International Journal of Impact Engineering最新文献

Research on the evolution of state field and damage range of multiple source cloud explosions 多源云爆炸状态场和破坏范围演变研究

IF 5.1 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Impact Engineering

Pub Date : 2024-11-13 DOI: 10.1016/j.ijimpeng.2024.105182

Jiafan Ren, Chunhua Bai, Xingyu Zhao, Linghui Zeng, Zhongqi Wang

Multi-source cloud detonations, as a form of industrial hazard, pose a significantly increased risk. To investigate the distribution of the state field and the extent of damage caused by multi-source cloud detonations, an experimental setup in an open space, along with numerical simulation, was employed to reconstruct the state field. The equivalent area method was utilized to analyze the distribution patterns of the overpressure field, impulse field, and the combined overpressure-impulse field associated with multi-source cloud detonations. The study demonstrates that the numerical simulation method developed aligns with experimental outcomes within a 10 % margin of error, thereby validating the accuracy of the simulation model. As the distance between the multiple explosive sources in a cloud detonation increases, the overpressure field, impulse field, and the combined overpressure-impulse field all exhibit a trend of initially increasing and then decreasing. Notably, the threshold ranges of 0.1 MPa, 0.05 MPa, and 0.03 MPa for multi-point cloud detonations each reach their maximum when the distribution distance of the explosive sources is twice the radius of the threshold range for a single explosive source. The overpressure-impulse criterion is found to be a more rational metric for characterizing the damage extent of multi-point cloud detonations. According to this criterion, the extent of level-five damage under various conditions is approximately located at a position 5.5 times the scale distance.

多源云爆作为一种工业危害形式，其风险大大增加。为了研究状态场的分布以及多源云爆弹造成的破坏程度，我们在开放空间中利用实验装置和数值模拟来重建状态场。利用等效面积法分析了与多源云爆相关的超压场、脉冲场以及超压-脉冲组合场的分布模式。研究表明，所开发的数值模拟方法与实验结果的吻合度在 10% 的误差范围内，从而验证了模拟模型的准确性。随着云爆炸中多个爆炸源之间距离的增加，超压场、脉冲场以及超压-脉冲综合场都呈现出先增大后减小的趋势。值得注意的是，当爆炸源分布距离是单个爆炸源阈值范围半径的两倍时，多点云爆的阈值范围 0.1 兆帕、0.05 兆帕和 0.03 兆帕均达到最大值。研究发现，超压-脉冲标准是表征多点云爆破破坏程度的更合理的指标。根据该标准，各种条件下的五级破坏范围大致位于规模距离的 5.5 倍位置。

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引用次数: 0

Effect of pre-shock on the expanding fracture behavior of 1045 steel cylindrical shell under internal explosive loading 预冲击对内部爆炸加载下 1045 钢圆柱形外壳膨胀断裂行为的影响

IF 5.1 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Impact Engineering

Pub Date : 2024-11-12 DOI: 10.1016/j.ijimpeng.2024.105183

Huaizhi Zhao, Zhaoliang Guo, Shiwen Zhang, Jiakun Dan, Mingtao Liu, Tiegang Tang

Explosively driven expansion fractures in metallic shells will be preceded by a compression shock wave, which inevitably changes the mechanical and microstructural state of the shell materials and thus affects their subsequent dynamic deformation and expansion fracture processes. To understand the influence of pre-shock pressure on the dynamic expansion fracture behavior of metallic shells, the incident shock waves with varying peak pressure were generated in a 1045 steel cylindrical shell by sweeping detonation wave loading. The pre-shock and subsequent expansion fracture processes were continuously diagnosed by combining a high-speed framing camera and the arrayed Photon Doppler Velocimetry (PDV) measurements to obtain the fracture strains at different axial positions (corresponding to different pre-shock pressures). The results clearly show that the pre-shock pressure during detonation loading has a significant effect on the expansion fracture properties of the 1045 steel cylinder; the fracture strain remarkably decreases with the increase of pre-shock pressure from ∼19 GPa to ∼20 GPa and then changes gently in the range of ∼20 GPa to ∼22 GPa. Metallurgical analyses reveal increased densities of microstructural defects, including dislocations and deformation twins, when a shock wave passes through, resulting in a reduced capacity for further defect storage in the shocked metals, ultimately leading to a decrease in the fracture strain during the subsequent expansion deformation process.

