Mechanics of Materials最新文献_第9页

Achieving geometric accuracy in FFT-based micromechanical models using conformal grid 利用保形网格实现基于fft的微力学模型的几何精度

IF 4.1 3区材料科学 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Mechanics of Materials

Pub Date : 2025-10-01 DOI: 10.1016/j.mechmat.2025.105512

Miroslav Zecevic, Ricardo A. Lebensohn, Laurent Capolungo

Owing to its efficiency, simplicity and robustness, the FFT-based method has become the standard for computation of mechanical fields in a heterogeneous periodic unit cell. One of the main disadvantages of the FFT-based method is the inaccurate representation of the initial microstructure on a regular grid of voxels, which can be alleviated through the use of distorted initial grids. In this paper, a method for generation of distorted initial grids conforming to the microstructural features (e.g. straight/curved boundaries) is proposed. The method determines the positions of the grid nodes in the initial configuration by solving a system of springs connecting the nodes. Microstructures consisting of layers, Voronoi tessellation and circular/spherical inclusions are considered, and mechanical fields simulated using the FFT-based method. It is found that distorted initial grids, conforming to the microstructural features, lead to more accurate mechanical fields in comparison to the corresponding non-distorted initial grid solution. The effect of initial grid distortion on the convergence of the FFT-based method is analyzed and discussed.

基于fft的方法由于其高效、简单和鲁棒性，已成为计算非均匀周期单元胞中力学场的标准方法。基于fft的方法的主要缺点之一是初始微观结构在规则体素网格上的不准确表示，可以通过使用扭曲的初始网格来缓解这一问题。本文提出了一种生成符合微观结构特征（如直/弯边界）的畸变初始网格的方法。该方法通过求解连接节点的弹簧系统来确定网格节点在初始构型中的位置。考虑了由层、Voronoi镶嵌和圆形/球形夹杂组成的微观结构，并使用基于fft的方法模拟了力学场。结果表明，与非畸变初始网格解相比，畸变初始网格解得到的力学场更为精确，且符合微观结构特征。分析和讨论了初始网格畸变对基于fft的方法收敛性的影响。

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引用次数: 0

A viscoplasticity model with an invariant-based non-Newtonian flow rule for unidirectional thermoplastic composites 单向热塑复合材料粘塑性模型与基于不变量的非牛顿流动规则

IF 4.1 3区材料科学 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Mechanics of Materials

Pub Date : 2025-09-30 DOI: 10.1016/j.mechmat.2025.105507

P. Hofman, D. Kovačević, F.P. van der Meer, L.J. Sluys

A three-dimensional mesoscopic viscoplasticity model for simulating rate-dependent plasticity and creep in unidirectional thermoplastic composites is presented. The constitutive model is a transversely isotropic extension of an isotropic finite strain viscoplasticity model for neat polymers. Rate-dependent plasticity and creep are described by a non-Newtonian flow rule where the viscosity of the material depends on an equivalent stress measure through an Eyring-type relation. In the present formulation, transverse isotropy is incorporated by defining the equivalent stress measure and flow rule as functions of transversely isotropic stress invariants. In addition, the Eyring-type viscosity function is extended with anisotropic pressure dependence. As a result of the formulation, plastic flow in fiber direction is effectively excluded and pressure dependence of the polymer matrix is accounted for. The re-orientation of the transversely isotropic plane during plastic deformations is incorporated in the constitutive equations, allowing for an accurate large deformation response. The formulation is fully implicit and a consistent linearization of the algorithmic constitutive equations is performed to derive the consistent tangent modulus. The performance of the mesoscopic constitutive model is assessed through a comparison with a micromechanical model for carbon/PEEK, with the original isotropic viscoplastic version for the polymer matrix and with hyperelastic fibers. The micromodel is first used to determine the material parameters of the mesoscale model with a few stress–strain curves. It is demonstrated that the mesoscale model gives a similar response to the micromodel under various loading conditions. Finally, the mesoscale model is validated against off-axis experiments on unidirectional thermoplastic composite plies.

