International Journal of Non-Linear Mechanics最新文献_第6页

Isolation performances of combined system with large amplitude nonlinearity and dynamic vibration absorber 大振幅非线性与动态吸振器组合系统的隔振性能

IF 3.2 3区工程技术 Q2 MECHANICS

International Journal of Non-Linear Mechanics

Pub Date : 2025-08-22 DOI: 10.1016/j.ijnonlinmec.2025.105243

Yuntian Zhang, Xiuting Sun, Jian Xu

The vibration isolation performance of a combined vibration isolation (CVI) system incorporating triple quasi-zero stiffness (TQZS) and a dynamic vibration absorber (DVA) is investigated in this paper. The influences of mass ratio and static characteristics on the CVI system are analyzed, and the superior isolation performances of the CVI system compared to both the basic TQZS system and the QZS-DVA system are validated. The coupled effects of enhanced vibration absorption and weakened achievable optimal static characteristics, resulting from increased mass ratio, on the CVI system’s isolation performance are explored. Significant advantages of the CVI system are observed, not only compared to traditional QZS-DVA systems, but also compared to high-order single QZS-DVA systems at larger excitation amplitudes. Greater robustness in the tuning frequency is demonstrated by the CVI system when compared to the QZS-DVA system, leading to effective adaptation across a wider range of excitation amplitudes and reducing the reliance on adaptive tuning. An upward shift of the Pareto frontiers is observed with increasing mass ratio, resulting in a degradation of the achievable static characteristics of the CVI system. Improved robustness can be maintained by ensuring a low restoring force at the zero-stiffness point located away from the equilibrium, when the TQZS characteristics are selected from the Pareto frontiers.

研究了三准零刚度（TQZS）和动态吸振器（DVA）组合隔振系统的隔振性能。分析了质量比和静态特性对CVI系统的影响，验证了CVI系统相对于基本TQZS系统和QZS-DVA系统具有优越的隔震性能。探讨了质量比增大导致的吸振增强和可达到的最优静态特性减弱对CVI系统隔振性能的耦合影响。CVI系统不仅与传统的QZS-DVA系统相比，而且与大激励幅值的高阶单QZS-DVA系统相比，都具有显著的优势。与QZS-DVA系统相比，CVI系统在调谐频率方面具有更强的鲁棒性，可以有效地适应更大范围的激励幅度，并减少对自适应调谐的依赖。随着质量比的增加，观察到帕累托边界向上移动，导致CVI系统可实现静态特性的退化。当从Pareto边界中选择TQZS特征时，可以通过确保在远离平衡的零刚度点处的低恢复力来保持改进的鲁棒性。

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引用次数: 0

Nonlinear internal waves and turbulent mixing in a three-layer stratified fluid in a closed reservoir 封闭储层中三层层状流体的非线性内波与湍流混合

IF 3.2 3区工程技术 Q2 MECHANICS

International Journal of Non-Linear Mechanics

Pub Date : 2025-08-20 DOI: 10.1016/j.ijnonlinmec.2025.105241

Alexander Chesnokov , Valery Liapidevskii , Alexander Kazakov

We apply a one-dimensional nonlinear long-wave Boussinesq-type model, supplemented with friction/force terms, to describe the evolution of internal waves in a three-layer fluid filling a closed reservoir. The model takes into account the effects of dispersion and turbulent mixing. The outer homogeneous layers of the fluid are governed by the Green–Naghdi-type equations. The depth-averaged shallow water equations describe the flow in the intermediate hydrostatic layer. A simple law of vertical mixing governs the interaction of these layers during the development of the Kelvin–Helmholtz instability. We model internal seiches and their transformation into nonlinear wave trains in a quasi-two-layer fluid generated by a tilted tank suddenly returned to the untilted configuration. Comparison of the calculation results for different ratios of layer thicknesses and tank tilt angles shows good agreement with known experimental data. We also consider the evolution of wind-driven internal waves and show that the results obtained from the model align with direct numerical simulations.

