【新文速递】2024年10月17日固体力学SCI期刊最新文章

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今日更新：International Journal of Solids and Structures 1 篇，Journal of the Mechanics and Physics of Solids 1 篇，Mechanics of Materials 1 篇，Thin-Walled Structures 3 篇

International Journal of Solids and Structures

Hydro-mechanical modeling of cohesive crack propagation of concrete lining in high internal pressure tunnels

Junchao Jin, Laihong Jing, Zhiyu Song, Kai Su, Fengwei Yang, Zhengxiong Bai

doi:10.1016/j.ijsolstr.2024.113108

高内压隧道混凝土衬砌内聚裂缝扩展的水力学模拟

High pressure tunnels with concrete lining have been extensively utilized in project practice. However, due to the characteristic of concrete being susceptible to cracking under tension, the lining inevitably develops cracks under high internal water pressure, posing a serious threat to the operation of tunnels. This study aims at developing a hydro-mechanical numerical model of cohesive crack propagation of concrete lining in high internal pressure tunnels. In this regard, the determination of cohesive element parameters is elucidated, the contact simulation within the software ABAQUS is improved to accurately characterize the interface between lining and surrounding rock, and the numerical calculation process in ABAQUS is realized using indirect coupled method. The simulation results align well with the physical model test and engineering monitoring data, demonstrating that the proposed method can accurately simulate the hydraulic interactions of high pressure tunnel. Additionally, a comparison with calculation models employing tie constraints to simulate the lining-surrounding rock interface is conducted. Finally, comparison with traditional continuum method reveals that while both methods exhibit consistent overall trends. It is recommended to choose the proposed method when describing the discontinuous propagation process of cracks, which cannot be simulated by the continuum analysis method.

高压混凝土衬砌隧道在工程实践中得到了广泛的应用。然而，由于混凝土在受拉作用下易开裂的特性，衬砌在高内水压作用下不可避免地出现裂缝，对隧道的运行构成严重威胁。本研究旨在建立高内压隧道混凝土衬砌内聚裂缝扩展的水力学数值模型。在此基础上，阐述了黏结单元参数的确定，改进了ABAQUS软件中的接触模拟，以准确表征衬砌与围岩界面，并采用间接耦合方法实现了ABAQUS中的数值计算过程。仿真结果与物理模型试验和工程监测数据吻合较好，表明该方法能较准确地模拟高压隧洞的水力相互作用。并与采用约束条件模拟衬砌-围岩界面的计算模型进行了比较。最后，与传统连续统方法的比较表明，两种方法的总体趋势是一致的。在描述裂纹的不连续扩展过程时，建议采用本文提出的方法，连续统分析法无法模拟这一过程。

Journal of the Mechanics and Physics of Solids

On the role of the retained porosity on the shock response of additively manufactured high-performance steel: experiments, constitutive model and finite-element predictions

Benoit Revil-Baudard, Peter Sable, Oana Cazacu, Bernard Gaskey, Sujeily Soto-Medina