提出了一种用于模拟单向热塑性复合材料速率相关塑性和蠕变的三维细观粘塑性模型。本构模型是纯聚合物的各向同性有限应变粘塑性模型的横向各向同性扩展。速率相关的塑性和蠕变由非牛顿流动规则描述，其中材料的粘度取决于等效应力测量，通过eyring型关系。在本公式中，通过将等效应力测量和流动规律定义为横向各向同性应力不变量的函数，纳入了横向各向同性。此外，对eyring型黏度函数进行了扩展，使其具有各向异性压力依赖性。由于该配方，有效地排除了纤维方向的塑性流动，并考虑了聚合物基体的压力依赖性。在塑性变形过程中，横向各向同性平面的重新定向被纳入本构方程，允许精确的大变形响应。该公式是完全隐式的，并对算法本构方程进行了一致线性化，以导出一致切线模量。通过与碳/PEEK的微观力学模型、聚合物基体的原始各向同性粘塑性模型和超弹性纤维的微观力学模型的比较，评估了介观本构模型的性能。首先采用微观模型确定具有少量应力-应变曲线的中尺度模型的材料参数。结果表明，在不同的加载条件下，中尺度模型与微观模型具有相似的响应。最后，通过对单向热塑性复合材料层的离轴实验对中尺度模型进行了验证。

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引用次数: 0

Investigating the interfacial behavior of van der Waals heterostructures with nano-inclusions: Molecular dynamics simulation and theoretical analysis 范德华异质结构与纳米内含物的界面行为研究：分子动力学模拟与理论分析

IF 4.1 3区材料科学 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Mechanics of Materials

Pub Date : 2025-09-30 DOI: 10.1016/j.mechmat.2025.105514

Liqun Lou , Peijian Chen , Hao Liu , Guangjian Peng , Juan Peng

Interfacial properties of van der Waals (vdW) heterostructures are of crucial significance for precision instruments, microelectronics, mechanical and electrical engineering and so on. However, the lack of study on interfacial response of vdW heterostructures with nanoparticle greatly hinders the reliability and stability of various novel devices. Herein, we perform theoretical analysis and molecular dynamics simulation to explore the configuration and cohesive energy of vdW heterostructures with nano-inclusions. It is found that our proposed model functions well to predict morphologies of vdW heterostructure at the equilibrium state. The parameters dominating the formed morphology of vdW heterostructures are clarified. What is more, the interfacial behavior of vdW heterostructures can be modified by tuning the size, number, aggregation and interfacial interactions of nano-inclusions. The results should be helpful for not only improving the knowledge of surface/interface mechanics, but also guiding applications of two-dimensional materials and the corresponding vdW heterostructures.

范德华异质结构的界面特性在精密仪器、微电子、机电工程等领域具有重要意义。然而，缺乏对vdW异质结构与纳米颗粒界面响应的研究，极大地阻碍了各种新型器件的可靠性和稳定性。本文通过理论分析和分子动力学模拟来探讨含有纳米包体的vdW异质结构的构型和内聚能。结果表明，该模型能较好地预测vdW异质结构在平衡态的形貌。阐明了决定vdW异质结构形成形态的参数。此外，可以通过调节纳米夹杂物的大小、数量、聚集和界面相互作用来改变vdW异质结构的界面行为。研究结果不仅有助于提高表面/界面力学知识，而且对二维材料和相应的vdW异质结构的应用具有指导意义。

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引用次数: 0

Variationally consistent microstructure evolution and microsphere-based reconvexification for damage with application to arterial tissues 动脉组织损伤的显微结构演化与微球再凸化

IF 4.1 3区材料科学 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Mechanics of Materials

