Materials & Design最新文献_第7页

Study on the mechanical properties of Yili loess improved by EICP biomimetic mineralization technology under freeze-thaw cycle conditions 冻融循环条件下EICP仿生矿化技术改良伊犁黄土力学特性研究

IF 7.9 2区材料科学 Q1 MATERIALS SCIENCE, MULTIDISCIPLINARY

Materials & Design

Pub Date : 2026-03-01 Epub Date: 2026-01-27 DOI: 10.1016/j.matdes.2026.115574

Guangming Shi , Yuan Xue , Dejun Yang , Ai Zhang , Weiming Guan , Junhui Zhang , Xinhui Pan , Dingyu Wang , Chao Jin

This study employs Enzyme-Induced Carbonate Precipitation (EICP) technology on Yili loess to enhance its resistance to freeze–thaw damage. EICP significantly improves the durability of the loess by restricting moisture migration and alleviating stresses induced by ice crystal formation. Following 15 freeze–thaw cycles, specimens treated with EICP exhibited only minor surface cracks, in stark contrast to the extensive crack networks observed in untreated specimens. In terms of mechanical properties, the EICP-treated loess demonstrated a 1.5-fold increase in unconfined compressive strength and a 1.33-fold rise in initial elastic modulus, maintaining advantages of 1.6-fold and 2.2-fold, respectively, after undergoing the cycles. The failure mode shifted from shear to compression, indicating enhanced structural integrity. Under the combined effects of freeze–thaw action and confining pressure, the shear strength of the treated loess consistently remained higher, primarily due to an increase in cohesion (1.17-fold initially and 18.72% higher after cycling), while the friction angle exhibited minimal change. Scanning Electron Microscope (SEM) observations revealed that calcium carbonate cementation filled the pores, resulting in a dense structure dominated by small- to medium-sized pores, effectively suppressing pore expansion and crack propagation induced by freeze–thaw cycles. This research showcases a promising technique for stabilizing Yili loess in cold regions.

采用酶促碳酸盐沉淀（EICP）技术对伊犁黄土进行抗冻融损伤处理。EICP通过限制水分迁移和减轻冰晶形成引起的应力显著提高黄土的耐久性。经过15次冻融循环后，经EICP处理的试件只有轻微的表面裂缝，与未经处理的试件中观察到的广泛的裂缝网络形成鲜明对比。力学性能方面，经过循环处理的黄土无侧限抗压强度和初始弹性模量分别提高了1.5倍和1.33倍，保持了分别为1.6倍和2.2倍的优势。破坏模式由剪切转变为压缩，结构完整性增强。在冻融和围压共同作用下，处理后黄土的抗剪强度保持较高，主要是由于黏聚力增加（初始增加1.17倍，循环后增加18.72%），而摩擦角变化不大。扫描电镜（SEM）观察发现，孔隙中存在碳酸钙胶结，形成以中小孔隙为主的致密结构，有效抑制冻融循环引起的孔隙扩张和裂纹扩展。本研究为寒区伊犁黄土的稳定提供了一种有前景的技术。

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引用次数: 0

Sodium periodate-driven one pot iodine doping TiO2 for superior visible-light photocatalytic degradation 高碘酸钠驱动的一锅碘掺杂TiO2具有优越的可见光催化降解性能

IF 7.9 2区材料科学 Q1 MATERIALS SCIENCE, MULTIDISCIPLINARY

Materials & Design

Pub Date : 2026-03-01 Epub Date: 2026-01-30 DOI: 10.1016/j.matdes.2026.115585

Min Yao , Zhida Liu , Weizhang Guo , Guanzheng Wu , Dawei Gao , Gaopeng Jia , Huanling Wu , Ling Lin , Yu Ren , Zhengming Qi , Chunxia Wang

