今日更新:Composite Structures 9 篇,Composites Part A: Applied Science and Manufacturing 3 篇,Composites Part B: Engineering 2 篇
Influence of fatigue damage on the impact performance of toughened-interleave carbon fibre epoxy composite laminates
D. Thomson, D.E. Sommer, G. Quino, O. Falcó, N. Petrinic
doi:10.1016/j.compstruct.2024.118345
疲劳损伤对增韧间隙碳纤维环氧复合材料层压板冲击性能的影响
The impact performance of mechanically fatigued carbon fibre-reinforced polymer (CFRP) composite laminates with and without thermoplastic toughening particles has been investigated through a joint experimental and numerical campaign. Prismatic carbon fibre/epoxy specimens with added toughening particles at the ply interfaces were mechanically fatigued with different load amplitudes leading to a loss in apparent stiffness of 10% to 15%. Following the fatigue loading, high resolution computed tomography (CT) has been performed, revealing varying degrees of delamination starting from the free edges along the length of the specimens. In addition, transverse matrix cracks are observed in all fatigued specimens regardless of the amount of delamination. The residual ballistic impact performance of the damaged specimens has been investigated in a dynamic three-point bending configuration at three different velocities, showing a significant detrimental effect of even barely visible initial delamination. In addition, post-mortem CT scans and detailed finite element simulations are used to gain further insight into the mechanisms by which the two types of initial damage affected the impact resistance of the laminates. Finally, repeating the same experiments on a similar CFRP system without discrete toughening particles showed that their inclusion significantly increased the impact resistance both with and without prior fatigue damage.
通过联合实验和数值分析,研究了含有和未含有热塑性增韧颗粒的机械疲劳碳纤维增强聚合物(CFRP)复合材料层压板的冲击性能。在层界面添加了增韧颗粒的棱柱形碳纤维/环氧树脂试样在不同载荷振幅下受到机械疲劳,导致表观刚度损失 10%至 15%。疲劳加载后,对试样进行了高分辨率计算机断层扫描(CT),发现试样从自由边缘开始沿长度方向出现了不同程度的分层。此外,无论分层程度如何,所有疲劳试样都能观察到横向基质裂纹。在三种不同速度下的动态三点弯曲配置中,对受损试样的残余弹道冲击性能进行了研究,结果表明,即使是几乎不可见的初始分层也会产生显著的不利影响。此外,还通过死后 CT 扫描和详细的有限元模拟,进一步了解了两种初始损伤对层压板抗冲击性能的影响机制。最后,在不含离散增韧颗粒的类似 CFRP 系统上重复相同的实验,结果表明,无论是否存在先前的疲劳损伤,加入离散增韧颗粒都能显著提高抗冲击性。
Simple double shooting approach with bisection for FRCM reinforced curved masonry prisms subjected to shear
Yu Yuan, Gabriele Milani
doi:10.1016/j.compstruct.2024.118363
FRCM 加固的受剪曲线砌体棱柱体的简单双射法与二分法
In this study, curved masonry pillars reinforced with FRCM subjected to standard shear tests are analyzed through a novel mono-dimensional model, where failure is governed by Mode II. Three approaches with different accuracy are proposed: i) the first, where the outer matrix is neglected; ii) the second, where the inner matrix is assumed rigid; and iii) the third which considers both matrix layers. Matrix and fiber are assumed subjected to a monoaxial state of stress and exchange tangential stresses at the interfaces. The load is applied by incrementing the displacement at the free fiber edge. Material properties of matrix, fiber and interfaces are assumed constant on small portions of the bonded length. Non-linearity is considered penalizing the elastic modulus using the results of the previous time step. The substrate is assumed rigid. The substrate curvature influence is manifested through interface normal stresses, incorporated into the bond-slip constitutive behavior via the Mohr-Coulomb law. The normal stresses can be determined by enforcing radial equilibrium. For the first two models, the field problem is constituted by a system of two 2nd order differential equations into two variables, namely the displacement of the inner (or outer) layer of mortar and of the fiber textile. A 1D shooting is employed, after having converted the boundary value problem (BVP) into an initial value one (IVP), being the latter fully explicit. For the third model, the field problem is constituted by a system of three 2nd order differential equations, and an additional displacement variable is introduced, necessitating a 2D shooting. The validation is carried out through comparisons with existing experimental data. Good predictions of the load-slip curves, for different strengthening configurations (extrados and intrados with two curvature radii), are observed. In addition, an insight into local stress distributions and material degradation for matrix layers and interfaces is obtained.