本文采用一维非线性长波boussinesq型模型，辅以摩擦/力项，描述了封闭储层三层流体内波的演化。该模型考虑了色散和湍流混合的影响。流体的外均匀层由green - naghdi型方程控制。水深平均浅水方程描述了中间静水层的流动。在开尔文-亥姆霍兹不稳定性的发展过程中，垂直混合的简单规律支配着这些层的相互作用。我们模拟了由倾斜的储罐突然恢复到未倾斜状态所产生的准两层流体中的内塞及其转化为非线性波列的过程。对不同层厚比和不同倾斜角的计算结果进行了比较，结果与已知实验数据吻合较好。我们还考虑了风驱动内波的演变，并表明从模型得到的结果与直接数值模拟一致。

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引用次数: 0

Modal interactions between a linear oscillator and a nonlinear absorber: multiscale energy transfers 线性振荡器和非线性吸收器之间的模态相互作用：多尺度能量传递

IF 3.2 3区工程技术 Q2 MECHANICS

International Journal of Non-Linear Mechanics

Pub Date : 2025-08-19 DOI: 10.1016/j.ijnonlinmec.2025.105244

Lan Huang, Shufeng Lu, Wensai Ma

In aerospace engineering, considerable attention has been given to the use of a nonlinear energy sink (NES) as an efficient passive control device. This paper uses the Complexification-Averaging/Geometric Singular Perturbation Theory (CX-A/GSPT) to investigate the multiscale energy transfers in a forced two-DOF system coupled to a grounded NES (GNES) with both nonlinear grounded stiffness and damping. Due to the coexistence of fundamental resonance and internal resonance in the system, complex modal interactions occur between the linear oscillator (LO) and the GNES. In addition, the ratio of the mass of the GNES and the LO can be seen as a perturbation. This may lead to the occurrence of multiscale dynamics and energy transfers in the system. By using the CX-A method, the slow flow equations of the system can be obtained. Further application of GSPT can obtain the critical manifold that is equivalent to the so-called slow invariant manifold (SIM). With different values of nonlinear grounded stiffness and damping, the critical manifolds have different structures. These critical manifolds can capture diverse types of system responses. Moreover, Hilbert-Huang transform (HHT) is used to analyze the time-frequency-energy relationship of the system response. With different parameters, the instantaneous frequencies of the responses of the LO and GNES show a completely different change. The Hilbert spectra confirm the occurrence of complex modal interactions and different time-scale energy transfers in the system.

在航空航天工程中，非线性能量阱作为一种高效的被动控制装置受到了广泛的关注。本文采用复化平均/几何奇异摄动理论（CX-A/GSPT）研究了具有非线性接地刚度和阻尼的双自由度系统的多尺度能量传递问题。由于系统中存在基共振和内共振，线性振荡器（LO）与GNES之间存在复杂的模态相互作用。此外，GNES和LO的质量之比可以看作是一种扰动。这可能导致系统中出现多尺度动力学和能量转移。利用CX-A方法，可以得到系统的慢流方程。进一步应用GSPT可以得到等效于所谓慢不变流形（SIM）的临界流形。在不同的非线性接地刚度和阻尼值下，临界流形具有不同的结构。这些关键流形可以捕获不同类型的系统响应。利用Hilbert-Huang变换（HHT）分析了系统响应的时频能量关系。在不同的参数下，LO和GNES响应的瞬时频率表现出完全不同的变化。希尔伯特谱证实了系统中存在复杂模态相互作用和不同时标能量传递。

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引用次数: 0

Transient dynamics of a polynomial stiffness nonlinear vibration absorber: Theoretical and numerical investigations 多项式刚度非线性减振器的瞬态动力学：理论与数值研究

IF 3.2 3区工程技术 Q2 MECHANICS

International Journal of Non-Linear Mechanics

Pub Date : 2025-08-18 DOI: 10.1016/j.ijnonlinmec.2025.105242

Xiaoxin Dai , Xiaojun Wei , Lihua Tang

This paper presents thorough theoretical and numerical investigations of transient dynamics of a linear primary system coupled with a polynomial stiffness nonlinear vibration absorber (PNVA), recently proposed by some of the authors. The PNVA incorporates positive linear and cubic stiffnesses and negative quadratic stiffness, with properly chosen coefficients to ensure the nonlinear restoring force function has only one equilibrium point at the origin. Distinct dynamic behaviors of a PNVA, such as the potential presence of two folds in a slow invariant manifold (SIM) curve, are revealed, highlighting a clear contrast to the behavior of a traditional nonlinear energy sink (NES). A design approach for a PNVA is proposed such that its energy dissipation efficiency and robustness against both structural frequency and input energy variations are simultaneously optimized. Subsequently, a comprehensive performance comparison of PNVAs, cubic NESs, bistable NESs, and traditional tuned mass dampers under free decay vibration induced by initial conditions is conducted. It is concluded that the proposed PNVA exhibits the best robustness against structural frequency detuning and relatively good energy dissipation efficiency and robustness against input energy variation. The PNVA offers an effective solution to the challenge of robust vibration mitigation.