Visible light driven photocatalysis offers a sustainable solution for environmental remediation. As a cornerstone photocatalyst, the practical application of TiO₂ is severely constrained by its narrow visible light response range and inefficient charge carrier separation. An innovative one-pot synthesis strategy was developed for preparing a highly active iodine-doped TiO₂ (I-TiO₂) visible light photocatalyst, using NaIO₄′s dual functionality as simultaneous iodine source and oxidant. Characterization revealed that the successful iodine doping in TiO₂ matrix effectively reduced bandgap energy and suppressed charge carrier recombination, consequently broadening optical absorption range and enhancing visible light responsiveness. The prepared anatase I-TiO₂ exhibited small crystallite of 6.93 nm and high surface area of 222.61 m²/g. The optimized I-TiO₂ achieved 99.04 % and 89.65 % degradation efficiency of methylene orange (MO) solution within 10 min and 60 min, while maintaining 92.6 % and 85.1 % after consecutive three recycling tests under simulated sunlight and visible light, respectively, demonstrating its superior photocatalytic activity and stability. Active species trapping experiment and ESR analysis revealed that superoxide radicals (⋅O₂⁻) served as the dominant active species in I-TiO₂ photocatalytic degradation process of MO solution. This work provides new insights into oxidant-assisted doping strategies for designing high-performance visible light photocatalysts.

可见光驱动的光催化为环境修复提供了一个可持续的解决方案。TiO2作为光催化剂的基石，其可见光响应范围窄，载流子分离效率低，严重制约了其实际应用。利用NaIO4的双重功能同时作为碘源和氧化剂，提出了一种创新的一锅合成策略，制备了高活性的碘掺杂TiO2 （I-TiO2）可见光催化剂。表征表明，在TiO2基体中成功掺杂碘能有效降低带隙能量，抑制载流子复合，从而拓宽光吸收范围，增强可见光响应性。制备的锐钛矿I-TiO2微晶尺寸为6.93 nm，比表面积为222.61 m2/g。优化后的I-TiO2在10 min和60 min内对亚甲基橙（MO）溶液的降解效率分别达到99.04%和89.65%，在模拟日光和可见光下连续三次循环测试后，降解效率分别保持在92.6%和85.1%，显示出优异的光催化活性和稳定性。活性物质捕获实验和ESR分析表明，超氧自由基（⋅O2−）是I-TiO2光催化降解MO溶液过程中的优势活性物质。这项工作为设计高性能可见光催化剂提供了氧化剂辅助掺杂策略的新见解。

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引用次数: 0

Improvement of transmittance homogeneity via coating anti-Gaussian chromium films on tapered optical fibre arrays 在锥形光纤阵列上涂覆抗高斯铬膜以改善透过率均匀性

IF 7.9 2区材料科学 Q1 MATERIALS SCIENCE, MULTIDISCIPLINARY

Materials & Design

Pub Date : 2026-03-01 Epub Date: 2026-02-11 DOI: 10.1016/j.matdes.2026.115648

Yuwen Xing , Juan Liu , Yonggang Huang , Peng Jiao , Yajie Du , Weiwei Cao , Pan Shi , Le Chang , Zhili He , Jinsheng Jia

The transmittance inhomogeneity of Tapered Optical Fibre Arrays (TOFAs) is well-recognized to attenuate edge signal, reduce detective sensitivity and compress dynamic response range. A radial depth-varied coating scheme based on a ‘transmittance-film thickness’ digital correlation model was proposed to improve the transmittance inhomogeneity of TOFA. Considering the characteristic that TOFAs exhibit a Gaussian distribution in their inherent transmittance, a volute mask with spiral gradient openings was first designed. This mask was then integrated with a self-developed rotating coating device to build a dynamically coordinated deposition system. The anti-Gaussian films was successfully fabricated by the integrated depositing system. The microscopic characterization by TEM and SEM illustrates the nonlinear and precise control on the thickness of the metallic chromium film from the center to the edge. The experimental results show the transmittance inhomogeneity of TOFAs coated by anti-Gaussian film is decreased from originally ranging from 4.21% to 11.872% to a minimum of 1.422%. It is confirmed that the prepared high-quality anti-Gaussian film effectively compensate transmittance.