doi:10.1016/j.jmps.2024.105909

残余孔隙率对增材制造高性能钢冲击响应的影响：实验、本构模型和有限元预测

Experiments have shown that for quasi-static and moderate strain-rates (of the order of 102-103/s) the mechanical response of additively manufactured (AM) and traditionally processed high-strength steels is similar whereas the impact behavior is markedly different. In this paper, we reveal that the main reason for this difference is the retained porosity in the AM material. Fully-implicit finite element calculations are presented in which we simulate both the launching of the impact plate and the impact between the two plates. The constitutive model used is the elastic/plastic model for porous ductile materials with matrix displaying tension-compression asymmetry and Johnson-Cook hardening law that accounts for both strain-rate effects and plastic history. It is shown that even a very small initial porosity changes the wave front, decreases the Hugoniot while increasing the shock rise time, when compared to a void free material. Furthermore, quantitative comparisons between simulation results and plate impact data for both the AM and the wrought AF9628 steel are provided. The good agreement show that the model captures the impact response and illustrates the model capabilities to provide information on field variables that cannot be directly measured.Additive manufacturing (AM) of metals is rapidly advancing as a robust method for production of geometrically complex parts. To enhance understanding of material performance and open up additional application opportunities, dynamic characterization of newly printed alloys is required to validate their effectiveness. In this paper, we present results from plate impact testing of AF9628 steel, a newly developed high-strength low alloy martensitic steel for structural applications which require resistance to high-rate deformation. We put into evidence differences in the shock structure between the AM and the traditionally processed material. To gain understanding, we conduct fully-implicit finite element (FE) calculations in which we model both the launching of the impact plate and the impact between the two plates, respectively. An elastic/plastic damage model that accounts for the effects of the tension-compression asymmetry in plastic deformation and its influence on porosity evolution is used. The FE results reveal that even a very small amount of initial porosity leads to an increase in the shock rise time, explaining the observed trends. Furthermore, quantitative comparisons between simulation results and plate impact data for both the AM and the wrought AF9628 are provided. The good agreement show that the model captures the impact response and illustrates the model capabilities to provide information on field variables that cannot be directly measured.

实验表明，在准静态和中等应变速率（102 ~ 103/s量级）下，增材制造和传统加工的高强钢的力学响应相似，但冲击行为有明显不同。在本文中，我们揭示了这种差异的主要原因是AM材料中保留的孔隙率。在全隐式有限元计算中，我们模拟了冲击板的发射和两板之间的碰撞。采用的本构模型为多孔延性材料的弹塑性模型，基体呈现拉压不对称，Johnson-Cook硬化规律兼顾应变率效应和塑性历史。结果表明，与无孔隙材料相比，即使初始孔隙率很小，也会改变波前，降低Hugoniot，同时增加激波上升时间。此外，还提供了模拟结果与AM和变形后的AF9628钢的板冲击数据的定量比较。良好的一致性表明，该模型捕获了冲击响应，并说明了该模型能够提供无法直接测量的现场变量的信息。金属增材制造（AM）作为一种生产几何复杂零件的强大方法正在迅速发展。为了加强对材料性能的理解并开辟更多的应用机会，需要对新打印的合金进行动态表征以验证其有效性。本文介绍了AF9628钢板冲击试验的结果，AF9628是一种新开发的高强度低合金马氏体钢，用于要求抗高速变形的结构应用。我们证明了AM和传统加工材料在冲击结构上的差异。为了获得理解，我们进行了全隐式有限元（FE）计算，其中我们分别模拟了撞击板的发射和两个板之间的撞击。采用了考虑塑性变形中拉压不对称性及其对孔隙度演化影响的弹塑性损伤模型。有限元结果表明，即使是非常小的初始孔隙率也会导致冲击上升时间的增加，这解释了观察到的趋势。此外，还对AM和变形后的AF9628的模拟结果与板冲击数据进行了定量比较。良好的一致性表明，该模型捕获了冲击响应，并说明了该模型能够提供无法直接测量的现场变量的信息。

Mechanics of Materials

Low-dose neutron irradiation effects on the elastoplastic deformation mechanisms of aluminum-doped gallium nitride under contact loading

Tiankun Li, Pengfei Zhao, Fulin Shang

doi:10.1016/j.mechmat.2024.105180

低剂量中子辐照对接触载荷下掺铝氮化镓弹塑性变形机制的影响

The elastoplastic deformation mechanisms of irradiated aluminum (Al)-doped gallium nitride (GaN) under contact loading are investigated in this work using the nanoindentation simulations, which is of great significance for understanding the mechanical properties of the Al-doped GaN and guiding the design of durable and high-performance GaN-based devices. The mechanical behaviors of the Al-doped GaN with different doping concentrations are analyzed, including the indentation hardness, Young's modulus, elastic recovery rates, phase transformations, and stress distribution. It is found that Al doping increases their hardness, Young's modulus, and elastic recovery rates, and leads to an enlargement of the phase transformation regions, which is dominated by the high coordination number (CN) phase transformations. Furthermore, the effects of low-dose neutron irradiation on their elastoplastic deformation mechanisms are studied by triggering cascade collisions within the structure. When subjected to such irradiation, structural changes occur in the Al-doped GaN, their indentation hardness, Young's modulus, and elastic recovery rates increase remarkably, and its phase transformation mechanism is changed remarkably. The dislocation behaviors of the doped and undoped GaN are different under neutron irradiation. This study is important for capturing the mechanical stability and integrity of Al-doped GaN in an irradiation environment, as well as developing GaN-based devices with superior irradiation resistance.