Pub Date : 2025-09-29 DOI: 10.1016/j.mechmat.2025.105495

Jan Melchior, Maximilian Köhler, Daniel Balzani

Modeling the softening of arterial tissue, as it can be observed in terms of strain softening preceding atherosclerotic plaque rupture or in terms of stress-softening during balloon angioplasty, places special demands on the material formulations employed. In the context of finite-element discretized boundary value problems, the softening of the material is typically associated with a non-convex strain energy, which leads to an ill-posed behavior, i.e., mesh-dependency. In this work, we discuss the applicability of a material model for strain-softening that is based on the repeated construction of the convex envelope of an initially non-convex strain energy. The model possesses an evolving property that is exploited for the description of material softening. We propose an accurate and efficient convexification method, which is based on the reformulation of the convexity requirement in terms of a new optimization problem. Furthermore, we adopt the formulation to model softening in arterial tissue by combining a microsphere approach with a new orientation distribution function representing the dispersion of collagen fibers and show its capability to represent experimental data. Finally, we provide the derivation of a variationally sound approach to damage microstructure evolution and analyze some unique aspects significantly limiting the applicability to strain-softening.

在动脉粥样硬化斑块破裂前的应变软化或球囊血管成形术期间的应力软化方面，可以观察到动脉组织的软化建模，这对所采用的材料配方提出了特殊要求。在有限元离散边值问题的背景下，材料的软化通常与非凸应变能相关，这导致了不适定行为，即网格依赖。在这项工作中，我们讨论了基于初始非凸应变能的凸包络的重复构造的应变软化材料模型的适用性。该模型具有可用于描述材料软化的演化特性。针对一个新的优化问题，提出了一种精确高效的凸化方法，该方法基于对凸性要求的重新表述。此外，我们将微球方法与代表胶原纤维分散的新取向分布函数相结合，采用该配方来模拟动脉组织中的软化，并展示其表示实验数据的能力。最后，我们推导了一种损伤微观结构演变的变响方法，并分析了一些显著限制应变软化适用性的独特方面。

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引用次数: 0

Enhanced high-temperature creep resistance in gradient nanograined Fe-Zr alloy via gradient Zr segregation stabilizing grain boundary 通过梯度Zr偏析稳定晶界提高梯度纳米晶Fe-Zr合金的高温抗蠕变性能

IF 4.1 3区材料科学 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Mechanics of Materials

Pub Date : 2025-09-27 DOI: 10.1016/j.mechmat.2025.105513

Daqian Xu , Zhifeng Huang , Hao Li , Vladyslav Turlo , Like Xu , Qiang Shen , Fei Chen

Fine and ultrafine grains in the gradient nanograined (GNG) structure exhibit low creep resistance. As these grains grow, they will further influence the hetero-deformation behavior when interacting with coarse grains under tensile loading. Solute segregation could be effective for stabilizing nanograins, but the distribution of solute atoms and its influence on the structure-performance relationship in the GNG structure remain unclear. Here, the Zr solute segregation gradient is found energetically favorable in the Fe-Zr GNG alloy based on molecular dynamics simulations, where the solute concentration at GBs shows a gradient distribution across the GNG structure. This dual heterogeneity contributes to improved creep resistance while also retaining the hetero-deformation induced strengthening nature of the GNG structure. A pseudo-composite structure is then demonstrated from the dual heterogeneity structure design: the finer grain region with higher segregation concentration, which acts as the thermodynamical stabilizer to enhance creep resistance; and the coarser grain region with smaller segregation concentration, which acts as plastic deformer to provide necessary hetero-deformation accommodation ability. Our work introduces segregation-induced concentration gradient into traditional heterogeneous materials and presents a new route for improving the creep resistance and tensile properties of heterostructure materials.

梯度纳米晶（GNG）结构中的细晶粒和超细晶粒表现出较低的抗蠕变性能。随着这些晶粒的长大，它们将进一步影响拉伸载荷下与粗晶粒相互作用时的异质变形行为。溶质偏析可以有效地稳定纳米颗粒，但在GNG结构中，溶质原子的分布及其对结构-性能关系的影响尚不清楚。基于分子动力学模拟，发现Fe-Zr GNG合金中Zr溶质偏析梯度在能量上是有利的，其中GBs处的溶质浓度在整个GNG结构中呈现梯度分布。这种双重非均质性有助于提高抗蠕变性能，同时也保留了GNG结构的非均质变形强化性质。通过双非均质结构设计，得到了伪复合结构：具有较高偏析浓度的细晶区作为热稳定剂，增强了材料的抗蠕变性能；晶粒较粗，偏析浓度较小，起到塑性变形的作用，提供了必要的异质变形调节能力。本研究将偏析诱导浓度梯度引入到传统异质材料中，为提高异质结构材料的抗蠕变性能和拉伸性能提供了一条新的途径。