锥形光纤阵列的透光率不均匀性对边缘信号的衰减、探测灵敏度的降低和动态响应范围的压缩具有重要的作用。为了改善TOFA的透光率不均匀性，提出了一种基于“透光率-膜厚”数字相关模型的径向变深涂层方案。考虑tofa固有透过率呈高斯分布的特点，设计了螺旋梯度开口的蜗壳掩模。然后将该掩膜与自行开发的旋转镀膜装置集成在一起，构建动态协调的沉积系统。采用集成沉积系统成功制备了反高斯薄膜。TEM和SEM的微观表征表明，金属铬膜的厚度从中心到边缘呈非线性精确控制。实验结果表明，经反高斯膜涂层的tofa的透过率不均匀性由原来的4.21% ~ 11.872%降低到最小的1.422%。结果表明，制备的高质量抗高斯膜能有效地补偿透光率。

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引用次数: 0

Effect of carbon content on solidification behavior of a Mo- and Al-rich nickel-based single-crystal superalloy 碳含量对富Mo和富al镍基单晶高温合金凝固行为的影响

IF 7.9 2区材料科学 Q1 MATERIALS SCIENCE, MULTIDISCIPLINARY

Materials & Design

Pub Date : 2026-03-01 Epub Date: 2026-02-05 DOI: 10.1016/j.matdes.2026.115601

Xiaoyu Song , Shusuo Li , Haigen Zhao , Wenqi Guo , Yi Ru , Tianyu Zhang , Weitao Xu , Shan Li , Bin Gan , Yanling Pei , Shengkai Gong

Optimizing carbon content is critical for the design of Ni-based single-crystal superalloys, particularly for high-temperature applications. This study systematically investigated the influence of carbon on the solidification behavior and phase evolution of a Mo- and Al-rich Ni-based single-crystal superalloy. Increasing carbon content lowered the solidus temperature and widened the mushy zone, which is associated with the precipitation of low-melting-point carbides during the terminal stage of solidification. At 56 ppm carbon, no carbides were observed and the interdendritic regions contained the σ-NiMoRe phase with a tetragonal structure. At 180 ppm carbon, σ-NiMoRe and blocky primary M₆C carbides coexisted adjacent to the large primary blocky γ′ phase, separated by distinct boundaries. At 270 ppm carbon, script-like, Mo- and Ta-enriched M₆C carbides with a cubic (fcc-type) structure became the dominant interdendritic constituent; concurrently, elemental segregation became more pronounced. Increasing carbon content also increased the secondary dendrite arm spacing (SDAS) and reduced both the liquid viscosity (μ) and solidification shrinkage coefficient (β). These effects contributed to significant porosity reduction by decreasing the shrinkage pressure drop. Overall, controlled carbon addition optimizes solidification behavior and phase stability, providing practical guidance for alloy design and solidification control in Mo- and Al-rich Ni-based single-crystal superalloys.

优化碳含量对镍基单晶高温合金的设计至关重要，特别是在高温应用中。本研究系统地研究了碳对一种富含Mo和al的ni基单晶高温合金凝固行为和相演化的影响。随着碳含量的增加，固相温度降低，糊化区变宽，这与凝固后期低熔点碳化物的析出有关。在碳含量为56 ppm时，未观察到碳化物的存在，枝晶间区含有具有四方结构的σ-NiMoRe相。在180 ppm时，σ-NiMoRe和块状初生M6C碳化物共存于较大的初生块状γ′相附近，并有明显的边界分隔。在270 ppm碳浓度下，具有立方（fcc型）结构的脚本状、富含Mo和ta的M6C碳化物成为枝晶间的主要成分；同时，元素分离变得更加明显。碳含量的增加增加了二次枝晶臂间距（SDAS），降低了液体粘度（μ）和凝固收缩系数（β）。这些效果通过降低收缩压降来显著降低孔隙率。总体而言，可控加碳优化了凝固行为和相稳定性，为富Mo和富al镍基单晶高温合金的合金设计和凝固控制提供了实用指导。

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引用次数: 0

Enhancing the mechanical properties of Mg-7Li-3Zn-3Gd alloy by Extrusion-Swaging based on elemental segregation 基于元素偏析的挤压-挤压成形提高Mg-7Li-3Zn-3Gd合金力学性能

IF 7.9 2区材料科学 Q1 MATERIALS SCIENCE, MULTIDISCIPLINARY

Materials & Design

Pub Date : 2026-03-01 Epub Date: 2026-01-27 DOI: 10.1016/j.matdes.2026.115571

Ruihao Fu , Zihao Zhou , Yan Yang , Chenwei Hu , Yuyang Gao , Di Pei , Qiang Yang , Qian Li , Bin Jiang