本文采用纳米压痕模拟方法研究了辐照铝掺杂氮化镓（GaN）在接触载荷作用下的弹塑性变形机理，这对于理解掺铝氮化镓的力学性能，指导设计耐用、高性能的氮化镓器件具有重要意义。分析了不同掺杂浓度al掺杂GaN的力学行为，包括压痕硬度、杨氏模量、弹性回复率、相变和应力分布。结果表明，Al的掺入增加了合金的硬度、杨氏模量和弹性回复率，并导致相变区域的扩大，其中以高配位数（CN）相变为主。此外，通过触发结构内部的级联碰撞，研究了低剂量中子辐照对其弹塑性变形机制的影响。在这种辐照下，掺al GaN的结构发生了变化，压痕硬度、杨氏模量和弹性回复率显著提高，相变机理发生了显著变化。在中子辐照下，掺杂氮化镓和未掺杂氮化镓的位错行为不同。该研究对于捕获al掺杂GaN在辐照环境中的机械稳定性和完整性，以及开发具有优异耐辐照性的GaN基器件具有重要意义。

Thin-Walled Structures

Intelligent design of multi-layered variable stiffness composite structure based on transfer learning

Kunpeng zhang, Hongjiang Liu, Shaojun Feng, Long Li, Dachuan Liu, Peng Hao, Zekai Huo, Jing Li

doi:10.1016/j.tws.2024.112588

基于迁移学习的多层变刚度复合材料结构智能设计

Variable stiffness composite structures offer more flexible design space than thin-walled metal structures and have greater potential for vibration-resistant design. When faced with multiple new types of design problems, the complex modelling and analysis procedures frequently prove to be both time-consuming and costly in terms of optimization. In this study, an innovative multi-layered variable stiffness (MVS) composite structure with high design flexibility is proposed, with images representation for curvilinearly stiffened paths, non-uniform layouts, and fiber and layup angles. Moreover, an intelligent optimization method based on transfer learning is proposed for addressing a variety of factors affecting dynamic design, including boundary types, structural features, and dynamic responses. The objective of the transfer learning model is to facilitate the inheritance and sharing of variable stiffness features, thereby enabling the efficient design of new problems with limited datasets. The validation of different examples shows that the transfer learning can effectively acquire the structural features from the existing source domain datasets, thereby significantly reducing the data for some new target domains by approximately 50%. In comparison to the initial constant stiffness (CS) structures, the different optimized configurations indicate that the MVS composite structures are capable of effectively enhancing the dynamic responses by 10%∼146% for natural frequency and dynamic compliance. Furthermore, the MVS optimized configuration displays superior dynamic responses in some problems, when compared to the CS optimized configuration.

变刚度复合材料结构提供了比薄壁金属结构更灵活的设计空间，具有更大的抗振动设计潜力。当面临多种新型设计问题时，复杂的建模和分析过程往往证明在优化方面既耗时又昂贵。本研究提出了一种具有高设计灵活性的创新型多层变刚度（MVS）复合材料结构，该结构具有曲线加筋路径、非均匀布局、纤维和铺层角度的图像表示。此外，针对边界类型、结构特征和动态响应等影响动态设计的多种因素，提出了一种基于迁移学习的智能优化方法。迁移学习模型的目标是促进变刚度特征的继承和共享，从而在有限的数据集上有效地设计新问题。不同示例的验证表明，迁移学习可以有效地从现有的源域数据集中获取结构特征，从而显著减少一些新目标域的数据量，减少了约50%。与初始恒刚度（CS）结构相比，不同的优化配置表明，MVS复合结构的固有频率和动态柔度能够有效地提高10% ~ 146%的动态响应。此外，与CS优化构型相比，MVS优化构型在某些问题上表现出更好的动态响应。