金属壳体在爆炸驱动膨胀断裂之前会产生压缩冲击波，这不可避免地会改变壳体材料的力学和微观结构状态，从而影响其后续的动态变形和膨胀断裂过程。为了了解冲击前压力对金属壳体动态膨胀断裂行为的影响，我们通过扫频爆轰波加载在 1045 钢圆柱形壳体中产生了不同峰值压力的入射冲击波。通过高速取景相机和阵列式光子多普勒速度测量仪（PDV）测量，获得不同轴向位置（对应不同冲击前压力）的断裂应变，从而对冲击前和随后的膨胀断裂过程进行连续诊断。结果清楚地表明，爆轰加载时的预震压力对 1045 钢圆柱体的膨胀断裂性能有显著影响；断裂应变随着预震压力从 ∼19 GPa 到 ∼20 GPa 的增加而显著减小，然后在 ∼20 GPa 到 ∼22 GPa 范围内平缓变化。冶金分析表明，当冲击波通过时，微结构缺陷（包括位错和变形孪晶）的密度增加，导致冲击金属中进一步储存缺陷的能力降低，最终导致在随后的膨胀变形过程中断裂应变降低。

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引用次数: 0

Low-velocity penetration behavior of ice by steel projectile 钢制弹丸对冰的低速穿透行为

IF 5.1 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Impact Engineering

Pub Date : 2024-11-09 DOI: 10.1016/j.ijimpeng.2024.105163

Junzheng Yue , Zhoupeng Gu , Chenguang Huang , Xianqian Wu

In this study, the penetration of a steel projectile into a semi-infinite ice target is investigated through experiment and numerical simulation. Five tests with initial impact velocity varying from 42.5 to 110 m/s are conducted. The penetrating behavior of the projectile and the dynamic response of the ice target are captured by a high-speed camera. The experimental results show that the impact velocity has great impact on the dynamic behavior and failure mode of the ice target. Under a low-speed impact, the ice target forms a crater at the impact surface. However, a penetration tunnel is formed under a high-speed impact. The crater diameter and penetration depth increase almost linearly with increasing the impact velocity. Furthermore, the numerical simulation for the tests is carried out using the continuum discontinuum element method (CDEM). The simulated penetration depth history of the projectile and the failure characteristics of the ice target agree with the experimental results, validating the numerical simulation model. It indicates that the ice crater angle keeps almost the same during a penetration. In addition, the maximum deceleration of the projectile and the maximum von Mises stress of the ice elements increase with increasing the impact velocity. These results provide the failure behavior and numerical simulation method for ice penetration, improving the understanding of dynamic fracturing mechanism of ice in engineering applications.

本研究通过实验和数值模拟研究了钢制弹丸穿透半无限冰靶的情况。共进行了五次试验，冲击初速度从 42.5 米/秒到 110 米/秒不等。高速摄像机捕捉了弹丸的穿透行为和冰靶的动态响应。实验结果表明，冲击速度对冰靶的动态行为和破坏模式有很大影响。在低速撞击下，冰靶在撞击表面形成一个凹坑。然而，在高速冲击下会形成一个穿透隧道。随着撞击速度的增加，凹坑直径和穿透深度几乎呈线性增加。此外，试验的数值模拟是采用连续非连续单元法（CDEM）进行的。模拟的弹丸穿透深度历史和冰靶的破坏特征与实验结果一致，验证了数值模拟模型。结果表明，在穿透过程中，冰坑角度几乎保持不变。此外，弹丸的最大减速度和冰元件的最大 von Mises 应力随着撞击速度的增加而增大。这些结果提供了冰穿透的破坏行为和数值模拟方法，提高了工程应用中对冰的动态断裂机理的认识。

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引用次数: 0

A comment on “Plasticity, ductile fracture and ballistic impact behavior of Ti-6Al-4V Alloy” by Wu et al. (2023), Int. J. Impact Eng. 174:104493 对 Wu 等人 (2023) 的 "Ti-6Al-4V 合金的塑性、韧性断裂和弹道冲击行为 "的评论，Int.J. Impact Eng.174:104493

IF 5.1 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Impact Engineering

Pub Date : 2024-11-09 DOI: 10.1016/j.ijimpeng.2024.105165

Z. Rosenberg, Y. Vayig

We discuss a common misunderstanding made by many authors, regarding their data analysis for blunt rigid projectiles perforating thin metallic plates. The problem with their analysis is that they use the empirical relation of Lambert and Jonas (1976), which was suggested for eroding projectiles penetrating thick plates. Instead, they should use the physics-based model of Recht and Ipson (1963) to account for their data. The paper of Wu et al. (2023) is one of these works, and we use their ballistics results to demonstrate the benefits of the R-I model to account for their data.