A lightweight, high-strength, and ductile Mg-7Li-3Zn-3Gd alloy was fabricated through a two-stage mechanical processing route: initial hot-extrusion followed by room-temperature rotary swaging. The primary reinforcement mechanism of the test alloys had been investigated, with the following results. The yield strength, tensile strength and elongation of the Mg-7Li-3Zn-3Gd alloy at room temperature reach to 276 MPa, 303 MPa and 24%, respectively. The alloy mainly consisted of α-Mg, β-Li, Mg₃Zn₃Gd₂ and MgZn₂ phases. Dynamic precipitation and dynamic recrystallization occurred during hot extrusion. In the rotary-swaged alloy, precipitates dispersed and pinned the grain boundaries, refined the grains and hindered the dislocation movement. The Zn element segregated around Mg₃Zn₃Gd₂ and MgZn₂, stabilizing the interfaces and the intermetallic phases. The segregation of zinc further increased the radius of dislocation barriers, and improved performance. Notably, nanosized precipitates and element segregation synergistically regulated the mechanical properties of the Mg-7Li-3Zn-3Gd alloy.

采用初始热挤压和室温旋锻两阶段的工艺路线制备了轻量化、高强、延展性好的Mg-7Li-3Zn-3Gd合金。研究了试验合金的初强化机理，得到了以下结果：Mg-7Li-3Zn-3Gd合金的室温屈服强度、抗拉强度和延伸率分别达到276 MPa、303 MPa和24%。合金主要由α-Mg、β-Li、Mg3Zn3Gd2和MgZn2相组成。热挤压过程中发生动态析出和动态再结晶。在旋转锻压合金中，析出相分散，固着晶界，细化晶粒，阻碍位错运动。锌元素在Mg3Zn3Gd2和MgZn2周围析出，使界面和金属间相稳定。锌的偏析进一步增大了位错势垒半径，提高了性能。纳米析出相和元素偏析协同调节Mg-7Li-3Zn-3Gd合金的力学性能。

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引用次数: 0

Cellulose-inspired anisotropic hydrogen bond-enhanced strong and tough poly(vinyl alcohol)-chitosan hydrogel for chronic wound healing 纤维素激发的各向异性氢键增强强韧性聚乙烯醇-壳聚糖水凝胶用于慢性伤口愈合

IF 7.9 2区材料科学 Q1 MATERIALS SCIENCE, MULTIDISCIPLINARY

Materials & Design

Pub Date : 2026-03-01 Epub Date: 2026-01-30 DOI: 10.1016/j.matdes.2026.115591

Haixu Li , Xiaolei Wang , Yagan Duan , Tingting Wu , Xinrui Guo , Tianyu Zhang , Zhuoheng Li , Wenxin Cao , Jiaqi Zhu , Yu Sun

This study proposes a cellulose-biomimetic structural strategy and employs a composite process of directional freezing and salt precipitation to successfully fabricate a hydrogen-bond-enhanced anisotropic Poly(vinyl alcohol)₅-chitosan hydrogel₁ (P₅-CS₁). This hydrogel exhibits a tensile strength of 8.6 MPa (≈33-fold higher than that of P₅-CS₁-FT prepared via the freeze–thaw method) and a toughness of 29.1 ± 1.4 MJ/m³ (≈80-fold higher than that of the P₅-CS₁-FT). This hydrogel simultaneously achieves strain (713%), water content (77%), and porosity (82%). While its water content matches that of human tissues, its tensile properties outperform typical PVA-based wound dressings and even surpass those of natural tissues (e.g., muscle and cartilage). To adapt to diverse chronic wound scenarios, phosphorylated chitosan (PCS) is incorporated to form P₅-CS₁-P. In vitro and in vivo experiments confirm that P₅-CS₁-P exhibits robust bioactivity, maintaining > 100% L929 viability, reducing IL-1 and IL-6, and accelerating SD rat full-thickness wound closure to 95%. The design integrates physical protection, directional fluid management, and drug delivery, while PCS loading adds anti-inflammatory, antibacterial, and pro-healing functions, offering a promising synergistic strategy for chronic wound care.