在本研究中,采用 FRCM 加固的弧形砌体支柱经受标准剪切试验,通过新型单维模型进行分析,其中破坏由模式 II 决定。提出了三种不同精度的方法:i) 第一种,忽略外层基体;ii) 第二种,假定内层基体为刚性;iii) 第三种,同时考虑两层基体。假定基体和纤维处于单轴应力状态,并在界面处交换切向应力。载荷通过增加自由纤维边缘的位移来施加。假定基体、纤维和界面的材料特性在粘合长度的一小部分上保持不变。考虑非线性时,使用前一时间步骤的结果对弹性模量进行惩罚。基体假定为刚性。基体曲率的影响通过界面法向应力表现出来,并通过莫尔-库仑定律纳入粘合滑移构成行为中。法向应力可通过强制径向平衡来确定。对于前两个模型,现场问题由两个二阶微分方程系统构成,其中包含两个变量,即内层(或外层)砂浆和纤维织物的位移。在将边界值问题(BVP)转换为初始值问题(IVP)之后,采用了一维射击,后者是完全显式的。对于第三个模型,现场问题由三个二阶微分方程系统构成,并引入了一个额外的位移变量,因此需要进行二维计算。通过与现有实验数据的比较进行了验证。对于不同的加固结构(具有两个曲率半径的外侧和内侧),荷载-滑移曲线的预测结果良好。此外,还深入了解了基体层和界面的局部应力分布和材料退化情况。
Experimental and numerical investigations on shear behavior of RC beam strengthened with U-wrapped PET FRP
Shi-Jie Mei, Yu-Lei Bai, Jian-Guo Dai
doi:10.1016/j.compstruct.2024.118366
用 U 型缠绕 PET FRP 加固的 RC 梁抗剪行为的实验和数值研究
This paper reports the investigations of experimental and numerical programs on the shear performance of U-shaped Polyethylene Terephthalate (PET) FRP-retrofitted RC beams. Twelve RC beams were fabricated and tested under monotonic three-point loading with the test parameters being FRP strip width and shear span-to-effective depth ratio. A comprehensive analysis and investigation were conducted in terms of the failure modes, shear load–deflection responses, shear capacities, the strain evolution of FRP and stirrups, and the interaction of shear contributions among FRP, stirrups and concrete. Larger debonding strains were observed for PET FRP. Five design guidelines and two models available in the literature were assessed against the measured PET FRP shear contribution. A modified model of the shear contribution for PET FRP was developed and verified by the test results. Finally, a finite element model was established to further understand the shear performance of retrofitted beams, in which the bond-slip relationship between concrete and FRP was considered. The FE model was validated by comparing the test and FE results. The proposed FE model could accurately capture the propagation of shear critical cracks and FRP debonding failure for the specimens with medium and large shear spans.
