International Journal of Mechanical Sciences最新文献_第4页

Multi-modal response control with multiple suspension-type tuned vibration absorbers 多悬挂式调谐减震器的多模式响应控制

IF 7.1 1区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Mechanical Sciences

Pub Date : 2024-10-17 DOI: 10.1016/j.ijmecsci.2024.109775

Ning Su , Cong Zeng , Zhaoqing Chen , Jing Bian , Yi Xia

Due to complicated excitations, engineering structures are often subjected to multi-modal responses. Considering the feasibility in practical installation on slender structures, multiple Suspension-type Tuned Vibration Absorbers (S-TVAs) are investigated for multi-modal response control. Firstly, parametric optimization of a single S-TVA for single-modal response control is investigated analytically. The issues regarding to the optimal tuning, static and dynamic performances, and installation location are addressed. Subsequently, an optimal design method for multi-modal response control with multiple S-TVAs is presented. Two aspects on the optimization strategy are discussed. Consequently, the optimization should be performed with an inverse modal order sequence. And, the modal information should be updated considering the S-TVA optimized in the previous step. Finally, the effectiveness of the presented optimal design method is validated through practical wind-induced response control on a slender chimney. The most unfavorable response can be suppressed up to 59.7 %, which is 47.8 % better than traditional single-modal control approach. Moreover, it is interesting to find that the practical overall control performance may not be achieved with more controlled modes intuitively. It is recommended to select from several practical cases determined by the presented optimal design method. Practical installation and feasibility are highly required to be considered in practice.

由于复杂的激励，工程结构经常会受到多模态响应的影响。考虑到在细长结构上实际安装的可行性，研究了用于多模态响应控制的多个悬挂式调谐减振器（S-TVA）。首先，对用于单模态响应控制的单个 S-TVA 的参数优化进行了分析研究。解决了有关优化调整、静态和动态性能以及安装位置的问题。随后，介绍了使用多个 S-TVA 进行多模式响应控制的优化设计方法。讨论了优化策略的两个方面。因此，优化应采用反模态顺序序列。此外，模态信息应根据上一步优化的 S-TVA 进行更新。最后，通过对细长烟囱进行实际的风致响应控制，验证了所提出的优化设计方法的有效性。最不利响应的抑制率可达 59.7%，比传统的单一模式控制方法高出 47.8%。此外，有趣的是，实际的整体控制性能可能无法直观地通过更多的控制模式来实现。建议从所提出的优化设计方法确定的几个实际案例中进行选择。实际安装和可行性是实践中必须考虑的重要因素。

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引用次数: 0

A direct method to identify Young’s moduli and boundary conditions of the heterogeneous material 确定异质材料杨氏模量和边界条件的直接方法

IF 7.1 1区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Mechanical Sciences

Pub Date : 2024-10-17 DOI: 10.1016/j.ijmecsci.2024.109777

Tian Xu , Murong Li , Zhen Wang , Yingda Hu , Shilun Du , Yong Lei

Identifying unknown Young’s moduli and boundary conditions of the heterogeneous material using locally observed boundary data is the inverse problem which is generally solved by iterative methods. In this paper, a two-steps direct method is proposed for the first time to solve this inverse problem without iterations. The proposed method innovatively decomposes the heterogeneous elasticity inverse problem to two homogeneous elasticity sub-inverse problems. The single-data and multiple-data based direct methods are applied to identify background Young’s modulus and displacement boundary conditions, while the Maxwell–Betti principle based direct method and the equivalent boundary force based direct method are proposed to identify Young’s moduli of inclusions. In addition, an optimal experimental design method with a goal-oriented criterion is proposed to improve the accuracy of the two-steps direct method by optimizing the force application positions in observation data acquisition. Both numerical and physical experiments were conducted. The results demonstrate the feasibility of the proposed two-steps direct method and its optimal experimental design method.

