夹芯板的有限元模型，并对理论计算和实验结果进行了验证。最后，采用多项响应面法结合非支配排序遗传算法（NSGA-II），针对面板厚度、岩心厚度、岩心分层梯度分布等关键设计变量进行多目标优化。结果表明，该理论模型能够准确预测梯度岩心夹层板的残余速度，与仿真结果相比，最大相对误差在10%以下，为工程应用提供了有价值的指导。优化后的夹层结构抗侵彻能力显著提高；其中，临界弹道速度分别比正梯度、负梯度和均匀型芯分别提高了196.00%、191.43%和166.95%。优化后的梯度芯芯夹芯板具有更高的临界弹道速度，比同等质量的均匀芯芯夹芯板高8.90%。

{"title":"Theoretical prediction and design optimization of foreign-object impact resistance of graded metal foam sandwich panels","authors":"Zhenhao Yu, Xiongfei Zhou, Lin Jing","doi":"10.1016/j.compstruct.2025.119975","DOIUrl":"10.1016/j.compstruct.2025.119975","url":null,"abstract":"<div><div>To enhance the operational safety of high-speed rotating test equipment and avoid potential debris ejection impact risks by component failure, a sandwich structure with a gradient metal foam core was designed and utilized for the protective structure to resist the possible foreign-object impact from the high-speed rotating test equipment in this study. First, a predictive formula for the residual velocity of the sandwich structure under projectile impact loading was derived using the minimum potential energy theory, which can generate a design chart and provide geometric optimization pathways of the lightweight configuration. Whereafter, a finite element (FE) model of the metal foam core sandwich panel was established and validated against both theoretical calculations and experimental results. A multi-objective optimization was finally performed through a multinomial response surface methodology, combined with a non-dominated sorting genetic algorithm (NSGA-II), targeting key design variables such as face-sheet thickness, core thickness, and core layered-gradient distribution. The results demonstrate that the proposed theoretical model can accurately predict the residual velocity of the gradient core sandwich panel, with a maximum relative error below 10 % compared to simulation results, thereby offering valuable guidance for engineering applications. The optimized sandwich structure showed significant improvements in penetration resistance capacity; specifically, the critical ballistic velocities increased by 196.00 %, 191.43 %, and 166.95 % compared with the positive gradient, negative gradient, and uniform core configurations, respectively. Furthermore, the optimized gradient core sandwich panel achieved a higher critical ballistic velocity, which is 8.90 % higher than the uniform core sandwich panel of equivalent mass.</div></div>","PeriodicalId":281,"journal":{"name":"Composite Structures","volume":"379 ","pages":"Article 119975"},"PeriodicalIF":7.1,"publicationDate":"2025-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145838180","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Lithiation-induced buckling behavior of solid polymer electrolytes based all-solid-state lithium batteries 基于固体聚合物电解质的全固态锂电池的锂离子诱导屈曲行为

IF 7.1 2区材料科学 Q1 MATERIALS SCIENCE, COMPOSITES

Composite Structures

Pub Date : 2025-12-19 DOI: 10.1016/j.compstruct.2025.119982

Qinghua Yang , Detao Kong , Yaolong He , Hongjiu Hu

All-solid-state lithium batteries (ASSLBs) employing the solid polymer electrolytes (SPEs) have garnered significant interest as promising candidates for flexible and stretchable energy storage. However, the batteries may suffer from lithium diffusion-induced buckling during operation. This study aims to evaluate the resistance to lithium-induced buckling in ASSLBs incorporating poly(ethylene oxide) (PEO)-based SPEs. To this end, constitutive models for the SPE, LiFePO4 cathode and lithium metal were developed based on uniaxial tensile data obtained from the individual battery components. The effects of operating conditions, SPE pre-stretching, component sizes and interfacial adhesion on the buckling behavior of pouch-type ASSLBs were examined. The results indicate that the critical state of charge for buckling initiation decreases with rising temperature and higher discharge rates. Pre-stretching the SPE was found to enhance the cell’s buckling resistance and concurrently increase its ionic conductivity. However, residual stresses from pre-stretching weakened the mechanical properties. Furthermore, the mechanical stability of ASSLBs can be improved by reducing the cell’s in-plane dimensions or employing thicker current collectors. Moreover, the adhesion strength between the SPE and electrodes proved to be a critical factor governing buckling resistance. These findings offer insights for the design of ASSLBs with superior mechanical stability.