本文报告了对 U 型聚对苯二甲酸乙二酯(PET)玻璃钢改装 RC 梁剪切性能的实验和数值研究。试验参数为玻璃钢条宽度和剪切跨度与有效深度比。从破坏模式、剪切荷载-挠度响应、剪切承载力、玻璃钢和箍筋的应变演变以及玻璃钢、箍筋和混凝土之间的剪切相互作用等方面进行了全面的分析和研究。在 PET FRP 中观察到了较大的脱粘应变。根据测得的 PET FRP 剪力贡献,对文献中的五项设计准则和两个模型进行了评估。建立了 PET FRP 剪力贡献的修正模型,并通过测试结果进行了验证。最后,建立了一个有限元模型,以进一步了解改装梁的剪切性能,其中考虑了混凝土和 FRP 之间的粘结滑移关系。通过比较试验和有限元结果,对有限元模型进行了验证。所提出的有限元模型能够准确捕捉到中、大剪切跨度试样的剪切临界裂缝扩展和玻璃钢脱粘失效。
Analysis of thermal residual deformation using different FVFs for each ply
Dong-Hwan Yoon, Jun-Ho Byeon, Kyeong-Ho Seo, Yu-Jung Kwon, Jin-Ho Choi
doi:10.1016/j.compstruct.2024.118368
使用不同的 FVF 对各层进行热残余变形分析
The thermal stresses and residual deformations in composite materials are caused by differences in the thermal expansion coefficients between the fiber and matrix, chemical shrinkage of the matrix, and temperature distribution during curing. Complex thermal stresses can cause residual thermal deformations, including spring-in, spring-out, and warpage. Consequently, modifying composite molds is time-consuming and labor-intensive.In this study, composite laminate plates were fabricated using the VARTM and VIP processes. For each ply, thermal deformation analysis using different FVFs was performed, and the results were compared with the experimental results. The analysis error of the thermal residual deformations using various FVF for each ply was 9.9–36.1%, which was lower than that using the uniform FVF for all plies. Additionally, the residual thermal deformations caused by the VIP process were smaller than those caused by the VARTM process.
复合材料中的热应力和残余变形是由纤维和基体之间的热膨胀系数差异、基体的化学收缩以及固化过程中的温度分布造成的。复杂的热应力会导致残余热变形,包括弹入、弹出和翘曲。因此,修改复合材料模具既费时又费力。本研究采用 VARTM 和 VIP 工艺制作了复合材料层压板。使用不同的 FVF 对每层板进行了热变形分析,并将分析结果与实验结果进行了比较。使用不同的 FVF 对各层板进行的热残余变形分析误差为 9.9%-36.1%,低于对所有层板使用统一 FVF 的分析误差。此外,VIP 工艺造成的残余热变形小于 VARTM 工艺造成的残余热变形。
A fast and efficient pseudo-direct identification method for orthotropic elastic properties of multi-layered composite plates
T.A. Bui, P. Lardeur, M. Oudjene, J. Park
doi:10.1016/j.compstruct.2024.118369
多层复合板正交弹性特性的快速高效伪直接识别方法
New types of laminated composites are continuously being developed to meet various requirements involved in engineering applications. Before mass production of these new composite materials can take place, it is necessary to identify their elastic properties. Although current identification methods based on vibration tests and optimization algorithms are highly accurate, their high computation cost is a drawback. To address this issue, this paper proposes a new method to identify orthotropic elastic properties of multi-layered composite plates. The proposed method is based on the Modal Stability Procedure, using the experimental vibration frequencies and corresponding numerical mode shapes of structures. It converges after only two or three iterations without requiring an optimization algorithm. Therefore, the computational cost of the proposed method is significantly lower than that of optimization-based methods. The effectiveness and robustness of this method are demonstrated through three examples with different material, stacking sequences, and geometries including curved plate.