利用局部观测到的边界数据确定异质材料的未知杨氏模量和边界条件是逆问题，一般采用迭代法解决。本文首次提出了一种无需迭代的两步直接法来解决这一反问题。所提方法创新性地将异质弹性反问题分解为两个同质弹性子反问题。应用基于单数据和多数据的直接方法来确定背景杨氏模量和位移边界条件，同时提出了基于 Maxwell-Betti 原理的直接方法和基于等效边界力的直接方法来确定夹杂物的杨氏模量。此外，还提出了一种具有目标导向准则的优化实验设计方法，通过优化观测数据采集中的施力位置来提高两步直接法的精度。实验同时进行了数值和物理实验。结果证明了所提出的两步直接法及其优化实验设计方法的可行性。

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引用次数: 0

Origami folding pattern development for gossamer structures 花丝结构的折纸折叠图案开发

IF 7.1 1区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Mechanical Sciences

Pub Date : 2024-10-16 DOI: 10.1016/j.ijmecsci.2024.109780

Ivy Running , Carolina Wright , Robert J. Lang , Larry Howell , Spencer Magleby

Gossamer structures for satellites are large, thin deployable structures that are attractive for space applications because they can be stowed compactly for transportation and deployed to have large functional surface areas. Reflectarray antennas, in particular, are candidates for gossamer structures because they can be realized on thin membranes. However, the efficiency of reflectarray antennas decreases with any deviations from a flat plane, including those induced by plastically deformed creases. Rolling membranes can prevent some plastic deformation, but requires relative slipping between layers that are rolled together. In this work, we describe, analyze, and demonstrate two rolled configurations for deployable gossamer structures based on a combination of rolled and folded membranes and surrogate folds that allow for sliding between layers. Cuts and Step Hinges are used as surrogate folds. Step Hinges connect membranes while limiting slipping motion in a single direction and reducing wrinkling in the structure. The combination of folding, rolling, and sliding connections reduces plastic deformation while providing a highly efficient packing of the stowed form.

用于卫星的绞索结构是一种大型、薄型的可部署结构，对空间应用很有吸引力，因为这种结构可以紧凑地装载运输，部署后具有较大的功能表面积。特别是反射阵列天线，由于可以在薄膜上实现，因此是索纱结构的候选者。然而，反射阵列天线的效率会随着平面偏差（包括塑性变形褶皱引起的偏差）而降低。卷膜可以防止一些塑性变形，但需要在卷在一起的各层之间进行相对滑动。在这项工作中，我们描述、分析并演示了两种可部署格萨姆结构的卷曲配置，其基础是卷曲和折叠膜以及允许层间滑动的替代褶皱的组合。切口和阶梯铰链被用作替代褶皱。阶梯铰链将薄膜连接起来，同时限制了单一方向的滑动运动，减少了结构中的褶皱。折叠、滚动和滑动连接的组合可减少塑性变形，同时提供高效的收纳包装。

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引用次数: 0

Nonlinear mechanics of horseshoe microstructure-based lattice design 基于非线性力学的马蹄形微结构晶格设计

IF 7.1 1区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Mechanical Sciences

Pub Date : 2024-10-16 DOI: 10.1016/j.ijmecsci.2024.109781

Yuwu Zhang , Minghao Li , Zizhen Qi , Rong Chen , Yuliang Lin , Shunze Cao , Xiangcheng Li , Ruitao Tang , Huanming Chen

Enhancing buffering capacity, flexibility, and energy absorption to withstand large deformations in structure remains a challenge. Bio-inspired horseshoe lattice structures, with their curved trusses, exhibit distinct mechanical characteristics compared to conventional metamaterials. However, their mechanical properties under in-plane compression have been rarely explored. This study characterised and modelled three types of novel 3D-printed horseshoe lattice structures, totalling 12 configurations, with unit cell geometry varying based on cell-wall angles ranging from 120°to 210°. The implementation of the FE simulation based on the three-network viscoplastic (TNV) model showed good agreement with the experiments. The results demonstrated that the cell-wall angle in the geometry and the cross-lap joint topology were significantly associated with the failure mechanism of the unit cell and the overall non-linear mechanical behaviour. Increasing the cell-wall angles can prevent beams from failing due to bending and buckling fractures, facilitate the initiation of internal contacts and stretching during in-plane compression. This reveals a configurable mechanism where the flexibility and stability of the lattice structure can trigger strain hardening, resulting in an increase in load-bearing capacity. The sensitivity to strain hardening varies depending on the order of cross-laps within the topology. A colour-pattern tracking method was employed to monitor the progressive stabilisation of lattice structures, and offering a novel approach for the future design of flexible, configurable, and programmable horseshoe-based lattice structures.