本研究提出了纤维素仿生结构策略，采用定向冷冻和盐沉淀复合工艺成功制备了氢键增强的各向异性聚乙烯醇5-壳聚糖水凝胶（P5-CS1）。该水凝胶的抗拉强度为8.6 MPa（比冻融法制备的P5-CS1-FT高约33倍），韧性为29.1±1.4 MJ/m3（比P5-CS1-FT高约80倍）。该水凝胶可同时实现应变（713%）、含水量（77%）和孔隙率（82%）。虽然其含水量与人体组织相匹配，但其拉伸性能优于典型的pva基伤口敷料，甚至超过天然组织（如肌肉和软骨）。为了适应不同的慢性创伤情况，磷酸化壳聚糖（PCS）被掺入形成P5-CS1-P。体外和体内实验证实P5-CS1-P具有强大的生物活性，可维持100%的L929活力，降低IL-1和IL-6，并可使SD大鼠全层创面愈合加速至95%。该设计集成了物理保护、定向流体管理和药物输送，而PCS负载增加了抗炎、抗菌和促愈合功能，为慢性伤口护理提供了有前途的协同策略。

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引用次数: 0

Grinding force reduction mechanism for micro-dimple morphology in ultrasonic-assisted longitudinal-normal grinding 超声辅助纵法向磨削中微韧窝形貌的磨削力减小机制

IF 7.9 2区材料科学 Q1 MATERIALS SCIENCE, MULTIDISCIPLINARY

Materials & Design

Pub Date : 2026-03-01 Epub Date: 2026-01-27 DOI: 10.1016/j.matdes.2026.115565

Jiaying Han , Lijia Zhang , Xinrong Zhang , Yahui Hu

To meet the surface quality requirements of steel-based materials in high-precision machining, this study employs a tapered wheel to convert one-dimensional (1D) longitudinal ultrasonic vibration into two-dimensional (2D) longitudinal-normal coupled vibrations in a rotary ultrasonic-assisted grinding (RUAG) system. This method effectively produces a novel “non-contact intermittent grinding” behavior in abrasive grains, which reduces grinding forces and facilitates the formation of micro-dimples. To study the reduction mechanism of grinding force, a theoretical force prediction model of a single grain was proposed, which extended the framework of cutting deformation and friction forces by incorporating an impact force component. Systematic investigations revealed that grinding forces increased with vibration amplitude, decreased with rotational speed, and sharply rose with feed rate. Model predictions showed an error rate of less than 15% compared to experimental results. Experimental results of eccentric grinding wheel further confirmed that the frequent occurrence of non-contact grinding increased effective grain engagement, significantly reduced grinding depth and forces, and improved surface roughness compared to conventional grinding (CG) methods. This study provides theoretical models, simulated approaches, and practical guidelines for advancing 2D ultrasonic grinding technologies, with implications for enhanced precision and efficiency in industrial applications.

为了满足钢基材料在高精度加工中的表面质量要求，在旋转超声辅助磨削（RUAG）系统中，采用锥轮将一维（1D）纵向超声振动转化为二维（2D）纵向-法向耦合振动。该方法有效地在磨料颗粒中产生了一种新的“非接触间歇磨削”行为，减少了磨削力，促进了微韧窝的形成。为了研究磨削力的减小机理，提出了一种单晶粒的理论力预测模型，该模型通过加入冲击力分量扩展了切削变形和摩擦力的框架。系统研究表明，磨削力随振动幅值的增大而增大，随转速的增大而减小，随进给量的增大而急剧增大。与实验结果相比，模型预测的错误率小于15%。偏心砂轮的实验结果进一步证实，与常规磨削（CG）方法相比，频繁的非接触磨削增加了有效晶粒啮合，显著降低了磨削深度和磨削力，改善了表面粗糙度。本研究为推进二维超声磨削技术提供了理论模型、仿真方法和实践指导，对提高工业应用的精度和效率具有重要意义。

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引用次数: 0

MMP-responsive hydrogel: a new approach for tissue repair and regeneration mmp反应水凝胶：组织修复和再生的新途径