Digital Image Correlation in Extreme Conditions

Bo Liu, Shuzhao Lan, Jiaqiang Li, Qihong Fang, Yiru Ren, Wei He, Huimin Xie

doi:10.1016/j.tws.2024.112589

极端条件下的数字图像相关

Digital Image Correlation (DIC) has emerged as a pivotal non-contact, full-field deformation measurement method over the past four decades, witnessing a remarkable expansion in its applications across diverse fields. With the rapid progression of cutting-edge science and technologies, the manufacturing and service environments, as well as the scale and characteristics of critical components are advancing toward extremes. There is an urgent necessity to enhance the DIC method to enable the precise capture of mechanical behaviors and principles under extreme conditions. The difficulties, solutions, and applications of DIC in extreme conditions are herein reviewed, together with a discussion of current limitations and future opportunities.

在过去的四十年里，数字图像相关（DIC）已经成为一种关键的非接触、全场变形测量方法，在各个领域的应用都得到了显著的扩展。随着尖端科学技术的快速发展，制造和服务环境以及关键部件的规模和特性正在向极端发展。迫切需要对DIC方法进行改进，以精确捕获极端条件下的力学行为和原理。本文回顾了DIC在极端条件下的困难、解决方案和应用，并讨论了当前的局限性和未来的机会。

Cross-sectional zero-dimension temperature model for thin-walled circular tubes in space environment

Zhe Ma, Zhenxing Shen

doi:10.1016/j.tws.2024.112591

空间环境下薄壁圆管截面零维温度模型

A sufficiently accurate, yet computationally efficient prediction of temperature field is essential for design of spacecraft structures. This paper presents a model dimension reduction method for thermal analysis of thin-walled circular tubes in space environment, which takes into account radiation heat transfer among the internal surfaces besides heat conduction along the circumferential direction and radiative emission from the external surface. Temperature distribution on the tube cross section is approximated by a series of harmonic functions, so that a one-dimensional problem is reduced to that of zero dimension. The relation between average and perturbation temperatures that depend only on time is broadened to fully coupled one. By comparison to the previous model and the plane finite element model, the accuracy and economy of the new model are illustrated. The results show that internal radiation exchange plays an important role in thermal analysis of thin-walled circular tubes used extensively in spacecraft appendages. Furthermore, differences between present and previous models are analyzed and a two-way analysis of variance is performed to determine the effect of various physical and geometric parameters on the temperature distribution and response of the tubes. The work can be further developed to analyze thermally induced deformation and vibration of spacecraft structures.

一个足够精确且计算效率高的温度场预测对于航天器结构设计至关重要。本文提出了空间环境下薄壁圆管热分析的模型降维方法，该方法考虑了薄壁圆管除周向热传导和外表面辐射发射外，内表面之间的辐射换热。用一系列的调和函数来近似管道截面上的温度分布，从而将一维问题简化为零维问题。仅依赖于时间的平均温度和扰动温度之间的关系被扩展为完全耦合的关系。通过与原模型和平面有限元模型的比较，说明了新模型的准确性和经济性。结果表明，内辐射交换在航天器附件中广泛使用的薄壁圆管的热分析中起着重要作用。此外，分析了现有模型与以往模型之间的差异，并进行了双向方差分析，以确定各种物理和几何参数对管道温度分布和响应的影响。这项工作可以进一步发展到分析航天器结构的热致变形和振动。