本文对一些作者最近提出的线性一次系统耦合多项式刚度非线性吸振器（PNVA）的瞬态动力学进行了深入的理论和数值研究。PNVA结合了正线性刚度和正三次刚度以及负二次刚度，通过适当选择系数来保证非线性恢复力函数在原点只有一个平衡点。揭示了PNVA的独特动态行为，例如在慢不变流形（SIM）曲线中可能存在两个折叠，突出了与传统非线性能量汇（NES）行为的明显对比。提出了一种同时优化PNVA的能量耗散效率和对结构频率和输入能量变化的鲁棒性的设计方法。随后，对PNVAs、三次NESs、双稳态NESs和传统调谐质量阻尼器在初始条件诱导的自由衰减振动下的性能进行了综合比较。结果表明，该方法对结构频率失谐具有较好的鲁棒性，对输入能量变化具有较好的能量耗散效率和鲁棒性。PNVA提供了一种有效的解决方案，以应对鲁棒减振的挑战。

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引用次数: 0

A compactor-soil coupling model considering mechanical inertia and its delayed feedback active suspension control 考虑机械惯量的压实土耦合模型及其延迟反馈主动悬架控制

IF 3.2 3区工程技术 Q2 MECHANICS

International Journal of Non-Linear Mechanics

Pub Date : 2025-08-18 DOI: 10.1016/j.ijnonlinmec.2025.105245

Dong Feng

Compactors have been widely employed in civil engineering projects, including pavement construction, railway embankments, and dam foundations. To investigate compactor-soil interaction dynamics, researchers have developed numerous dynamic models to optimize compaction efficiency. Traditional modeling approaches typically neglected the mechanical inertia of compactor suspension systems for simplification purposes. However, this simplification underestimates the filtering effect of suspension mass on vibration excitation, resulting in compromised phase delay characterization and high-frequency dynamic response prediction. These limitations adversely affect both control strategy effectiveness and model prediction accuracy. To overcome these limitations, this study develops an innovative compactor-soil coupling model incorporating mechanical inertia to more accurately simulate compactor dynamics. The research systematically examines the dynamic differences introduced by inertia consideration. The results reveal that mechanical inertia significantly prolongs the transient response time. Specifically, the steady-state times of the frame increases from 8.03 s to 55.78 s, while the steady-state times of the drum rises from 4.57 s to 27.06 s. Consequently, delayed feedback active suspension control is implemented to effectively suppress system oscillations, reducing the steady-state times to 14.31 s (frame) and 7.67 s (drum) using a displacement gain equal to three times the frame stiffness. Comparative analyses demonstrate the superior adaptability of the proposed coupling model in characterizing compactor dynamic responses. This advanced model not only provides practical solutions for enhancing vibration isolation and compaction quality but also establishes a theoretical foundation for developing next-generation intelligent compaction systems.

压实机已广泛应用于土木工程项目，包括路面施工、铁路路堤和大坝基础。为了研究压实机与土壤的相互作用动力学，研究人员开发了许多动态模型来优化压实效率。传统的建模方法通常为了简化而忽略了压路机悬挂系统的机械惯性。然而，这种简化低估了悬架质量对振动激励的滤波作用，导致相位延迟表征和高频动态响应预测受到损害。这些限制对控制策略的有效性和模型预测精度都有不利影响。为了克服这些限制，本研究开发了一种创新的压实机-土壤耦合模型，该模型考虑了机械惯性，以更准确地模拟压实机的动力学。本研究系统地考察了惯性考虑所带来的动态差异。结果表明，机械惯量显著延长了瞬态响应时间。其中，车架的稳态时间从8.03 s增加到55.78 s，滚筒的稳态时间从4.57 s增加到27.06 s。因此，延迟反馈主动悬架控制实现有效抑制系统振荡，减少稳态时间为14.31秒（帧）和7.67秒（鼓）使用位移增益等于三倍的框架刚度。对比分析表明，所提出的耦合模型在描述压实机动态响应方面具有较好的适应性。这种先进的模型不仅为提高隔振和压实质量提供了实用的解决方案，而且为开发下一代智能压实系统奠定了理论基础。