IF 7.9 2区材料科学 Q1 MATERIALS SCIENCE, MULTIDISCIPLINARY

Materials & Design

Pub Date : 2026-03-01 Epub Date: 2026-01-29 DOI: 10.1016/j.matdes.2026.115573

Yue Sun , Ming Sun , Xingyu Lin , Yifei Sun , Dongmei Mei , Hui Zhang , Fan Li , Shujie Wang

Tissue injury can lead to structural and functional abnormalities, severely impacting health-related quality of life. Due to the complex dynamics of the tissue injury microenvironment, traditional hydrogels struggle to achieve real-time drug release regulation tailored to disease progression. Given that matrix metalloproteinases (MMPs) exhibit highly specific and significant changes within this microenvironment, MMP-responsive hydrogels have been designed to recognize pathologically overexpressed MMPs, enabling spatiotemporal-controlled drug release and remodeling of the injury microenvironment. Additionally, the three-dimensional network structure of hydrogels not only provides a scaffold for cell migration and proliferation but also effectively fills irregular tissue defects, thus overcoming the mechanical support limitations of nanocarriers. This review systematically summarizes the multi-scale design strategies of MMP-responsive hydrogels, including their composition designs, synthetic methods, and drug loading strategies, while delving into their mechanisms of action in wound healing, bone/cartilage repair, myocardial regeneration, and neural repair. Furthermore, we analyze the current opportunities and challenges in clinical translation, providing insights for developing next-generation intelligent hydrogels.

组织损伤可导致结构和功能异常，严重影响与健康相关的生活质量。由于组织损伤微环境的复杂动态，传统的水凝胶难以实现针对疾病进展的实时药物释放调节。鉴于基质金属蛋白酶（MMPs）在这种微环境中表现出高度特异性和显著的变化，mmp响应水凝胶被设计用于识别病理过表达的MMPs，从而实现时空控制的药物释放和损伤微环境的重塑。此外，水凝胶的三维网络结构不仅为细胞迁移和增殖提供了支架，而且可以有效地填充不规则的组织缺陷，从而克服了纳米载体的机械支持局限性。本文系统总结了mmp反应性水凝胶的多尺度设计策略，包括其组成设计、合成方法和载药策略，并深入探讨了其在伤口愈合、骨/软骨修复、心肌再生和神经修复中的作用机制。此外，我们还分析了目前临床翻译中的机遇和挑战，为开发下一代智能水凝胶提供了见解。

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引用次数: 0

Design and validation of Offset Split-P porous titanium implants for mandibular defect repair 偏置Split-P多孔钛种植体修复下颌骨缺损的设计与验证

IF 7.9 2区材料科学 Q1 MATERIALS SCIENCE, MULTIDISCIPLINARY

Materials & Design

Pub Date : 2026-03-01 Epub Date: 2026-01-21 DOI: 10.1016/j.matdes.2026.115533

Yi Lu , Zhe Chen , Qiulong chen , Bin Wu , Bin Yan , Min Chen , Fei Jiang , Yuhuan Xiao , Fan Yang , Jing Rao , Samir Mustapha , Jianhua Li

Mandibular defects from tumor resection and trauma are increasing, while autograft and allograft resources remain limited. Here, we developed and fabricated a mandibular implant based on an offset-optimized, gradient-designed Split-P lattice. The feasibility of the porous implant was systematically assessed through mechanical simulations, fluid dynamic analyses, compression testing, in vitro cell culture, and corrosion immersion experiments, employing small-scale Ti-6Al-4V Offset Split-P structures (unit cell: 5 × 5 × 5 mm; strut diameter: 0.5 mm). The results demonstrate that this structure exhibits superior mass transport performance compared with four common topologies (Gyroid, Schwarz, Diamond, and Neovius). At porosities consistent with the human mandible (60 %–90 %), its elastic modulus (3.83–18.89 GPa) and yield strength (28.51–171.90 MPa) that match the characteristic range of human mandibular bone, while maintaining good biocompatibility. Moreover, it promotes cell proliferation, directional migration, and osteogenic differentiation, and shows outstanding corrosion resistance, ensuring long-term structural stability.