来源：复合材料力学仿真Composites FEM

【新文速递】2024年10月18日复合材料SCI期刊最新文章

今日更新：Composite Structures 1 篇，Composites Part A: Applied Science and Manufacturing 2 篇，Composites Part B: Engineering 4 篇Composite StructuresEffect of Three-Dimensional auxetic honeycomb core on behavior of sound transmission loss in shallow sandwich cylindrical shellMojtaba Sayad Ghanbari Nezhad, Mehrdad Motavasselolhagh, Roohollah Talebitooti, Fengxian XINdoi:10.1016/j.compstruct.2024.118624三维消声蜂窝芯对浅夹层圆柱壳传声损失特性的影响The primary objective of this research is to examine the sound transmission loss (STL) in a shallow sandwich cylindrical shell featuring a 3D auxetic honeycomb core. Initially, the 3D elasticity theory was employed by applying the state vector method and extracting both local and global transfer matrices to calculate STL relations for the cylindrical shell, including the auxetic honeycomb core. Subsequently, boundary conditions were applied to calculate the unknowns, eventually leading to a relationship for calculating STL within the structure. The derived equations were numerically solved using MATLAB software. The validity of the results obtained using this method was examined by comparing them with the findings of other researchers. Moreover, a comparison was conducted involving a large ratio of the curvature radius to thickness, considering both the auxetic honeycomb core and aluminum with equal mass. The results demonstrate a significant increase in STL when utilizing this auxetic honeycomb core compared to a material with the same mass. Specifically, at a frequency of 2 Hz, a significant enhancement of about 29.44 % in STL is observed when increasing the core thickness from 10.39 mm to 20.39 mm. Furthermore, STL results have been obtained for various thicknesses, radius of curvature, and incident angles.本研究的主要目的是研究具有三维消声蜂窝芯的浅夹层圆柱壳的声传输损失（STL）。首先，采用三维弹性理论，采用状态向量法，提取局部和全局传递矩阵，计算了包括蜂窝芯在内的圆柱壳的STL关系。随后，应用边界条件计算未知数，最终得到计算结构内部STL的关系。利用MATLAB软件对导出的方程进行了数值求解。用这种方法得到的结果的有效性是通过与其他研究人员的发现进行比较来检验的。同时，考虑等质量的铝材和消声蜂窝芯，在曲率半径与厚度之比较大的情况下进行了对比。结果表明，与相同质量的材料相比，使用这种消声蜂窝芯时，STL显著增加。具体来说，在2 Hz频率下，当岩心厚度从10.39 mm增加到20.39 mm时，STL显著增强约29.44 %。此外，还得到了不同厚度、曲率半径和入射角下的STL结果。Composites Part A: Applied Science and ManufacturingThe effect of the Weibull modulus on the shape of the stress–strain curves of thin-ply pseudo-ductile hybrid compositesF. Sheibanian, H. Hosseini-Toudeshky, M. Jalalvand, M.R. Wisnomdoi:10.1016/j.compositesa.2024.108532威布尔模量对薄层伪韧性混杂复合材料应力-应变曲线形状的影响This paper presents a numerical approach using ABAQUS CAE scripting to simulate the mechanical response of thin-ply pseudo-ductile hybrid composites. A parametric study demonstrates that interface critical fracture energy is essential for accurately modeling damage mechanisms and mechanical behavior. Correct shear strength identification enables the model to capture experimental observations, including fragmentation and the plateau region in the stress–strain curve. The analysis shows that the mechanical behavior of these composites is largely independent of fragmentation location patterns in the low-strain layer. Results emphasize the significant impact of the Weibull modulus on the stress–strain response, with careful selection leading to strong correlation with experimental data. Notable differences in best-fit Weibull moduli were observed for different materials, with higher values for high modulus carbon fibers.