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引用次数: 0

Comparative analysis of soft-impact and Gent models used in dielectric membrane based vibro-impact energy harvesting 介质膜振动冲击能量收集中软冲击模型与Gent模型的对比分析

IF 3.2 3区工程技术 Q2 MECHANICS

International Journal of Non-Linear Mechanics

Pub Date : 2025-08-18 DOI: 10.1016/j.ijnonlinmec.2025.105238

Sounak Chakraborty, Santanu Das

Soft-impact and Gent models are analysed and a Duffing like approximation corresponding to the Gent model is derived to obtain a connection between them. The approximate model highlights the underlying nature of the nonlinearity present in the system and establishes a relationship between the Gent and the soft-impact model. Using the approximate non-composite model, the membrane parameters corresponding to the soft-impact model are calculated analytically. The calculated parameters are used to compare the dynamical responses, membrane voltage variation and the harvested power corresponding to the Gent, the approximate and the soft-impact models. A series of bifurcation studies, of and around the period-1 oscillations, with respect to the excitation parameters are performed by employing the approximate model. The effect of energy harvesting on bifurcation structure is also studied. In conclusion, the applicability and the limitations of the hard-impact, the soft-impact and approximate models are analysed taking the stress based Gent model as the standard.

分析了软冲击模型和根特模型，并推导了与根特模型相对应的Duffing近似，以获得两者之间的联系。近似模型强调了系统中存在的非线性的潜在性质，并建立了根特模型和软冲击模型之间的关系。采用近似非复合模型，对软冲击模型对应的膜参数进行了解析计算。利用计算得到的参数，比较了根特模型、近似模型和软冲击模型所对应的动力响应、膜电压变化和收获功率。采用近似模型，对激励参数进行了周期1振荡及其周围的一系列分岔研究。研究了能量收集对分岔结构的影响。最后，以应力为基础的Gent模型为标准，分析了硬冲击模型、软冲击模型和近似模型的适用性和局限性。

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引用次数: 0

Stochastic reliability optimization of a controlled nonlinear energy sink under random excitation using GA-GRBFNN algorithm 基于GA-GRBFNN算法的随机激励下可控非线性能量池随机可靠性优化

IF 3.2 3区工程技术 Q2 MECHANICS

International Journal of Non-Linear Mechanics

Pub Date : 2025-08-15 DOI: 10.1016/j.ijnonlinmec.2025.105239

Mingzhi Lin , Wei Li , Dongmei Huang , Natasa Trisovic

Designing a control strategy to enhance the reliability of mechanical systems under random loads is crucial for maintaining system stability, resilience, performance, and safety. The primary challenge lies in optimizing the controller parameters while determining the reliability indexes. To overcome this difficulty, we have developed a novel intelligent algorithm to estimate optimal reliability of a kind of mechanical systems subjected to random loads by using a time-delay controller. This algorithm integrates a Gaussian Radial Basis Function Neural Network (GRBFNN) into a Genetic Algorithm (GA), taking the reliability function with unknown controlling parameters as the objective function, meanwhile the Backward Kolmogorov (BK) equation governing the reliability function with boundary condition and initial condition as constraints. In this algorithm, the neural network is employed to solve the BK equations at each iteration step of the GA to derive a fitness function, then the GA is utilized to obtain the optimal controlling parameters. Our algorithm enables the simultaneous optimization of implicit objectives and the solution of time-dependent BK equations. The influence of key parameters, such as population size, maximum iteration times in GA and the number of nodes in the neural network, on reliability performance is discussed in detail. The effectiveness of the proposed algorithm is testified through numerical comparisons and Monte Carlo simulations. The control strategy presented in this paper provides theoretical guidance to enhance reliability performance in mechanical engineering and shows great promise for practical applications.