为了满足工程应用中的各种要求,新型层压复合材料不断被开发出来。在大规模生产这些新型复合材料之前,有必要确定其弹性特性。虽然目前基于振动测试和优化算法的识别方法具有很高的准确性,但其计算成本高是一个缺点。针对这一问题,本文提出了一种识别多层复合板正交弹性特性的新方法。该方法基于模态稳定程序,使用结构的实验振动频率和相应的数值模态振型。该方法无需优化算法,只需两三次迭代即可收敛。因此,拟议方法的计算成本大大低于基于优化的方法。通过三个不同材料、堆叠顺序和几何形状(包括曲面板)的示例,证明了该方法的有效性和稳健性。
High cycle fatigue life analysis of unidirectional flax/PLA composites through infrared thermography
Samuel Charca, Liu Jiao-Wang, J.A. Loya, Miguel A. Martínez, Carlos Santiuste
doi:10.1016/j.compstruct.2024.118370
通过红外热成像分析单向亚麻/聚乳酸复合材料的高循环疲劳寿命
The durability of structural components under fatigue loading is a huge concern, especially in laminated composites. During the last few years, flax fibers have also gained an outstanding position as a reinforcement of biopolymeric matrices as polylactic acid (PLA). However, there is limited reported information regarding the fatigue behavior of unidirectional flax/PLA composites. Therefore, fatigue properties of unidirectional flax/PLA composites are evaluated in this work; tools such as infrared thermography and dissipated energy were used in order to establish the fatigue limit, and fracture surface was analyzed. Results show consistent and reliable tensile properties (σut = 234.4 MPa, E = 20.56 GPa, and εf = 0.0181). The fatigue stress-cycle curve was established and fitted to the Basquin and Weibull fatigue models and the fatigue limit (σ∞ ) was obtained as 0.4343 and 0.426 using the thermography and dissipated energy, respectively. Furthermore, the fatigue fracture surface presents a striation on the matrix due to the progressive crack propagation.
疲劳载荷下结构部件的耐久性是一个非常重要的问题,尤其是在层压复合材料中。在过去几年中,亚麻纤维作为聚乳酸(PLA)等生物聚合物基体的增强材料也取得了突出的地位。然而,有关单向亚麻/聚乳酸复合材料疲劳行为的报道却很有限。因此,本研究对单向亚麻/聚乳酸复合材料的疲劳特性进行了评估;为了确定疲劳极限,使用了红外热成像和耗散能量等工具,并对断裂面进行了分析。结果显示了一致而可靠的拉伸性能(σut = 234.4 MPa,E = 20.56 GPa,εf = 0.0181)。建立了疲劳应力-循环曲线,并将其拟合为 Basquin 和 Weibull 疲劳模型,利用热成像和耗散能量分别得出疲劳极限(σ∞ )为 0.4343 和 0.426。此外,由于裂纹的逐渐扩展,疲劳断裂面在基体上呈现出条纹状。
Advanced acoustic design: 3D printed thermoplastic folded core sandwich structures with porous materials and microperforations for enhanced sound absorption
Shanigaram Mallesh, Junhyeok Hwang, Huncheol Choi, Dong-Jun Hong, Changmin Seok, Byeongsu Kwak, Soo-Yong Lee, Youngwoo Nam
doi:10.1016/j.compstruct.2024.118371
先进的声学设计:采用多孔材料和微穿孔的 3D 打印热塑性折叠芯材夹层结构,可增强吸音效果
This study introduces a novel sound-absorbing sandwich structure with a folded core, created through 3D printing technology, to address the challenge of weak sound absorption in the low-frequency range in sound absorption materials (SAMs). The structure comprises chopped carbon fiber–dispersed thermoplastic polyamide (CF-PA), continuous carbon fiber (CCF) filaments, and polyurethane (PU) foam coated with graphene oxide (GO). Simulation studies revealed that optimized structural parameters and microperforation diameters resulted in enhanced sound absorption coefficient (SAC) of 99 % or more at 1250 Hz, within the low-frequency range (160–1600 Hz). The GO-coated PU foam SAMs demonstrated excellent sound absorption performance measured in the high-frequency range (1600–6000 Hz), achieving 99 % SAC at 2400 Hz. Furthermore, the fabricated folded core structure exhibited outstanding sound absorption performance, achieving SAC of 99 % at 732 Hz measured in the low-frequency (160–1600 Hz) band and 99 % at 600 Hz, showcasing broad absorption capabilities measured in the high-frequency band (160–6000 Hz). Additionally, a flatwise compression test on the structure filled with GO-coated PU foam demonstrated a 32 % improvement in compressive load, indicating the structure’s versatility for various applications.