我们讨论了许多作者在对穿透金属薄板的钝硬弹丸进行数据分析时普遍存在的误解。他们分析的问题在于，他们使用了 Lambert 和 Jonas（1976 年）的经验关系，该关系是针对侵蚀射弹穿透厚板而提出的。相反，他们应该使用 Recht 和 Ipson（1963 年）基于物理学的模型来解释他们的数据。Wu 等人（2023 年）的论文就是这些著作中的一篇，我们利用他们的弹道学结果来证明 R-I 模型在解释他们的数据方面的优势。

引用次数: 0

Tensile properties and constitutive modeling of Kevlar29 fibers: From filaments to bundles Kevlar29 纤维的拉伸性能和构成模型：从细丝到纤维束

IF 5.1 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Impact Engineering

Pub Date : 2024-11-09 DOI: 10.1016/j.ijimpeng.2024.105164

Xuan Zhou, Wenke Ren, Kaiying Wang, Rui Zhu, Lizhi Xu, Guangfa Gao

This paper experimentally investigates the tensile properties of Kevlar29 filaments and fiber bundles, revealing the size and strain rate effects on the mechanical properties of fiber bundles. The fracture modes and mechanisms of the fibers were analyzed, and viscoelastic constitutive models at the fiber bundle scale and constitutive models for filaments-bundles based on the Weibull distribution were established. The results show that Kevlar29 fiber bundles exhibit significant strain rate effects: as the strain rate increases, tensile strength and modulus increase, while fracture strain and toughness decrease. Under quasi-static loading, the fracture modes of the fibers are mainly fibrillation or shear flow, but as the strain rate increases, the failure modes shift towards brittle fracture. Both constitutive models can accurately predict the tensile properties of fiber bundles at different strain rates. The accuracy and applicability of the filament-to-bundle constitutive model were verified through numerical simulations, demonstrating that the model better describes the size effect of fibers and quantifies the damage to the fiber bundles.

本文通过实验研究了 Kevlar29 长丝和纤维束的拉伸性能，揭示了尺寸和应变速率对纤维束力学性能的影响。分析了纤维的断裂模式和机理，并建立了纤维束尺度的粘弹性构成模型和基于威布尔分布的丝束构成模型。结果表明，Kevlar29 纤维束表现出显著的应变率效应：随着应变率的增加，拉伸强度和模量增加，而断裂应变和韧性降低。在准静态加载下，纤维的断裂模式主要是纤维化或剪切流，但随着应变速率的增加，断裂模式转向脆性断裂。这两种构成模型都能准确预测纤维束在不同应变速率下的拉伸特性。通过数值模拟验证了丝束构成模型的准确性和适用性，表明该模型能更好地描述纤维的尺寸效应并量化纤维束的损伤。

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引用次数: 0

An experimental setup to study the collision force between brittle impacting bodies 研究脆性撞击体之间碰撞力的实验装置

IF 5.1 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Impact Engineering

Pub Date : 2024-11-08 DOI: 10.1016/j.ijimpeng.2024.105160

Valerio De Biagi , Maddalena Marchelli

A new experimental setup to study the interaction between two brittle bodies which can experience crushing, comminution or fragmentation during impact is herein presented. The system consists of a free falling body and an instrumented impacted plate, onto which an accelerometer is installed, lying on three force ring cells. The recorded acceleration is decomposed into Intrinsic Mode Functions thanks to a Variational Mode Decomposition technique to obtain relevant time-histories associated with specific vibration frequencies. The mass participating to each mode is obtained by comparing the discrete Fourier transforms of force and acceleration. Finally, the adoption of a high-speed camera provides additional insights into the interaction, in particular when non-spherical bodies are considered. The results of a small experimental campaign serving as a benchmark are presented and discussed.