本文提出了一种利用ABAQUS CAE脚本对薄层伪延性混杂复合材料力学响应进行数值模拟的方法。参数化研究表明，界面临界断裂能是准确模拟损伤机理和力学行为的关键。正确的抗剪强度识别使模型能够捕捉到实验观测结果，包括应力-应变曲线中的破碎和高原区域。分析表明，复合材料的力学行为在很大程度上与低应变层的破碎位置模式无关。结果强调了威布尔模量对应力-应变响应的显著影响，经过精心选择，与实验数据具有较强的相关性。不同材料的最佳拟合威布尔模量存在显著差异，高模量碳纤维的最佳拟合威布尔模量更高。Analysis of rapid decompression failure in polymer liner of Type IV hydrogen storage vessels using a novel fluid–solid coupling modelYitao Li, Zhongmin Xiao, Yanmei Zhang, Weiguo Li, Wengang Zhangdoi:10.1016/j.compositesa.2024.108531基于新型流固耦合模型的IV型储氢容器聚合物内衬快速减压失效分析Type IV vessels have been developed for hydrogen storage systems, but the rapid decompression failure during the decompression process can lead to the collapse of the liner, significantly reducing the lifespan of the vessels. This study aims to investigate nonlinear buckling behaviors and collapse mechanisms of polymer liner in Type IV hydrogen storage vessels. Considering the intrinsic coupling between hydrogen gas depletion and mechanical behavior of vessels, a fluid–solid coupling model was proposed using the fluid cavity techniques and HyperMesh. Results indicated that the pressure difference generated on the liner is the primary cause leading to the polymer liner collapse. The critical pressure difference significantly increases with the thickness of the liner, while it decreases nonlinearly with the increase in void defect size. Parametric sensitivity analysis highlighted the depth of initial void defect and the liner thickness as two significant influencing factors in the critical decompression rate.IV型储氢罐已被开发用于储氢系统，但在减压过程中快速减压失败可能导致衬管坍塌，从而大大降低了储氢罐的使用寿命。本研究旨在研究IV型储氢容器中聚合物衬垫的非线性屈曲行为和坍塌机理。考虑到氢气耗尽与容器力学行为之间的内在耦合，采用流体腔技术和HyperMesh技术建立了容器的流固耦合模型。结果表明，尾管上产生的压差是导致聚合物尾管坍塌的主要原因。临界压差随衬垫厚度的增大而显著增大，随空洞缺陷尺寸的增大而非线性减小。参数敏感性分析表明，初始空洞缺陷深度和衬板厚度是影响临界减压率的两个重要因素。Composites Part B: Engineering“Borrow-force-attack-force” by multi-scale elastic metamaterial with nonlinear dampingChao Zhang, Di Zhang, Fujie Yin, Mingjie Guo, Fuyin Ma, Chengjun Wudoi:10.1016/j.compositesb.2024.111884 具有非线性阻尼的多尺度弹性超材料的“借-力-攻-力”The powerful energy carried by low-frequency vibration is often challenging to be effectively attenuated using traditional damping materials. If low-frequency vibration can be controlled through the energy carried by the excitation itself, the cost of achieving ultra-wide low-frequency vibration control would be significantly reduced. To this end, this paper constructs a multi-scale elastic metamaterial with nonlinear damping (MEMND) to achieve the efficient suppression of ultra-wide low-frequency vibration through its unique transmission characteristics and the effect of “borrow-force-attack-force” (leveraging the excitation to dampen vibration), which is amplified with increasing external excitation. Theoretical, simulation, and experimental results demonstrate that MEMND can achieve over 10 dB damping enhancement at the expense of losing a small amount of the bandgap effect. It exhibits high sensitivity to external excitation in the low-frequency region, offering a promising opportunity for “borrow-force-attack-force”. This work integrates a natural nonlinear damping element into elastic metamaterials and leverages the nonlinear action mechanism of external excitation, presenting a different approach for nonlinear metamaterial design with potential engineering applications.