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引用次数: 0

Mechanical structure–property relations in flexible silica-aerogels 柔性硅气凝胶的力学结构-性能关系

IF 4.1 3区材料科学 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Mechanics of Materials

Pub Date : 2025-09-27 DOI: 10.1016/j.mechmat.2025.105510

Max Zinke , Barbara Milow , Gunnar Seide , Ameya Rege

Flexible aerogels exhibit unique mechanical properties, yet standardisation in their testing methodologies remains limited. This study investigates the tensile and compressive behaviour of flexible aerogels through experimental and computational approaches. Cyclic compression tests are performed to assess damage evolution, while digital image correlation is utilised to measure lateral strain and evaluate the influence of different spraying patterns on strain measurement accuracy. Challenges associated with tensile and compressive testing are critically analysed, highlighting inconsistencies in current practices. Finite element modelling is employed to examine the role of friction in inducing the barrelling effect under compressive loads. The findings underscore the necessity for standardised mechanical testing protocols for flexible aerogels and provide insights into their deformation behaviour under various loading conditions.

柔性气凝胶具有独特的机械性能，但其测试方法的标准化仍然有限。本研究通过实验和计算方法研究了柔性气凝胶的拉伸和压缩行为。通过循环压缩试验评估损伤演化，利用数字图像相关技术测量侧向应变，评估不同喷射方式对应变测量精度的影响。与拉伸和压缩测试相关的挑战进行了批判性分析，突出了当前实践中的不一致之处。采用有限元模型研究了在压缩载荷作用下摩擦对桶管效应的影响。研究结果强调了对柔性气凝胶进行标准化力学测试的必要性，并为其在各种加载条件下的变形行为提供了见解。

引用次数: 0

Numerical modelling of the dynamic pull-out of steel fibers from cementitious materials 胶凝材料中钢纤维动态拉拔的数值模拟

IF 4.1 3区材料科学 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Mechanics of Materials

Pub Date : 2025-09-25 DOI: 10.1016/j.mechmat.2025.105511

Bibiana Luccioni , Paula Argañaraz , Facundo Isla

Since fiber pull-out is the main reason for the toughness of fiber-reinforced cementitious composites, it is important to properly simulate this mechanism in dynamic models for this type of materials. Available experimental results show that the pull-out response of steel fibers embedded in concrete matrices exhibits sensitivity to the loading rate. This paper presents a model for the dynamic pull-out of steel fibers from cementitious composites. The model takes into account inertia effects and rate effects that influence the forces at the fiber-matrix interface, matrix micro cracking, mechanical anchorage and snubbing effects. The tangential stresses at the interface are calibrated based on experimental results obtained from pull-out tests of straight fibers performed at different loading rates, from quasi-static loading to impact loading, for different types of concrete matrix, including ultrahigh performance concrete (UHPC). The paper is complemented by the simulation of the pull-out of hooked end fibers at different loading rates and inclinations. The comparison with experimental results shows that the developed pull-out model is able to simulate the dynamic pull-out of steel fibers with different geometries and orientations from different types of concrete matrices. The inertia effects are negligible compared to the contribution of the other mechanisms to the pull-out response and to the effects due to the strain rate dependence of the fiber-matrix interface parameters.