本文介绍了一种新的实验装置，用于研究两个脆性体之间的相互作用，这两个脆性体在撞击过程中会发生挤压、粉碎或碎裂。该系统由一个自由落体和一个带仪器的撞击板组成，撞击板上安装了一个加速度计，该加速度计位于三个力环单元上。利用变异模态分解技术将记录的加速度分解为本征模态函数，从而获得与特定振动频率相关的时间历史。通过比较力和加速度的离散傅里叶变换，可获得参与每个模式的质量。最后，通过采用高速摄像机，特别是在考虑非球形物体时，对相互作用有了更深入的了解。本文介绍并讨论了作为基准的小型实验活动的结果。

引用次数: 0

Simulating the break-up, debris formation and throw of concrete structures under explosive loading 模拟爆炸荷载下混凝土结构的破裂、碎片形成和抛掷

IF 5.1 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Impact Engineering

Pub Date : 2024-11-08 DOI: 10.1016/j.ijimpeng.2024.105154

Christoph Grunwald , Malte von Ramin , Werner Riedel , Alexander Stolz , Stefan Hiermaier

Malicious acts, but likewise unintended accidental explosions, can lead to severe structural damage and resulting debris throw, which poses a significant threat to humans and facilities. Until now, risk analysis is based mainly on empirical data, since the reliable simulation of structural break-up, dissolution and emergence of secondary fragments for real structures is still challenging. In this paper, we investigate the application of a mesoscale description of concrete with finite elements to predict the dispersal of fragments out of dynamically loaded concrete specimens. We demonstrate that the approach delivers accurate predictions for maximum velocity and total debris mass. Further, it is even able to resolve the debris mass distribution with very reasonable quality, a result rarely found in literature up to today. The detailed resolution of the debris field allows furthermore a more thorough determination of the aerodynamic factors governing the subsequent flight phase. We compare the results using different assumptions in terms of flight distances and safety maps.

无论是恶意行为，还是意外爆炸，都可能导致严重的结构损坏和碎片飞散，对人类和设施构成重大威胁。迄今为止，风险分析主要基于经验数据，因为对真实结构的结构破裂、溶解和二次碎片的出现进行可靠模拟仍是一项挑战。在本文中，我们研究了如何应用有限元对混凝土进行中尺度描述，以预测碎片从动态加载的混凝土试件中扩散出来的情况。我们证明，该方法能准确预测最大速度和碎片总质量。此外，它甚至能够以非常合理的质量解析碎片质量分布，这是迄今为止在文献中很少发现的结果。通过对碎片场的详细解析，还可以更全面地确定影响后续飞行阶段的空气动力因素。我们比较了在飞行距离和安全地图方面使用不同假设得出的结果。

{"title":"Simulating the break-up, debris formation and throw of concrete structures under explosive loading","authors":"Christoph Grunwald , Malte von Ramin , Werner Riedel , Alexander Stolz , Stefan Hiermaier","doi":"10.1016/j.ijimpeng.2024.105154","DOIUrl":"10.1016/j.ijimpeng.2024.105154","url":null,"abstract":"<div><div>Malicious acts, but likewise unintended accidental explosions, can lead to severe structural damage and resulting debris throw, which poses a significant threat to humans and facilities. Until now, risk analysis is based mainly on empirical data, since the reliable simulation of structural break-up, dissolution and emergence of secondary fragments for real structures is still challenging. In this paper, we investigate the application of a mesoscale description of concrete with finite elements to predict the dispersal of fragments out of dynamically loaded concrete specimens. We demonstrate that the approach delivers accurate predictions for maximum velocity and total debris mass. Further, it is even able to resolve the debris mass distribution with very reasonable quality, a result rarely found in literature up to today. The detailed resolution of the debris field allows furthermore a more thorough determination of the aerodynamic factors governing the subsequent flight phase. We compare the results using different assumptions in terms of flight distances and safety maps.</div></div>","PeriodicalId":50318,"journal":{"name":"International Journal of Impact Engineering","volume":"196 ","pages":"Article 105154"},"PeriodicalIF":5.1,"publicationDate":"2024-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142662746","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Dynamic tensile behaviors and crack propagation in fiber-reinforced cementitious composites: Experimental investigation and peridynamic simulation 纤维增强水泥基复合材料的动态拉伸行为和裂纹扩展：实验研究与周动态模拟