本研究介绍了一种通过三维打印技术制作的带有折叠核心的新型吸音夹层结构,以解决吸音材料(SAM)在低频范围内吸音能力较弱的难题。该结构由切碎的碳纤维分散热塑性聚酰胺(CF-PA)、连续碳纤维(CCF)丝和涂有氧化石墨烯(GO)的聚氨酯(PU)泡沫组成。模拟研究表明,优化结构参数和微穿孔直径后,在 1250 Hz 的低频范围(160-1600 Hz)内,吸音系数(SAC)提高了 99% 或更多。在高频范围(1600-6000 Hz)内测量,GO 涂层聚氨酯泡沫 SAM 具有出色的吸音性能,在 2400 Hz 时吸音系数达到 99%。此外,所制造的折叠芯结构也表现出了出色的吸音性能,在低频(160-1600 Hz)频段的 732 Hz 处达到了 99 % 的 SAC 值,在 600 Hz 处达到了 99 % 的 SAC 值,展示了在高频频段(160-6000 Hz)的广泛吸音能力。此外,对填充有 GO 涂层聚氨酯泡沫的结构进行的平向压缩测试表明,压缩载荷提高了 32%,这表明该结构可用于多种应用。
Novel kraft-lignin-based adhesives for the production of particleboards
Miroslav Němec, Luboš Prokůpek, Vojtěch Obst, Tomáš Pipíška, Pavel Král, Štěpán Hýsek
doi:10.1016/j.compstruct.2024.118344
用于生产刨花板的新型牛皮纸-木质素基粘合剂
Lignin is produced worldwide in pulp mills and is currently mainly used for energy recovery. Because of its chemical properties, one possible utilisation is the production of lignin-based materials. Currently, developed lignin-based adhesives are based mainly on lignosulfonate instead of kraft lignin since lignosulfonate is more reactive than kraft lignin. However, worldwide substantially more kraft lignin is produced. The presented research deals with the development of resin chemically modified with kraft lignin up to 40% (w/w) content of kraft lignin. The synthesis of adhesives is described, and developed adhesives are characterised. Namely, viscosity, mechanical properties of resins and results of differential scanning calorimetry are presented. Furthermore, the developed kraft-lignin-based adhesives were used for the production of particleboards. Pre-pressing in a cold press followed by hot pressing in a laboratory press was used for the production of particleboards. The physical (thickness swelling, moisture uptake, vertical density profile), as well as mechanical (internal bonding, modulus of rupture, modulus of elasticity in three-point bending) properties of particleboards, were evaluated. The results clearly show that kraft lignin can be used for the production of lignin-based adhesives for the production of particleboards
木质素产自世界各地的纸浆厂,目前主要用于能源回收。由于其化学特性,一种可能的利用方式是生产木质素基材料。目前,开发的木质素基粘合剂主要基于木质素磺酸盐而非牛皮纸木质素,因为木质素磺酸盐比牛皮纸木质素更具活性。然而,全世界生产的牛皮纸木质素要多得多。本文介绍的研究涉及用牛皮纸木质素化学改性树脂的开发,牛皮纸木质素含量最高可达 40%(重量比)。对粘合剂的合成进行了描述,并对开发的粘合剂进行了表征。例如,介绍了粘度、树脂的机械性能和差示扫描量热法的结果。此外,开发的牛皮纸-木质素基粘合剂被用于生产刨花板。在生产刨花板时,先在冷压机中进行预压,然后在实验室压机中进行热压。对刨花板的物理(厚度膨胀、吸湿性、垂直密度曲线)和机械(内部粘合、断裂模数、三点弯曲弹性模量)性能进行了评估。结果清楚地表明,牛皮纸木质素可用于生产刨花板的木质素基粘合剂
Enhancing mode-II delamination resistance of hybrid woven composite materials of glass/Kevlar fabrics by stitching with Kevlar threads
Masoud Mohammadi, Eduardo M. Sosa
doi:10.1016/j.compstruct.2024.118365
用凯芙拉纤维线缝合玻璃/凯芙拉纤维混合编织复合材料,增强其抗模式 II 分层能力
This study analyzes the effects of stitching a hybrid composite beam on its Mode-II delamination to enhance the bonding between a Kevlar-Kevlar interface. The material under investigation is a composite material manufactured from fiberglass and Kevlar fabrics stitched together with Kevlar threads before the infusion of epoxy resin. End-notched flexure tests and multiscale finite element simulations are conducted to validate a glass/epoxy composite with a glass-glass interface. Calibrated simulations are then used to perform a parametric study on stitching parameters, including stitch spacing, pitch, and direction on a composite with a Kevlar-Kevlar interface. The parametric study on Kevlar-Kevlar specimens revealed an average improvement of 17 % in maximum load capacity and 103 % in tangent stiffness in stitched specimens compared to unstitched specimens. Additionally increasing stitch density up to 0.02 mm−2 significantly enhances mechanical performance, while higher densities do not provide significant additional improvements.