由于纤维拔出是纤维增强胶凝复合材料韧性的主要原因，因此在这类材料的动力学模型中正确地模拟这一机制是很重要的。已有的试验结果表明，嵌入混凝土基体中的钢纤维的拉拔响应对加载速率具有敏感性。本文建立了胶凝复合材料中钢纤维的动态拉拔模型。该模型考虑了影响纤维-基体界面受力的惯性效应和速率效应、基体微裂纹效应、机械锚固效应和缓蚀效应。根据不同类型的混凝土基体（包括超高性能混凝土（UHPC））在不同加载速率（从准静态加载到冲击加载）下进行的直纤维拉拔试验结果，对界面处的切向应力进行了校准。本文还对不同加载速率和倾角下钩端纤维的抽拔进行了模拟。与试验结果的对比表明，所建立的拉拔模型能够模拟不同几何形状和方向的钢纤维从不同类型的混凝土基体中动态拉拔的过程。与其他机制对拔出响应的贡献以及纤维-基体界面参数应变速率依赖性的影响相比，惯性效应可以忽略不计。

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引用次数: 0

Anisotropic plasticity and damage of additively manufactured 316L stainless steel by multiscale approach 多尺度增材制造316L不锈钢的各向异性塑性与损伤

IF 4.1 3区材料科学 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Mechanics of Materials

Pub Date : 2025-09-24 DOI: 10.1016/j.mechmat.2025.105509

K. Siriraksophon , N. Vajragupta , V. Uthaisangsuk

Stainless steel 316L produced by laser powder bed fusion (L-PBF) technique exhibits distinctly patterned microstructures due to directional rapid cooling of successive layers. Thus, its tensile properties are highly anisotropic depending on applied build strategies that often led to inferior performance compared to conventional 316L steel. In this work, a multiscale modeling approach was proposed for more precisely describing effects of complex printed microstructure characteristics on local and overall deformation behaviors of the steel. Micro-scale models incorporated grain morphologies and crystallographic textures developed in different melt pools. Hereby, the strain gradient crystal plasticity (CP) model was used to thoroughly reveal anisotropic stress-strain responses which were primarily driven by crystallographic features. Subsequently, a meso-scale model was employed to elucidate the heterogeneous deformation occurring at the melt pool boundaries, particularly in relation to the specified scanning patterns. Homogenized stress-strain properties of each meso-scale region were obtained from the micro-scale models in conjunction with the Hill48 yield criterion. Furthermore, the Hosford-Coulomb ductile damage model was defined on the meso-scale for representing crack initiations at crucial sites of the melt pools. The model showed that the grain configurations of 45°/0°/45° and −90°/0°/90° in melt pools strongly governed the anisotropic strain hardening behavior of printed samples. Local stress incompatibilities induced by grain and melt pool arrangements according to the defined scanning strategies resulted in different strain localizations and following damages. The approach can further serve as a framework for 3D printed material designs requiring more accurate microstructure-properties relationships.

采用激光粉末床熔合（L-PBF）技术生产的316L不锈钢由于连续层的定向快速冷却而呈现出明显的图案显微组织。因此，它的拉伸性能是高度各向异性的，这取决于应用的构建策略，这往往导致性能低于传统的316L钢。在这项工作中，提出了一种多尺度建模方法，以更精确地描述复杂印刷微观结构特征对钢的局部和整体变形行为的影响。微观尺度模型结合了不同熔池中形成的晶粒形态和晶体结构。因此，采用应变梯度晶体塑性（CP）模型来全面揭示主要由晶体特征驱动的各向异性应力-应变响应。随后，采用一个中尺度模型来解释在熔池边界发生的非均匀变形，特别是与指定扫描模式有关。结合Hill48屈服准则，利用微尺度模型获得了各中尺度区域的均匀化应力-应变特性。此外，在细观尺度上定义了霍斯福德-库仑韧性损伤模型，以表示熔池关键部位的裂纹萌生。模型表明，熔池中45°/0°/45°和- 90°/0°/90°的晶粒组态对打印样品的各向异性应变硬化行为有很强的控制作用。根据确定的扫描策略，晶粒和熔池排列引起的局部应力不相容导致不同的应变局部化和后续损伤。该方法可以进一步作为3D打印材料设计的框架，需要更精确的微观结构-性能关系。