IF 5.1 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Impact Engineering

Pub Date : 2024-11-06 DOI: 10.1016/j.ijimpeng.2024.105161

Man Wang , Liang Li , Jianjun Ma , Jun Wu , Xiuli Du

Fiber-Reinforced Cementitious Composites (FRCC) have gained significant attention in engineering applications due to their superior mechanical properties and toughness, particularly under high strain rate conditions. This study performed dynamic tensile tests on FRCC at high strain rates (35–110 s⁻¹) using a Split Hopkinson Tensile Bar (SHTB) apparatus. Additionally, a novel Peridynamic (PD) model was developed for the SHTB and FRCC system, leveraging the advanced capabilities of the emerging PD theory. The study compared and analyzed dynamic tensile strength, ultimate tensile strain, strain rate effects, failure modes, and crack development in FRCC with different fiber ratios at various high strain rates, using both experimental data and PD simulations. The results show that the PD-SHTB-FRCC dynamic model developed in this study exhibits high consistency between numerical simulations and experimental findings, effectively capturing the processes of crack initiation, propagation, and complete failure in FRCC specimens. The dynamic tensile properties of FRCC improve significantly with increased strain rates, with polyethylene (PE) fibers providing superior reinforcement compared to steel fibers. Notably, the dynamic tensile strength, peak tensile stress, and ultimate tensile strain of FRCC increase significantly with rising strain rates, with specimens containing higher PE fiber content showing a more pronounced enhancement effect. For strain rates between 42.6 s⁻¹ and 76.1 s⁻¹, considering dynamic tensile strength, ultimate tensile strain, and peak tensile stress, the optimal combination for resisting dynamic tensile loads was 1.5 % PE fibers and 0.5 % steel fibers. At a strain rate of 99.8 s⁻¹, a 2 % PE fiber ratio alone provided the best performance.

纤维增强水泥基复合材料（FRCC）因其卓越的机械性能和韧性，尤其是在高应变率条件下的机械性能和韧性，在工程应用中获得了极大的关注。本研究使用分体式霍普金森拉伸棒（SHTB）设备对 FRCC 进行了高应变率（35-110 s-¹）动态拉伸试验。此外，还为 SHTB 和 FRCC 系统开发了一个新颖的周动力 (PD) 模型，充分利用了新兴 PD 理论的先进功能。研究利用实验数据和 PD 模拟，比较和分析了不同纤维比的 FRCC 在各种高应变速率下的动态拉伸强度、极限拉伸应变、应变速率效应、破坏模式和裂纹发展。结果表明，本研究开发的 PD-SHTB-FRCC 动态模型在数值模拟和实验结果之间表现出高度的一致性，能有效捕捉 FRCC 试样中裂纹的产生、扩展和完全破坏的过程。随着应变速率的增加，FRCC 的动态拉伸性能显著提高，与钢纤维相比，聚乙烯（PE）纤维具有更优越的加固性能。值得注意的是，FRCC 的动态拉伸强度、峰值拉伸应力和极限拉伸应变随着应变速率的增加而显著增加，其中聚乙烯纤维含量较高的试样显示出更明显的增强效果。应变速率在 42.6 s-¹ 和 76.1 s-¹ 之间时，考虑到动态拉伸强度、极限拉伸应变和峰值拉伸应力，抵抗动态拉伸载荷的最佳组合是 1.5 % 聚乙烯纤维和 0.5 % 钢纤维。在应变速率为 99.8 s-¹ 时，仅 2 % 的聚乙烯纤维比例就能提供最佳性能。

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引用次数: 0

Investigations of high-speed projectile impact on symmetric sandwich structures containing solid propellant with core perforations 研究高速射弹对装有固体推进剂的对称夹层结构的冲击，夹层结构的核心有穿孔

IF 5.1 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Impact Engineering

Pub Date : 2024-11-05 DOI: 10.1016/j.ijimpeng.2024.105153

Junjie Wen , Yiming Zhang , Xiufeng Yang , Yang Cai , Sen Chen , Xiao Hou , Yi Wu