本研究分析了缝合混合复合材料梁对其模态 II 分层的影响,以增强凯夫拉纤维-凯夫拉纤维界面之间的粘合力。所研究的材料是一种复合材料,由玻璃纤维和 Kevlar 纤维制成,在注入环氧树脂之前用 Kevlar 线缝合在一起。通过端面缺口挠曲试验和多尺度有限元模拟,对具有玻璃-玻璃界面的玻璃/环氧复合材料进行了验证。然后利用校准模拟对缝合参数进行参数化研究,包括凯芙拉-凯芙拉界面复合材料的缝合间距、间距和方向。对 Kevlar-Kevlar 试样的参数研究表明,与未缝合试样相比,缝合试样的最大承载能力平均提高了 17%,切线刚度平均提高了 103%。此外,缝合密度增加到 0.02 mm-2 时,机械性能显著提高,而更高的密度则没有明显的额外改善。
Characterization of pressure-dependent nonlinear bending behavior of yarns and its application in modeling the compression of 2D woven fabrics
Yiding Li, Weijie Zhang, Shibo Yan
doi:10.1016/j.compositesa.2024.108346
纱线随压力变化的非线性弯曲特性及其在二维机织物压缩建模中的应用
This paper investigates the pressure-dependent nonlinear bending behavior of yarns, which is essential for the application of the virtual fiber modeling (VFM) method in the mechanical analyses of fabrics. An experimental method, along with a theoretical model based on classical beam theory, is presented to characterize the varying bending stiffness of yarns under different pressures. A tailored beam user element is then developed, incorporating the nonlinear bending behavior and combined with a truss element to create a physics-based virtual fiber formulation. Utilizing this formulation, the original kinematic VFM method is extended for modeling the mechanical response of 2D woven fabrics under compression. The predicted results of the proposed model closely match the reported experiment, demonstrating the significance of introducing the nonlinear bending behavior of yarns. This method can be a valuable tool for the fabric compression process and generating realistic mesoscale geometries for textile composites
本文研究了纱线随压力变化的非线性弯曲行为,这对于在织物机械分析中应用虚拟纤维建模(VFM)方法至关重要。本文介绍了一种实验方法以及基于经典梁理论的理论模型,用于描述纱线在不同压力下的弯曲刚度变化。然后,结合非线性弯曲行为开发了一种定制的梁用户元素,并与桁架元素相结合,创建了基于物理的虚拟纤维配方。利用这一公式,原有的运动虚拟纤维模型方法被扩展用于二维编织物在压缩下的机械响应建模。所建模型的预测结果与报告的实验结果非常吻合,证明了引入纱线非线性弯曲行为的重要性。该方法是织物压缩过程和生成纺织复合材料真实中尺度几何形状的重要工具。
Research progress and prospects of laser cleaning for CFRP: A review
Junyi Gu, Xuan Su, Yang Jin, Donghe Zhang, Wenqin Li, Jie Xu, Bin Guo
doi:10.1016/j.compositesa.2024.108349
CFRP 激光清洗的研究进展与前景:综述
CFRP is being widely used as a lightweight composite material in the aerospace field. At the same time, CFRP surface cleaning has gained attention. Laser cleaning technology, as an emerging surface cleaning method, has shown broad application prospects in cleaning CFRP surface resin, release agent, paint, etc. This paper firstly briefly reviews the traditional CFRP cleaning methods, and then focuses on the research progress of laser cleaning principles and the influencing parameters. Afterwards, the effect of laser cleaning on substrate performance is discussed. In particular, the damage characteristics and mechanisms of laser cleaning on composite substrates have received sufficient attention. Finally, the research challenges and trends in laser cleaning on composite materials are discussed. In conclusion, the review provides a reference to the research of laser cleaning on composites and promotes the promotion of laser cleaning technology in the aerospace field.