采用固体聚合物电解质（spe）的全固态锂电池（ASSLBs）作为柔性和可拉伸能量存储的有前途的候选者已经引起了人们的极大兴趣。然而，在使用过程中，电池可能会受到锂扩散引起的屈曲。本研究旨在评估含有聚环氧乙烷（PEO）基spe的asslb对锂诱导屈曲的抗性。为此，基于从单个电池组件获得的单轴拉伸数据，建立了SPE、LiFePO4阴极和锂金属的本构模型。考察了操作条件、SPE预拉伸、组分尺寸和界面黏附对袋式asslb屈曲行为的影响。结果表明：随着温度的升高和放电速率的增大，起曲临界电荷状态减小；预拉伸固相萃取可以提高电池的抗屈曲性能，同时提高其离子电导率。然而，预拉伸产生的残余应力削弱了材料的力学性能。此外，asslb的机械稳定性可以通过减小电池的面内尺寸或采用更厚的集流器来改善。此外，SPE与电极之间的粘附强度被证明是控制屈曲抗力的关键因素。这些发现为设计具有优异机械稳定性的asslb提供了见解。

{"title":"Lithiation-induced buckling behavior of solid polymer electrolytes based all-solid-state lithium batteries","authors":"Qinghua Yang , Detao Kong , Yaolong He , Hongjiu Hu","doi":"10.1016/j.compstruct.2025.119982","DOIUrl":"10.1016/j.compstruct.2025.119982","url":null,"abstract":"<div><div>All-solid-state lithium batteries (ASSLBs) employing the solid polymer electrolytes (SPEs) have garnered significant interest as promising candidates for flexible and stretchable energy storage. However, the batteries may suffer from lithium diffusion-induced buckling during operation. This study aims to evaluate the resistance to lithium-induced buckling in ASSLBs incorporating poly(ethylene oxide) (PEO)-based SPEs. To this end, constitutive models for the SPE, LiFePO4 cathode and lithium metal were developed based on uniaxial tensile data obtained from the individual battery components. The effects of operating conditions, SPE pre-stretching, component sizes and interfacial adhesion on the buckling behavior of pouch-type ASSLBs were examined. The results indicate that the critical state of charge for buckling initiation decreases with rising temperature and higher discharge rates. Pre-stretching the SPE was found to enhance the cell’s buckling resistance and concurrently increase its ionic conductivity. However, residual stresses from pre-stretching weakened the mechanical properties. Furthermore, the mechanical stability of ASSLBs can be improved by reducing the cell’s in-plane dimensions or employing thicker current collectors. Moreover, the adhesion strength between the SPE and electrodes proved to be a critical factor governing buckling resistance. These findings offer insights for the design of ASSLBs with superior mechanical stability.</div></div>","PeriodicalId":281,"journal":{"name":"Composite Structures","volume":"379 ","pages":"Article 119982"},"PeriodicalIF":7.1,"publicationDate":"2025-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145838194","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Enhancing mechanisms of electro-spun nanofiber veils on the low-velocity impact and residual compressive performances of carbon fiber reinforced aluminum laminates 电纺纳米纤维膜对碳纤维增强铝层板低速冲击和残余压缩性能的增强机理

IF 7.1 2区材料科学 Q1 MATERIALS SCIENCE, COMPOSITES

Composite Structures

Pub Date : 2025-12-19 DOI: 10.1016/j.compstruct.2025.119978

Chenxi Lv , Yuan Lin , Mingyang Wang , Zhongwei Zhang , Huaguan Li , Chunming Song , Xiaoqing Dai