提高缓冲能力、灵活性和能量吸收能力以承受结构的巨大变形仍然是一项挑战。与传统超材料相比，受生物启发的马蹄形晶格结构及其弧形桁架表现出独特的机械特性。然而，它们在平面压缩下的机械特性却鲜有研究。本研究对三种新型三维打印马蹄形晶格结构（共 12 种配置）进行了表征和建模，其单元格几何形状根据单元格壁角度的不同而变化，角度范围从 120° 到 210°。基于三网络粘塑性（TNV）模型的 FE 仿真结果与实验结果吻合。结果表明，几何形状中的晶胞壁角度和交叉搭接拓扑结构与单元晶胞的失效机制和整体非线性力学行为有显著关联。增大单元壁角度可以防止梁因弯曲和屈曲断裂而失效，促进内部接触的启动和平面压缩过程中的拉伸。这揭示了一种可配置的机制，即晶格结构的灵活性和稳定性可引发应变硬化，从而提高承载能力。对应变硬化的敏感性因拓扑结构中交叉搭接的顺序而异。我们采用了一种颜色模式跟踪方法来监测晶格结构的逐步稳定，为未来设计灵活、可配置和可编程的马蹄形晶格结构提供了一种新方法。

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引用次数: 0

Out-of-plane energy absorption of 3D printed basalt-fiber-reinforced hierarchical honeycomb composite 三维打印玄武岩纤维增强分层蜂窝复合材料的平面外能量吸收

IF 7.1 1区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Mechanical Sciences

Pub Date : 2024-10-16 DOI: 10.1016/j.ijmecsci.2024.109784

Luqing Hua , Lining Ding , Xin Wang , Siheng Zeng , Huang Huang , Xunmei Liang , Zhishen Wu

This work presents a new type of hierarchical triangular honeycomb created by iteratively replacing each vertex of conventional hexagonal cells with a smaller equilateral triangle. The combination of green and recyclable short basalt-fiber-reinforced composite with advanced additive manufacturing technology makes it possible to design and fabricate the 3D printed hierarchical triangular honeycomb composites with exceptional mechanical properties for energy absorption applications. Out-of-plane quasi-static compression tests were performed on the 3D printed hierarchical honeycomb composite to investigate the compressive response and deformation behaviour of hierarchical triangular honeycombs. Parametric studies were conducted using ABAQUS/Explicit finite element code to study the effects of structural hierarchy and triangular cell size on mechanical properties and energy absorption of 3D printed hierarchical triangular honeycombs. The result revealed that the 3D printed hierarchical triangular honeycomb composite experienced a large and stable plastic deformation to densification without fracture failure resulting in excellent energy absorption. The second level triangular honeycomb composite exhibited the most promising mechanical properties. After optimization of the triangular cell size, the mean crushing force and specific energy absorption of the second level triangular honeycomb composite were about 1.7 times and 2.0 times those of the conventional hexagonal honeycomb composite. Compared to other typical hierarchical honeycombs, the proposed hierarchical triangular honeycomb composite exhibited higher plateau stress and larger densification strain, thus providing some insights in designing lightweight, recyclable and sustainable 3D printed honeycomb composites with superior mechanical properties.

这项研究提出了一种新型分层三角形蜂窝材料，它是通过用一个较小的等边三角形迭代替换传统六边形单元的每个顶点而产生的。绿色、可回收的短玄武岩纤维增强复合材料与先进的增材制造技术相结合，使设计和制造具有优异机械性能的 3D 打印分层三角形蜂窝复合材料成为可能，并可用于能量吸收应用。对三维打印分层蜂窝复合材料进行了平面外准静态压缩试验，以研究分层三角形蜂窝的压缩响应和变形行为。使用 ABAQUS/Explicit 有限元代码进行了参数研究，以研究结构层次和三角形单元尺寸对三维打印分层三角形蜂窝的力学性能和能量吸收的影响。结果表明，3D 打印分层三角形蜂窝复合材料在致密化过程中经历了较大且稳定的塑性变形，没有断裂失效，因而具有良好的能量吸收能力。第二层三角形蜂窝复合材料表现出最有前途的机械性能。优化三角形单元尺寸后，第二层三角形蜂窝复合材料的平均压碎力和比能量吸收分别是传统六边形蜂窝复合材料的 1.7 倍和 2.0 倍。与其他典型的分层蜂窝相比，所提出的分层三角形蜂窝复合材料表现出更高的高原应力和更大的致密化应变，从而为设计具有优异力学性能的轻质、可回收和可持续的三维打印蜂窝复合材料提供了一些启示。