CFRP 作为一种轻质复合材料被广泛应用于航空航天领域。与此同时,CFRP 的表面清洁问题也备受关注。激光清洗技术作为一种新兴的表面清洗方法,在 CFRP 表面树脂、脱模剂、涂料等的清洗方面有着广阔的应用前景。本文首先简要回顾了传统的 CFRP 清洗方法,然后重点介绍了激光清洗原理及影响参数的研究进展。随后,讨论了激光清洗对基材性能的影响。其中,激光清洗对复合材料基材的损伤特征和机理得到了足够的重视。最后,讨论了激光清洗复合材料的研究挑战和趋势。总之,本综述为激光清洗复合材料的研究提供了参考,促进了激光清洗技术在航空航天领域的推广。
High-performance PEEK composite materials research on 3D printing for neutron and photon radiation shielding
Yi Cao, Hao Yang, Kun Wan, Dichen Li, Qingming He, Hongchun Wu
doi:10.1016/j.compositesa.2024.108352
用于中子和光子辐射屏蔽的高性能 PEEK 复合材料 3D 打印研究
With the rapid advancement of nuclear energy technology, addressing technical challenges in the field of radiation shielding, particularly achieving lightweight and efficient shielding against neutron and multiple radiation types, remains a formidable task. To address the aforementioned issues, this study investigates the 3D printing performance of polyether ether ketone (PEEK) composite materials for shielding against both neutron and photon multibeam radiation. High-content 3D printing filament is developed, with simultaneous shielding capabilities against neutron and photon radiation. This research successfully accomplishes the high-density 3D printing of PEEK shielding composites with increased concentrations of boron carbide(B4C), tungsten(W), and both materials. The experimental results indicate that 3D printed specimens of B4C/W/PEEK, a neutron and photon shielding composite material, exhibit excellent mechanical properties. Importantly, the radiation shielding composite 3D function parts achieves effective shielding against muitibeam radiation and weight reduction compared to traditional radiation shielding materials.
随着核能技术的飞速发展,解决辐射屏蔽领域的技术难题,特别是实现轻质高效的中子和多种辐射屏蔽,仍然是一项艰巨的任务。为解决上述问题,本研究探讨了聚醚醚酮(PEEK)复合材料的三维打印性能,用于屏蔽中子和光子多波束辐射。开发出的高含量三维打印丝具有同时屏蔽中子和光子辐射的能力。这项研究成功地完成了碳化硼(B4C)、钨(W)以及两种材料浓度增加的 PEEK 屏蔽复合材料的高密度三维打印。实验结果表明,3D 打印的 B4C/W/PEEK 中子和光子屏蔽复合材料试样具有优异的机械性能。重要的是,与传统的辐射屏蔽材料相比,辐射屏蔽复合材料三维功能部件实现了对米氏辐射的有效屏蔽并减轻了重量。
Towards understanding the machining process in grinding of ceramic matrix composites: a review
Yichuan Ran, Jiansong Sun, Renke Kang, Zhigang Dong, Yan Bao
doi:10.1016/j.compositesb.2024.111657
了解陶瓷基复合材料磨削加工过程:综述
The challenge of machining ceramic matrix composites (CMCs) arises from their hard and brittle, anisotropic, and heterogeneous nature, making them prone to damage such as edge chipping, fiber fracture, and interfacial debonding during grinding. To gain a thorough understanding of CMCs' grinding performance, this paper discusses in detail the removal behavior under the action of abrasive grain, focusing on the micro-interaction of abrasive grain and material. Following this analysis, various strategies for modeling grinding forces are elaborated. Then, we outline the quality evaluation of CMCs and offer solutions to mitigate grinding damage by comprehensively assessing the factors affecting material removal in CMCs. Ultimately, the prospects and potential advancements in the application of grinding processes for CMCs are highlighted.