设计一种控制策略来提高机械系统在随机载荷下的可靠性，对于保持系统的稳定性、弹性、性能和安全性至关重要。在确定可靠性指标的同时，对控制器参数进行优化是主要的挑战。为了克服这一困难，我们开发了一种新的智能算法，通过使用时滞控制器来估计随机负载下一类机械系统的最优可靠性。该算法将高斯径向基函数神经网络（GRBFNN）与遗传算法（GA）相结合，以控制参数未知的可靠性函数为目标函数，以边界条件和初始条件为约束的后向Kolmogorov （BK）方程来控制可靠性函数。在该算法中，利用神经网络在遗传算法的每个迭代步骤中求解BK方程，得到适应度函数，然后利用遗传算法获得最优控制参数。我们的算法能够同时优化隐式目标和求解随时间变化的BK方程。详细讨论了种群大小、遗传算法最大迭代次数和神经网络节点数等关键参数对可靠性性能的影响。通过数值比较和蒙特卡罗仿真验证了该算法的有效性。本文提出的控制策略为提高机械工程的可靠性性能提供了理论指导，具有广阔的应用前景。

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引用次数: 0

Features of different variants for optimal design of vibro-impact nonlinear energy sinks affecting their efficiency and dynamics 振动冲击非线性能量汇优化设计中不同变型的特性对其效率和动力学的影响

IF 3.2 3区工程技术 Q2 MECHANICS

International Journal of Non-Linear Mechanics

Pub Date : 2025-08-13 DOI: 10.1016/j.ijnonlinmec.2025.105220

Petro Lizunov , Olga Pogorelova , Tetyana Postnikova

This paper studies the performance of the vibro-impact nonlinear energy sinks (VI NESs) with different sets of optimized parameters under periodic excitation. Single-sided and double-sided VI NESs with different mass ratios are considered. Two variants of the damper parameter groups are presented, which exhibit sufficiently high but different efficiency for mitigating the primary structure (PS) vibrations. The high efficiency is maintained despite the complex damper dynamics with irregular movements and narrow areas of nonlinearity. The VI NESs with the smaller mass ratios show a special behavior. Some of their optimized parameters take on non-standard low-realistic values, namely, the clearance becomes very large and the damping coefficient becomes too small. The symmetry of the dynamics of a symmetric double-sided VI NES with a small mass ratio is broken. The dynamics becomes complex, with irregular motions and asymmetric impacts on the obstacles.

本文研究了周期激励下不同优化参数组的振动冲击非线性能量汇的性能。考虑了不同质量比的单面和双面VI度。提出了阻尼器参数组的两种变体，它们在抑制主结构振动方面表现出足够高但不同的效率。尽管阻尼器动力学复杂，运动不规则，非线性区域狭窄，但仍能保持高效率。质量比较小的VI表现出特殊的行为。他们的一些优化参数呈现出非标准的低真实感值，即间隙变得非常大，阻尼系数变得太小。破坏了小质量比对称双面VI NES的动力学对称性。动力学变得复杂，运动不规则，对障碍物的影响不对称。

引用次数: 0

Three-dimensional kinematic plastic limit analysis with plastic incompressibility and conic programming 具有塑性不可压缩性和二次规划的三维运动塑性极限分析

IF 3.2 3区工程技术 Q2 MECHANICS

International Journal of Non-Linear Mechanics

Pub Date : 2025-08-11 DOI: 10.1016/j.ijnonlinmec.2025.105215

Trung-Dung Tran , Canh V. Le , Phuc L.H. Ho , Duc-Chinh Pham

This paper presents a novel extension of the kinematic limit analysis framework by incorporating hydrostatic stress effects into the plastic dissipation function, enabling the modeling of pressure-sensitive failure mechanisms. The associated dissipation function is reformulated to relax the plastic incompressibility constraint, resulting in a generalized optimization problem amenable to second-order cone programming (SOCP). To address volumetric locking in low-order elements, the node-based smoothed finite element method (NS-FEM) is employed, enhancing numerical accuracy and convergence. The proposed formulation is validated through several benchmark problems, including structures with stress concentrations and pressure-dominant states. Results demonstrate the method’s ability to capture both global and localized collapse mechanisms, offering a robust and efficient alternative to classical approaches in the analysis of pressure-sensitive materials and porous structures.