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引用次数: 0

An electro-thermo-mechanical coupling phase-field model of defect evolution induced by electromigration in interconnects 互连器件中电迁移诱发缺陷演变的电-热-机械耦合相场模型

IF 7.1 1区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Mechanical Sciences

Pub Date : 2024-10-16 DOI: 10.1016/j.ijmecsci.2024.109792

Xin-Wei Wu, Mingyang Chen, Liao-Liang Ke

In this paper, the defect evolution caused by electromigration induced surface diffusion in interconnects is investigated using a newly-developed electro-thermo-mechanical coupling phase-field model. The Joule heat and its resulting thermomigration are included into the phase-field model. The governing equation of the phase-field is solved by semi-implicit spectral methods and the accompanied governing equations of applied physics fields are solved by finite volume methods. Comparative investigation into defect evolution with and without the influence of Joule heating is conducted. It is deduced that thermomigration facilitates local elongation of the defect in the “current crowding” region and exerts a substantial influence on the defect morphological evolution. Subsequently, the effect of the inclination angle of the electric field on the void morphology evolution and crack propagation is discussed. We find that the defect achieves the largest characteristic length when the electric field direction is perpendicular to the uniaxial tension direction, implying a higher threat to the circuit safety. This study may help to deepen people's understanding of how the thermal effect functions in electromigration process and sheds light on different modes of defect evolution in interconnects.

本文采用新开发的电-热-机械耦合相场模型，研究了互连器件中由电迁移引起的表面扩散所导致的缺陷演变。相场模型中包括焦耳热及其产生的热迁移。相场的控制方程采用半隐谱法求解，应用物理场的伴随控制方程采用有限体积法求解。对有焦耳加热影响和无焦耳加热影响的缺陷演变进行了比较研究。结果表明，热迁移促进了 "电流拥挤 "区域内缺陷的局部伸长，并对缺陷的形态演变产生了重大影响。随后，讨论了电场倾角对空隙形态演变和裂纹扩展的影响。我们发现，当电场方向垂直于单轴拉伸方向时，缺陷的特征长度最大，这意味着对电路安全的威胁更大。这项研究有助于加深人们对热效应如何在电迁移过程中发挥作用的理解，并揭示了互连器件中缺陷演化的不同模式。

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引用次数: 0

Novel method to assess anisotropy in formability using DIC 利用 DIC 评估成形性各向异性的新方法

IF 7.1 1区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Mechanical Sciences

Pub Date : 2024-10-16 DOI: 10.1016/j.ijmecsci.2024.109782

Ebrahim Seidi , Scott F. Miller , Farnaz Kaviari , Lu Huang , Thomas B. Stoughton

In this study, a novel technique was developed to identify localized neck of a tensile sample based on the curvature of the surface that is expected to work with any metal in which a localized neck forms prior to fracture. Moreover, a MATLAB-based computational tool has been developed to conduct advanced mathematical computations and numerical analysis on data generated from uniaxial tensile test of DP980 steel coupled with Digital Image Correlation (DIC) based on the novel curvature method. The presented curvature technique is a geometry-based approach that uses the specimen's surface profile and groove geometry to detect localized necking, avoiding the limitations of strain-based methods in distinguishing between localized and diffuse necking. A detailed analysis was conducted on the accuracy of the onset and anisotropy of localized neck. The results of the study revealed that specimens fabricated with 30-degree orientation with respect to the Rolling Direction (RD) of the sheet metal, exhibit a higher level of total strain at the onset of the localized necking, indicating the influence of anisotropy on the material's behavior for DP980. Moreover, consistent R-values were observed among specimens with the same orientation with respect to the RD, exhibiting a rising trend of R-value for orientations from zero to 60-degree, followed by a decrease from 60 to 90-degree. Furthermore, the results exhibited a negative linear relationship between R-values and the magnitude of thinning strain.