低频振动所携带的强大能量往往难以用传统的阻尼材料有效衰减。如果可以通过激励本身携带的能量来控制低频振动，那么实现超宽低频振动控制的成本将大大降低。为此，本文构建了一种具有非线性阻尼的多尺度弹性超材料（MEMND），利用其独特的传输特性和“借-力-攻-力”（利用激励来抑制振动）的效果，并随着外部激励的增加而放大，从而实现对超宽低频振动的有效抑制。理论、仿真和实验结果表明，MEMND可以在损失少量带隙效应的情况下实现10 dB以上的阻尼增强。它在低频区域对外部激励具有很高的灵敏度，为“借-力-攻-力”提供了很好的机会。本研究将自然非线性阻尼元件集成到弹性超材料中，并利用外部激励的非线性作用机制，为具有潜在工程应用价值的非线性超材料设计提供了一种不同的方法。Cartilage regeneration achieved in photo-crosslinked hyaluronic hydrogel bioactivated by recombinant humanized collagen type IIIYang Xu, Jing Wang, Zhanhong Liu, He Qiu, Lu Song, Shuo Liu, Yajun Tang, Lu Chen, Xing Ma, Kai Zhang, Hai Lin, Xingdong Zhangdoi:10.1016/j.compositesb.2024.111886 重组人源ⅲ型胶原生物活化光交联透明质水凝胶实现软骨再生Collagen has been extensively investigated as a bioactive material in cartilage tissue engineering. Recombinant humanized collagen type III (rhCol III) possessed excellent biocompatibility and imperative interactions with various cells shows a significant advantage as the starting material of medical devices. To investigate the bioactivation effect of rhCol III in cartilage tissue engineering, methacrylated hyaluronic acid (HA-MA) was prepared and rhCol III was further compounded to establish a photo-crosslinked composite hydrogel (HA-rhCol Ⅲ) platform to study the cartilage regeneration with chondrocytes encapsulated. The results verified that the HA-rhCol III hydrogels could be rapidly formed with stable mechanical properties using the blue light curing system. Meanwhile, the rhCol III could be effectively retained inside the composite hydrogel, which was conducive to maintain its bioactive function for a longer period. In vitro cell experiments confirmed that rhCol III improved the local microenvironment for chondrocytes, which provided abundant adhesion sites and further promoted cell migration, proliferation and differentiation. In vivo results indicated that the composite hydrogels could be conveniently applied to fulfill the cartilage defect in rabbit, and the histological and immunohistological results suggested that cartilage regeneration could be achieved with the application of HA-rhCol Ⅲ composite hydrogels. It could be concluded that the addition of rhCol III could bioactivate the hydrogel and promote the tissue regeneration, showing potential for application in tissue engineering.胶原蛋白作为一种生物活性材料在软骨组织工程中得到了广泛的研究。重组人源化III型胶原具有良好的生物相容性和与多种细胞的良好相互作用，作为医疗器械的起始材料具有显著的优势。为了研究rhCol III在软骨组织工程中的生物活化作用，制备甲基丙烯酸透明质酸（HA-MA），进一步复配rhCol III，建立光交联复合水凝胶（HA-rhColⅢ）平台，研究软骨细胞包封后的软骨再生。结果表明，蓝光固化体系可以快速形成具有稳定力学性能的HA-rhCol III水凝胶。同时，rhCol III能有效保留在复合水凝胶内部，有利于较长时间保持其生物活性功能。体外细胞实验证实，rhCol III改善了软骨细胞的局部微环境，提供了丰富的粘附位点，进一步促进了细胞的迁移、增殖和分化。体内实验结果表明，复合水凝胶可以方便地用于兔软骨缺损的修复，组织学和免疫组织学结果表明，HA-rhColⅢ复合水凝胶可以实现软骨的再生。由此可见，rhCol III的加入对水凝胶具有生物活化作用，促进了组织再生，在组织工程中具有应用潜力。Enhancing interfacial locking of the CF and PBPESK resin by in-situ electrochemical deposition of MOF nanoparticlesWenqi Zhao, Hang Jia, Yue Qiao, Yu Zhang, Junyi Wu, Xigao Jian, Cheng Liudoi:10.1016/j.compositesb.2024.111888 原位电化学沉积MOF纳米颗粒增强CF和PBPESK树脂的界面锁定The interfacial bonding of carbon fiber reinforced polymer composites plays a critical role in the overall performance of the composites. Poor interfacial bonding leads to catastrophic damage of composites when subjected to external loads. In this study, three-dimensional (3D) NH2-UiO-66 