肿瘤切除和创伤导致的下颌缺损越来越多，而自体和同种异体移植资源仍然有限。在这里，我们开发并制造了一个基于偏移优化，梯度设计的Split-P晶格的下颌种植体。通过力学模拟、流体动力学分析、压缩测试、体外细胞培养和腐蚀浸泡实验，系统评估了多孔植入物的可行性，采用小型Ti-6Al-4V偏置splt - p结构（单元胞：5 × 5 × 5 mm；支撑直径：0.5 mm）。结果表明，与四种常见拓扑（Gyroid、Schwarz、Diamond和Neovius）相比，这种结构具有优越的质量传输性能。在孔隙率与人类下颌骨一致（60% ~ 90%）的情况下，其弹性模量（3.83 ~ 18.89 GPa）和屈服强度（28.51 ~ 171.90 MPa）符合人类下颌骨的特征范围，同时保持良好的生物相容性。此外，它还促进细胞增殖、定向迁移和成骨分化，并表现出出色的耐腐蚀性，确保了长期的结构稳定性。

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引用次数: 0

Effect of post-weld heat treatment on microstructure and hydrogen embrittlement of stir zone of friction stir welded 2xxx aluminum-alloy joints 焊后热处理对2xxx铝合金搅拌摩擦焊接接头搅拌区组织及氢脆的影响

IF 7.9 2区材料科学 Q1 MATERIALS SCIENCE, MULTIDISCIPLINARY

Materials & Design

Pub Date : 2026-03-01 Epub Date: 2026-01-19 DOI: 10.1016/j.matdes.2026.115517

Xiaogang Li , Junfeng Nie , Yong Liu , Xu Zhang , Haiquan Zhang

Stir zone was weakest constituent of friction stir welded (FSW) aluminum-alloy joints, however, hydrogen embrittlement on the isolated stir zone has not been clarified. Here, effect of post-weld heat treatment (PWHT) on the microstructure and hydrogen embrittlement of the stir zone of FSW 2xxx aluminum-alloy joints is investigated by electrochemical hydrogen charging, tensile tests and advanced micro-characterization methods. Samples of stir zones extracted from the as-welded FSW joint and PWHT FSW joint are labeled sample A and sample B, respectively. Pristine sample A contains very few θ precipitates. PWHT causes abundant θ′ phase re-precipitation in sample B, following a (0 0 1)_θ′//(0 01 )_α-Al and [1 0 0]_θ′//[1 0 0]_α-Al orientation relationship. After PWHT, the tensile strength of stir zone could be increased by 9%, accompanied by the decrease in the plasticity, which is attributed to the dislocation movement obstruction and dislocation accumulation caused by θ′ phases. Notably, hydrogen embrittlement sensitivity index by tensile strength was 13.9% for sample B, much higher than that for sample A because of θ′ phase re-precipitation in the stir zone. Abundant θ′ precipitates in sample B obstruct dislocation movement, cause dislocation pile-ups, and function as hydrogen-trap sites enabling hydrogen-atom accumulation, leading to significant hydrogen embrittlement failure triggered by hydrogen-enhanced local plasticity.

搅拌区是搅拌摩擦焊铝合金接头中最弱的组成部分，但对搅拌区氢脆的研究尚不明确。通过电化学充氢、拉伸试验和先进的微观表征方法，研究了焊后热处理对fsw2xxx铝合金接头搅拌区微观组织和氢脆的影响。从焊接状态FSW接头和PWHT FSW接头中提取的搅拌区样品分别标记为样品A和样品B。原始样品A含有很少的θ沉淀。PWHT导致样品B中大量的θ′相再沉淀，遵循(0 01)θ′//(0 01)α-Al和[1 0 0]θ′//[1 0 0]α-Al取向关系。PWHT后，搅拌区的抗拉强度可提高9%，但塑性下降，这是由于θ′相阻碍位错运动和位错积累所致。值得注意的是，试样B的抗拉强度氢脆敏感性指数为13.9%，远高于试样A，原因是搅拌区θ′相的再析出。样品B中大量的θ′沉淀阻碍了位错的运动，导致位错堆积，并作为氢原子聚集的氢阱位点，导致氢增强的局部塑性引发明显的氢脆破坏。

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引用次数: 0