在本研究中，开发了一种新技术，可根据表面曲率识别拉伸样品的局部颈部，该技术预计可用于在断裂前形成局部颈部的任何金属。此外，还开发了一种基于 MATLAB 的计算工具，用于对 DP980 钢单轴拉伸试验产生的数据进行高级数学计算和数值分析，并根据新颖的曲率方法结合数字图像相关性 (DIC)。所介绍的曲率技术是一种基于几何形状的方法，它利用试样的表面轮廓和沟槽几何形状来检测局部颈缩，避免了基于应变的方法在区分局部颈缩和弥散颈缩方面的局限性。研究人员对局部缩颈的发生和各向异性的准确性进行了详细分析。研究结果表明，与板材轧制方向（RD）成 30 度的试样在局部缩颈开始时表现出更高的总应变水平，这表明各向异性对 DP980 材料行为的影响。此外，在相对于 RD 具有相同取向的试样中观察到了一致的 R 值，从零度到 60 度取向的 R 值呈上升趋势，而从 60 度到 90 度取向的 R 值则呈下降趋势。此外，结果显示 R 值与变薄应变的大小呈负线性关系。

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引用次数: 0

Neural network-augmented differentiable finite element method for boundary value problems 边界值问题的神经网络增强可微有限元法

IF 7.1 1区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Mechanical Sciences

Pub Date : 2024-10-16 DOI: 10.1016/j.ijmecsci.2024.109783

Xi Wang , Zhen-Yu Yin , Wei Wu , He-Hua Zhu

Classical numerical methods such as finite element method (FEM) face limitations due to their low efficiency when addressing large-scale problems. As a novel paradigm, the physics-informed neural network (PINN) has demonstrated significant potential to solve partial differential equations. However, conventional PINNs utilize meshless control at discrete sampling points, which limits their ability to effectively handle complex boundaries. Moreover, catastrophic failure may occur in the deep energy method (DEM, a specific type of PINN). To handle these challenges, this study proposes a Neural Network-augmented Differentiable Finite Element Method (NNDFEM) by combining PINN and finite element approximation. In NNDFEM, the neural network backend solely predicts nodal variables. Derivatives and complex boundary conditions can be well handled by the finite element frontend. The governing equation over the domain, Dirichlet, and Neumann boundary conditions are directly enforced on the finite element frontend. Thus, losses of boundary conditions in PINN are rendered unnecessary. The overfitting problem in DEM is also significantly mitigated. Fully connected neural network (FCNN), modified FCNN, and graph-convolutional network are tested as backends. NNDFEM circumvents nodal force calculation and matrix assembly in FEM. Functional losses of linear elasticity, finite strain nonlinear elasticity, heat conduction, and flow in porous media are validated. A systematic exploration unveils the role of 3D finite element mesh. For large-scale problems, a multi-fidelity learning strategy is employed. Thus, the three-dimensional case with over three million degrees of freedom trains well in two minutes. Benefiting from the fast inference of the neural network backend, the forward pass is 8,550 times faster than FEM.

有限元法（FEM）等经典数值方法在解决大规模问题时由于效率较低而受到限制。作为一种新型范例，物理信息神经网络（PINN）在求解偏微分方程方面展现出巨大潜力。然而，传统的 PINN 采用离散采样点的无网格控制，这限制了其有效处理复杂边界的能力。此外，深能量法（DEM，一种特定类型的 PINN）可能会出现灾难性故障。为了应对这些挑战，本研究结合 PINN 和有限元近似，提出了神经网络增强可微有限元法（NNDFEM）。在 NNDFEM 中，神经网络后台只预测节点变量。有限元前端可以很好地处理衍生变量和复杂的边界条件。有限元前端直接执行域上的支配方程、狄里希勒和诺伊曼边界条件。因此，无需在 PINN 中损失边界条件。DEM 中的过拟合问题也得到了显著缓解。全连接神经网络（FCNN）、改进的 FCNN 和图卷积网络作为后端进行了测试。NNDFEM 避免了有限元中的节点力计算和矩阵装配。验证了线性弹性、有限应变非线性弹性、热传导和多孔介质流动的功能损失。系统探索揭示了三维有限元网格的作用。对于大型问题，采用了多保真度学习策略。因此，具有 300 多万自由度的三维案例在两分钟内就能训练有素。得益于神经网络后台的快速推理，前向传递比有限元网格快 8550 倍。

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引用次数: 0

Fragility analysis of tubular structures based on local-buckling driving variables 基于局部屈曲驱动变量的管状结构脆性分析

IF 7.1 1区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Mechanical Sciences

Pub Date : 2024-10-13 DOI: 10.1016/j.ijmecsci.2024.109776

Scarlet K. Montilla , Rúbia M. Bosse , Gustavo M.S. Gidrão , André T. Beck , Ricardo A. Picón , JiePeng Liu , Yongtao Bai , Julio Florez-Lopez