Carbon fiber reinforced aluminum laminates (CARALL) are susceptible to delamination damage under impact loads, which can severely affect structural safety in engineering applications. To enhance the impact resistance of CARALL, interfacial toughening strategies incorporating varied metal surface treatment methods and interleaving electro-spun nanofiber veils between individual layers were developed in this work. Low-velocity impact performances and detailed failure morphologies were experimentally compared first between specimens with varied interfacial conditions. Three-dimensional progressive damage numerical analysis were further conducted to reveal the energy dissipation mechanisms. Then the residual compressive strength was evaluated, with the deformation characteristics captured by digital image correlation techniques. Finally, an in-depth analysis was carried out to understand the enhancement mechanisms of interfacial conditions on the impact resistance of CARALL. The results showed that the specimens with nanofiber veils interleaving at aluminum alloy/adhesive interfaces exhibited the best impact resistance. More enhancements were introduced by the nanofiber veils to the specimens with aluminum layers treated by sandpaper grinding than the ones with plasma treatment. Compared to raw sandpaper grinded specimens, the impact damage volume of interleaved ones were reduced by 17.1 % to the maximum. Besides, the residual compressive strength was evidently improved after interleaving, regardless of metal surface treatment methods.

碳纤维增强铝层压板（CARALL）在冲击载荷作用下易发生分层损伤，严重影响工程应用中的结构安全。为了提高CARALL的抗冲击性，本研究开发了结合不同金属表面处理方法的界面增韧策略和在各层之间交织电纺纳米纤维面纱。实验首先比较了不同界面条件下试样的低速冲击性能和详细的破坏形态。进一步进行了三维渐进损伤数值分析，揭示了能量耗散机制。然后利用数字图像相关技术捕获变形特征，对残余抗压强度进行评估。最后，深入分析了界面条件对CARALL抗冲击性能的增强机理。结果表明，在铝合金/胶粘剂界面处，纳米纤维膜交织的试样具有最佳的抗冲击性能。与等离子体处理相比，砂纸处理对铝层的增强效果更好。与原砂纸研磨试样相比，交错试样的冲击损伤体积最大减小了17.1%。此外，无论金属表面处理方式如何，交错处理后的残余抗压强度都有明显提高。

{"title":"Enhancing mechanisms of electro-spun nanofiber veils on the low-velocity impact and residual compressive performances of carbon fiber reinforced aluminum laminates","authors":"Chenxi Lv , Yuan Lin , Mingyang Wang , Zhongwei Zhang , Huaguan Li , Chunming Song , Xiaoqing Dai","doi":"10.1016/j.compstruct.2025.119978","DOIUrl":"10.1016/j.compstruct.2025.119978","url":null,"abstract":"<div><div>Carbon fiber reinforced aluminum laminates (CARALL) are susceptible to delamination damage under impact loads, which can severely affect structural safety in engineering applications. To enhance the impact resistance of CARALL, interfacial toughening strategies incorporating varied metal surface treatment methods and interleaving electro-spun nanofiber veils between individual layers were developed in this work. Low-velocity impact performances and detailed failure morphologies were experimentally compared first between specimens with varied interfacial conditions. Three-dimensional progressive damage numerical analysis were further conducted to reveal the energy dissipation mechanisms. Then the residual compressive strength was evaluated, with the deformation characteristics captured by digital image correlation techniques. Finally, an in-depth analysis was carried out to understand the enhancement mechanisms of interfacial conditions on the impact resistance of CARALL. The results showed that the specimens with nanofiber veils interleaving at aluminum alloy/adhesive interfaces exhibited the best impact resistance. More enhancements were introduced by the nanofiber veils to the specimens with aluminum layers treated by sandpaper grinding than the ones with plasma treatment. Compared to raw sandpaper grinded specimens, the impact damage volume of interleaved ones were reduced by 17.1 % to the maximum. Besides, the residual compressive strength was evidently improved after interleaving, regardless of metal surface treatment methods.</div></div>","PeriodicalId":281,"journal":{"name":"Composite Structures","volume":"379 ","pages":"Article 119978"},"PeriodicalIF":7.1,"publicationDate":"2025-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145838264","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Pressure-dependent strain gradient plasticity for micro-mechanical analyses of fibre-reinforced polymers 纤维增强聚合物微力学分析的压力依赖应变梯度塑性