The response of solid rocket motors (SRMs) to high-speed fragment impacts is crucial for their safety design and operational use in scenarios such as rocket launches and space applications. The visualized Burn to Violent Reaction (BVR) test is used to observe intense reactions induced by high-speed projectile impacts. Employing a two-stage light gas gun and optical diagnostic techniques including high-speed schlieren imaging and direct photography, the impact-induced deflagration/explosion behavior, and reaction growth behavior were investigated. The damage mechanisms of the casing and propellant samples were assessed, and the reaction growth and afterburn effects of the impact-induced fragment cloud were quantitatively analyzed. The results indicate that the ignition delay time is inversely correlated with the impact velocity, decreasing from ms to μs scale. Across a wide range of velocities (1050–2058 m/s), higher projectile velocities induce more sustained and vigorous combustion reactions within the propellant. Furthermore, increasing the propellant air gap to 7.8 cm does not trigger further reactions under the studied configurations. The reaction mechanisms are closely linked to the characteristics of the fragment cloud induced by the impact. The developed Smoothed Particle Hydrodynamics (SPH) method, incorporating material constitutive models, ignition criteria, and reaction growth models, was used to study the influence of projectile velocity on the reaction mechanisms. The simulation results were compared with experimental data, demonstrating satisfactory accuracy.

固体火箭发动机（SRM）对高速碎片撞击的反应对其安全设计以及在火箭发射和太空应用等场景中的操作使用至关重要。可视化燃烧到剧烈反应（BVR）试验用于观察高速弹丸撞击引起的剧烈反应。利用两级光气枪和光学诊断技术（包括高速裂隙成像和直接摄影），研究了撞击诱发的爆燃/爆炸行为和反应生长行为。评估了外壳和推进剂样品的损坏机制，并定量分析了撞击诱发的碎片云的反应生长和后燃效应。结果表明，点火延迟时间与撞击速度成反比，从毫秒到微秒级递减。在较宽的速度范围（1050-2058 m/s）内，较高的弹丸速度会在推进剂内部引起更持久、更剧烈的燃烧反应。此外，在所研究的构型下，将推进剂气隙增大到 7.8 厘米也不会引发进一步的反应。反应机制与撞击引起的碎片云的特征密切相关。所开发的平滑粒子流体力学（SPH）方法结合了材料构成模型、点火标准和反应生长模型，用于研究弹丸速度对反应机制的影响。模拟结果与实验数据进行了比较，显示出令人满意的准确性。

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引用次数: 0

Low-velocity impact of castor oil-based rigid polyurethane foams: Experiments, microstructure effects and constitutive modelling 蓖麻油基硬质聚氨酯泡沫的低速冲击：实验、微观结构效应和构成模型

IF 5.1 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Impact Engineering

Pub Date : 2024-11-01 DOI: 10.1016/j.ijimpeng.2024.105156

Jacopo Lavazza , Qicheng Zhang , Charles de Kergariou , Gianni Comandini , Fernando Alvarez-Borges , Orestis L. Katsamenis , Wuge H. Briscoe , Jemma L. Rowlandson , Tulio Hallak Panzera , Fabrizio Scarpa

Rigid polyurethane foams (RPUFs) are widely used in impact protection applications due to their tunable mechanical properties. Recently, RPUFs derived from bio-based sources such as castor oil have been investigated as a greener and more sustainable alternative to replace fossil-based polyurethane foams. It is thus important to understand the mechanical response of these materials to low-velocity impact (LVI), which still needs to be explored. This study aims to fill this gap by evaluating the performance of three types of RPUFs developed from commercially available castor oil-based resins. Drop weight impact tests at different impact energies were performed to investigate the LVI characteristics of the foams. Furthermore, an extensive micro-computed tomography investigation was carried out to improve the understanding of the microstructure of RPUFs and how the composition of these porous materials affected the foam architecture and the macroscopic mechanical response. Finally, a constitutive relationship is proposed to describe and predict the materials’ response at different impact energies.

硬质聚氨酯泡沫（RPUF）因其可调整的机械性能而被广泛应用于冲击防护领域。最近，人们研究了从蓖麻油等生物来源提取的 RPUF，认为这是一种更环保、更可持续的替代品，可以取代化石基聚氨酯泡沫。因此，了解这些材料对低速冲击（LVI）的机械响应非常重要，这一点仍有待探索。本研究旨在通过评估利用市售蓖麻油基树脂开发的三种 RPUF 的性能来填补这一空白。研究人员在不同的冲击能量下进行了落重冲击试验，以研究泡沫的 LVI 特性。此外，还进行了广泛的微观计算机断层扫描研究，以加深对 RPUF 微观结构以及这些多孔材料的成分如何影响泡沫结构和宏观机械响应的了解。最后，提出了一种构成关系来描述和预测材料在不同冲击能量下的响应。

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引用次数: 0