陶瓷基复合材料(CMC)具有硬而脆、各向异性和异质性等特点,因此在加工过程中容易出现边缘崩裂、纤维断裂和界面脱粘等损伤,这给陶瓷基复合材料的加工带来了挑战。为深入了解 CMC 的磨削性能,本文详细讨论了其在磨粒作用下的去除行为,重点关注磨粒与材料的微观相互作用。分析之后,阐述了各种磨削力建模策略。然后,我们概述了 CMC 的质量评估,并通过全面评估影响 CMC 中材料去除的因素,提出了减轻研磨损伤的解决方案。最后,我们强调了 CMC 研磨工艺的应用前景和潜在进步。
Mechanisms of void nucleation on neat and Glass Syntactic PolyPropylene using in situ synchrotron radiation tomography
Theophile Hourdou, Cristian Ovalle, Sebastien Blassiau, Alain Thionnet, Lucien Laiarinandrasana
doi:10.1016/j.compositesb.2024.111696
利用原位同步辐射断层扫描分析纯聚丙烯和玻璃纤维合成聚丙烯上的空洞成核机制
The mechanisms of void nucleation of a hollow glass syntactic foam during tensile loading were studied in depth. Flat-notched geometries, cut-out from neat and Glass Syntactic Polypropylene (GSPP), were investigated by in situ microtomography. Notched specimens with two notch root radii, 4 mm and 0.15 mm named respectively N 4 and N 0 . 15 , to set initial triaxial stress state in the minimum cross section, were observed. Tomographic data sets, with a resolution of 1 . 3 μ m , from stepwise tensile loading, at the SOLEIL synchrotron radiation facilities, were retrieved from the notched zone. In addition, they allowed gathering both the width and thickness evolution in the minimum cross section, and the notch opening displacement during the tests. In line with literature, neat PolyPropylene (PP) showed crazes concentration at the specimen core in N 4 specimen, whereas, in N 0 . 15 specimen, they were located at the notch root. In isolated Hollow Glass Microspheres (HGM), mechanisms of crazing and debonding were correspondingly highlighted in the PP matrix and at the poles of HGM. Finally, in GSPP, decohesion follows the same trend as in neat PP, i.e. at the specimen core and near the notch, respectively in N 4 and in N 0 . 15 geometry. Scenarios of void nucleation and propagation were outlined. The initiation of the brittle crack in the GSPP is mainly due to the matrix-HGM decohesion followed by the coalescence of near neighbouring caps.
深入研究了中空玻璃合成泡沫在拉伸加载过程中的空洞成核机制。通过原位显微层析成像技术研究了从纯玻璃和玻璃合成聚丙烯(GSPP)中切割出来的平缺口几何形状。缺口试样有两个缺口,缺口根部半径分别为 4 毫米和 0.15 毫米,分别命名为 N 4 和 N 0 .15 的缺口试样,以在最小横截面上设定初始三轴应力状态。断层扫描数据集的分辨率为 1 .3 μ m 的断层扫描数据集,这些数据集是在 SOLEIL 同步辐射设施上从缺口区逐步拉伸加载获得的。此外,在测试过程中,还可以收集最小截面的宽度和厚度变化以及缺口开口位移。与文献一致,在 N 4 试样中,纯聚丙烯(PP)的裂纹集中在试样核心,而在 N 0 .15 试样中,裂纹集中在缺口根部。在孤立的中空玻璃微球(HGM)中,开裂和脱粘的机理相应地突出表现在 PP 基体和 HGM 的两极。最后,在 GSPP 中,脱粘的趋势与纯 PP 相同,即在 N 4 和 N 0 .15 几何形状。概述了空洞成核和扩展的情况。GSPP 中脆性裂纹的产生主要是由于基体-HGM 的脱粘,然后是近邻盖帽的凝聚。