IF 7.1 2区材料科学 Q1 MATERIALS SCIENCE, COMPOSITES

Composite Structures

Pub Date : 2025-12-19 DOI: 10.1016/j.compstruct.2025.119965

Igor A. Rodrigues Lopes , A. Francisca Carvalho Alves , Nathan Klavzer , Thomas Pardoen , Pedro P. Camanho

A new constitutive model for epoxy resins is proposed to accurately capture the micro-scale strain fields in fibre-reinforced composites. The model extends conventional plasticity by introducing strain-gradient effects through an implicit gradient formulation that accounts for pressure sensitivity and asymmetric tension/compression behaviour-critical features to represent the mechanical response of epoxies at small scales. The formulation is implemented in a commercial finite element platform through user-defined subroutines and solved via an analogy with coupled thermo-mechanical problems that include Helmholtz-type equations. The ability of the model to predict the size-dependent response and to prevent unrealistic overpredictions of strain magnitude is illustrated through the simulation of nanoindentation on neat epoxy and of the local strain field behaviour in a composite. The results are compared with experimental data, which are also used to calibrate the additional constitutive parameters through a composite Bayesian optimization strategy. The proposed framework significantly improves the predictive capabilities of micromechanical models for composite materials by incorporating scale-dependent plasticity mechanisms.

为了准确捕捉纤维增强复合材料的微尺度应变场，提出了一种新的环氧树脂本构模型。该模型通过隐式梯度公式引入应变梯度效应，扩展了传统的塑性，该公式考虑了压力敏感性和不对称拉伸/压缩行为的关键特征，以表示环氧树脂在小尺度上的机械响应。该公式通过用户定义的子程序在商业有限元平台上实现，并通过类比包括亥姆霍兹型方程的耦合热-力学问题来求解。通过模拟环氧树脂上的纳米压痕和复合材料中的局部应变场行为，说明了该模型预测尺寸相关响应和防止应变幅度不切实际的过度预测的能力。结果与实验数据进行了比较，并通过复合贝叶斯优化策略对附加本构参数进行了标定。该框架通过纳入尺度相关的塑性机制，显著提高了复合材料微观力学模型的预测能力。

{"title":"Pressure-dependent strain gradient plasticity for micro-mechanical analyses of fibre-reinforced polymers","authors":"Igor A. Rodrigues Lopes , A. Francisca Carvalho Alves , Nathan Klavzer , Thomas Pardoen , Pedro P. Camanho","doi":"10.1016/j.compstruct.2025.119965","DOIUrl":"10.1016/j.compstruct.2025.119965","url":null,"abstract":"<div><div>A new constitutive model for epoxy resins is proposed to accurately capture the micro-scale strain fields in fibre-reinforced composites. The model extends conventional plasticity by introducing strain-gradient effects through an implicit gradient formulation that accounts for pressure sensitivity and asymmetric tension/compression behaviour-critical features to represent the mechanical response of epoxies at small scales. The formulation is implemented in a commercial finite element platform through user-defined subroutines and solved via an analogy with coupled thermo-mechanical problems that include Helmholtz-type equations. The ability of the model to predict the size-dependent response and to prevent unrealistic overpredictions of strain magnitude is illustrated through the simulation of nanoindentation on neat epoxy and of the local strain field behaviour in a composite. The results are compared with experimental data, which are also used to calibrate the additional constitutive parameters through a composite Bayesian optimization strategy. The proposed framework significantly improves the predictive capabilities of micromechanical models for composite materials by incorporating scale-dependent plasticity mechanisms.</div></div>","PeriodicalId":281,"journal":{"name":"Composite Structures","volume":"381 ","pages":"Article 119965"},"PeriodicalIF":7.1,"publicationDate":"2025-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145903994","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0