本文提出了一种运动极限分析框架的新扩展，将静水应力效应纳入塑性耗散函数，从而实现了压敏破坏机制的建模。通过对相关耗散函数的重新表述，放宽了塑性不可压缩约束，得到了一个适用于二阶锥规划（SOCP）的广义优化问题。为了解决低阶单元的体积锁定问题，采用了基于节点的光滑有限元法（NS-FEM），提高了数值精度和收敛性。提出的公式通过几个基准问题进行了验证，包括应力集中和压力主导状态的结构。结果表明，该方法能够捕获全局和局部坍塌机制，为分析压敏材料和多孔结构的经典方法提供了一种强大而有效的替代方法。

引用次数: 0

Exploring the influence of heat treatment on the progressive unloading-reloading behavior of 3D-printed polylactic acid through experiments and viscoplastic model 通过实验和粘塑性模型，探讨热处理对3d打印聚乳酸的递进卸载-再加载行为的影响

IF 3.2 3区工程技术 Q2 MECHANICS

International Journal of Non-Linear Mechanics

Pub Date : 2025-08-09 DOI: 10.1016/j.ijnonlinmec.2025.105240

Shrushti Maheshwari , Koushik Chatterjee , Sarthak S. Singh

The increased use of 3D-printed PLA components demands post-processing to improve their mechanical characteristics and address limitations. This study examines the impact of temperature and heat treatment on the progressive unloading and reloading response of 3D-printed PLA samples under compression, a topic currently underexplored from experimental and modeling point of view. The samples were heat-treated (HT) at 75 ^°C and 90 ^°C for 120 min. The degree of crystallinity increased from 3 % (for untreated (UT)) to 54 % for HT-90(120) samples. The compressive yield strength improved from 58 MPa (for UT) to 72 MPa in HT-90(120) as the heat-treated-induced crystallinity change reduced chain mobility. The progressive unloading and reloading experiments were conducted at 27 °C, 37 °C, and 47 °C, and to better represent the crystallinity variation, UT, HT-75(120), and HT-90(120) samples were considered. The loading curve showed linear elastic stiffness, followed by nonlinear pre-peak hardening, yielding, strain softening, or strain hardening, whereas the unloading curve showed a nonlinear response, gradually decreasing stiffness as strain recovered. HT-90(120) showed the lowest hysteresis loss ratio across all cycles, indicating the least energy loss due to stable molecular arrangement. A nonlinear microstructure-based viscoplastic constitutive model was developed to predict the viscoplastic deformation behavior of 3D-printed semi-crystalline materials during progressive unloading and reloading. The model, consisting of two parallel molecular networks representing amorphous and crystalline phases, accurately predicted the unloading and reloading responses of UT, HT-75(120), and HT-90(120) under specific temperature ranges.

3d打印PLA组件的使用越来越多，需要后处理以改善其机械特性并解决局限性。本研究考察了温度和热处理对压缩下3d打印PLA样品的渐进卸载和再加载响应的影响，这是目前从实验和建模的角度来看尚未充分探索的主题。样品在75°C和90°C下热处理120分钟。结晶度从3%（未处理的（UT））增加到54 % HT-90（120）样品。HT-90的抗压屈服强度从58 MPa （UT）提高到72 MPa(120)，这是由于热处理引起的结晶度变化降低了链的迁移率。在27°C、37°C和47°C下进行递进卸载和再加载实验，为了更好地反映结晶度变化，我们考虑了UT、HT-75（120）和HT-90（120）样品。加载曲线表现为线性弹性刚度，其次是非线性峰前硬化、屈服、应变软化或应变硬化；卸载曲线表现为非线性响应，随着应变恢复刚度逐渐降低。HT-90（120）在所有周期中迟滞损失率最低，表明由于分子排列稳定，能量损失最小。为了预测3d打印半晶材料在递进卸载和再加载过程中的粘塑性变形行为，建立了基于非线性微观结构的粘塑性本构模型。该模型由代表非晶相和结晶相的两个平行分子网络组成，准确预测了UT、HT-75（120）和HT-90（120）在特定温度范围内的卸载和再加载响应。

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引用次数: 0