nanoparticles in-situ synthesis on the carbon fiber (CF) surface using an electrochemical method was achieved facilely and efficiently to enhance the interfacial adhesion of CF/PBPESK composites. The influence of incorporating 3D NH2-UiO-66 nanoparticles into the interphase on the interfacial and mechanical properties of carbon fiber reinforced composites was systematically investigated. The NH2-UiO-66 nanoparticles significantly increased the carbon fibers surface energy. The flexural, interlaminar shear and interfacial shear strength of the N–CF–6min/PBPESK composite were improved by 19 %, 31 %, and 93 %, respectively, compared to the D-CF/PBPESK composite. Furthermore, the interfacial failure mechanism of the composites was investigated. This approach offered a simple and efficient strategy for the in-situ synthesis of interfacial phase characterized by robust mechanical locking effects.碳纤维增强聚合物复合材料的界面结合对复合材料的整体性能起着至关重要的作用。当复合材料受到外部载荷时，界面粘结不良会导致材料的灾难性损伤。在本研究中，采用电化学方法在碳纤维（CF）表面原位合成了三维（3D） NH2-UiO-66纳米颗粒，以增强CF/PBPESK复合材料的界面附着力。系统研究了界面相中加入三维NH2-UiO-66纳米颗粒对碳纤维增强复合材料界面性能和力学性能的影响。NH2-UiO-66纳米颗粒显著提高了碳纤维的表面能。与D-CF/PBPESK复合材料相比，N-CF-6min /PBPESK复合材料的弯曲强度、层间剪切强度和界面剪切强度分别提高了19%、31%和93%。进一步研究了复合材料的界面破坏机理。该方法为原位合成具有较强机械锁定效应的界面相提供了一种简单有效的方法。Density Gradient Structure Foams Prepared by Novel Two-step Foaming Strategy: Performance, Simulation and OptimizationXingyu Jia, Wenyu Zhong, Yichong Chen, Dongdong Hu, Jiayang Sun, Yao Peng, Jiabao Yu, Xiulei Jiang, Ling Zhaodoi:10.1016/j.compositesb.2024.111890新型两步发泡策略制备密度梯度结构泡沫：性能、模拟与优化Functional gradient foam materials play a crucial role in meeting the diverse performance and functionality requirements of modern engineering. Density gradients enable the distribution of mechanical, dielectric, and optical properties within materials, exhibiting a gradient representation. However, creating density gradients within foams poses a significant challenge, especially for semi-crystalline polymers. The paper proposed a novel two-step foaming method for preparing polypropylene (PP) foams with density gradient structure (DGS). Initially, a pre-foaming process was conducted to prepare PP pre-foams with uniform structure (US) at low temperatures, followed by a secondary foaming process on partially saturated PP pre-foams to fabricate PP DGS foams. By adjusting the duration of partial saturation time, PP foams with various DGS can be achieved. Compared with the commonly used one-step foaming method and uniform foaming method in the literature, the DGS foams prepared by the two-step foaming method exhibit not only a significant enhancement in mechanical property but also achieve the lowest thermal conductivity, while maintaining comparable and outstanding sound insulation performance. Finally, a comprehensive evaluation model using COMSOL Multiphysics was developed for the DGS foams, providing insights for optimizing foam performance through process enhancements.功能梯度泡沫材料在满足现代工程对各种性能和功能的要求方面起着至关重要的作用。密度梯度使材料内部的机械、介电和光学特性分布成为可能，呈现出梯度表示。然而，在泡沫中产生密度梯度是一个重大挑战，特别是对于半结晶聚合物。提出了一种制备密度梯度结构（DGS）聚丙烯（PP）泡沫的新型两步发泡方法。首先采用低温预发泡法制备结构均匀（US）的PP预泡沫，然后在部分饱和的PP预泡沫上进行二次发泡法制备PP DGS泡沫。通过调整部分饱和时间的长短，可以得到具有不同DGS的PP泡沫。与文献中常用的一步发泡法和均匀发泡法相比，两步发泡法制备的DGS泡沫不仅力学性能显著增强，而且导热系数最低，同时保持了相当优异的隔声性能。最后，利用COMSOL Multiphysics为DGS泡沫开发了一个综合评估模型，为通过工艺改进优化泡沫性能提供了见解。来源：复合材料力学仿真Composites FEM