Performance-Based Earthquake Engineering (PBEE) is computationally demanding, due to the multiple high-fidelity nonlinear dynamic structural response analyses required to compute fragility curves. Local buckling of tubular steel structures is not properly characterized by typical Engineering Demand Parameters (EDPs) such as story drifts or plastic rotation angles. Targeting the two issues above, in this manuscript we propose using state variables based on Lumped Damage Mechanics (LDM) to characterize Local Buckling (LB) in PBEE. Hence, we propose an efficient and innovative procedure for the fragility analysis of complex tubular structures prone to fail due to local buckling. Moreover, local buckling produces a loss of stiffness, with loads transferred to intact or to less-damaged elements. Eventually, the structure forms a global collapse mechanism. Herein, we show how to identify the most likely global collapse mechanism in non-symmetrical tubular structures subjected to random seismic loading. This involves evaluating damage indices in different elements and their correlation, as well as identifying the combination of LB failures that are more likely to form a global collapse mechanism. Fragility curves characterizing the onset of LB at individual elements, and the most likely global collapse mechanism, are constructed. A simple frame structure is addressed, where the accuracy of the LB-LDM model is checked against experimental results. Another case study involving a non-symmetric tubular wharf illustrates the search for the most likely global collapse mechanism, and the derivation of its fragility function.

基于性能的地震工程（PBEE）对计算要求很高，因为需要进行多种高保真非线性动态结构响应分析来计算脆性曲线。典型的工程需求参数（EDP）（如楼层漂移或塑性旋转角）无法正确描述管状钢结构的局部屈曲。针对上述两个问题，我们在本手稿中建议使用基于成块损伤力学（LDM）的状态变量来描述 PBEE 中的局部屈曲（LB）。因此，我们为容易因局部屈曲而失效的复杂管状结构的脆性分析提出了一种高效、创新的程序。此外，局部屈曲会导致刚度损失，荷载会转移到完好或损伤较小的构件上。最终，结构会形成整体坍塌机制。在本文中，我们展示了如何确定在随机地震荷载作用下的非对称管状结构中最可能的整体坍塌机制。这包括评估不同构件的损伤指数及其相关性，以及识别更有可能形成整体倒塌机制的 LB 故障组合。构建的脆性曲线描述了单个构件的枸杞溃散起始点以及最有可能的整体坍塌机制。针对一个简单的框架结构，根据实验结果检验了 LB-LDM 模型的准确性。另一个案例研究涉及一个非对称管状码头，说明了如何寻找最可能的整体坍塌机制，并推导出其脆性函数。

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引用次数: 0

New hot workability prediction method under non-constant deformation conditions 非恒定变形条件下的新型热加工性能预测方法

IF 7.1 1区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Mechanical Sciences

Pub Date : 2024-10-13 DOI: 10.1016/j.ijmecsci.2024.109778

Shuo Guo , Caiyi Liu , Shicheng Liang , Silvia Barella , Yan Peng , Andrea Gruttadauria , Marco Belfi , Sha Ouyang , De Li , Hamid Reza Karimi , Carlo Mapelli

The deformation conditions of metallic materials constantly change during forming and manufacturing technology. The thermomechanical processing theory cannot be applied to non-constant deformation conditions. The hot workability is a manifestation of the deformation conditions that affect the microstructure. This paper proposes a new prediction method based on artificial intelligence, considering the combined effect of microstructure state and deformation conditions. The hot deformation experiments under constant and non-constant deformation conditions validate the proposed method. Dynamic variation in deformation conditions significantly affects the hot workability. The findings indicate that reasonable control of the dynamic variation in deformation conditions during thermomechanical processing is conducive to improving the hot workability, providing new ways for equipment upgrading and process parameter optimization of some thermal processing technologies.

金属材料的变形条件在成形和制造技术过程中不断变化。热机械加工理论无法应用于非恒定变形条件。热加工性能是变形条件影响微观结构的一种表现形式。本文提出了一种基于人工智能的新预测方法，考虑了微观结构状态和变形条件的综合影响。恒定和非恒定变形条件下的热变形实验验证了所提出的方法。变形条件的动态变化极大地影响了热加工性能。研究结果表明，合理控制热机械加工过程中变形条件的动态变化有利于提高热加工性能，为一些热加工技术的设备升级和工艺参数优化提供了新的途径。

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引用次数: 0