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引用次数: 0

Statistics of maximum stress for elastic wave propagation in a random porous solid 弹性波在随机多孔固体中传播的最大应力统计

IF 4.1 3区材料科学 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Mechanics of Materials

Pub Date : 2025-09-23 DOI: 10.1016/j.mechmat.2025.105508

Shiwen Feng , Q.M. Li

The stochastic characteristics of elastic wave scattering in random porous solids lead to the complexity and uncertainty for the determination of local maximum stress. There are limited studies to predict and estimate the maximum stress in such medium mainly due to the lack of efficient and accurate modeling tools. In order to address this issue, this work presents a new approach to quantify the statistics of maximum stress induced by multiple wave scattering effects in such medium. By combining the high-fidelity finite element method with Monte Carlo simulation, this work provides a comprehensive framework for evaluating the mean, standard deviation and probability distribution of maximum stress in random porous solids. It is demonstrated that the mean and standard deviation of maximum stress depend highly on the wave frequency and the correlations among cavities. The probability density function of maximum stress is analytically formulated by Burr Ⅻ distribution where the wave frequency and the correlation among cavities are taken into account jointly. The related parameters involved in the statistical distribution are estimated by maximum likelihood method and the Kolmogorov-Smirnov test is adopted to examine the goodness of fitting distribution. The heavy-tailed behavior observed in the statistical distribution is elaborated by linking to the interaction effects of waves with random microstructures, which is crucial for the dynamic failure assessment of porous solids. Finally, the dynamic stress concentration associated with maximum stress in random porous solid is investigated, which potentially relates to the scatterer resonance effects. This work facilitates the understanding of wave-induced dynamic stress in heterogeneous media, providing a statistical approach for dynamic failure assessment in random porous solids.

随机多孔固体中弹性波散射的随机特性导致了局部最大应力计算的复杂性和不确定性。由于缺乏高效、准确的模拟工具，对此类介质中最大应力的预测和估计研究有限。为了解决这一问题，本文提出了一种新的方法来量化这种介质中由多重波散射效应引起的最大应力的统计。通过将高保真有限元法与蒙特卡罗模拟相结合，为随机多孔固体中最大应力的均值、标准差和概率分布提供了一个综合的评估框架。结果表明，最大应力的平均值和标准差在很大程度上取决于波的频率和空腔之间的相关性。最大应力的概率密度函数由BurrⅫ分布解析表示，同时考虑了波频和空腔间的相关性。采用极大似然法对统计分布中涉及的相关参数进行估计，并采用Kolmogorov-Smirnov检验检验拟合分布的优度。在统计分布中观察到的重尾行为通过将波与随机微观结构的相互作用效应联系起来加以阐述，这对于多孔固体的动态破坏评估至关重要。最后，研究了随机多孔固体中与最大应力相关的动应力集中，这可能与散射共振效应有关。这项工作有助于理解非均质介质中波动引起的动应力，为随机多孔固体的动态破坏评估提供了一种统计方法。

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引用次数: 0

Inversion of the thermomechanical response in nitinol under cyclic loading: an analytical interpretation based on the thermoelastic effect theory 循环载荷下镍钛诺热力学响应的反演：基于热弹性效应理论的解析解释

IF 4.1 3区材料科学 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Mechanics of Materials

Pub Date : 2025-09-22 DOI: 10.1016/j.mechmat.2025.105506

V. Pinto , S. Di Leonardo , G. Pitarresi , G. Burriesci

The superelastic behaviour of nitinol is crucial for the design of collapsible and self-expanding cardiovascular implants. Once these are expanded into the host anatomy, the material is predominantly in the austenitic configuration in the majority of the structure, and the cyclic loads acting on the devices are primarily due to small blood pressure variations occurring during the cardiac cycle. Nevertheless, only very few studies have explored the temperature evolution during small cyclic loading of nitinol in a stable austenitic state, reporting an unusual response, where the thermoelastic signal is in phase with the sinusoidal loading wave, rendering the common fundamental law of the thermoelastic effect inapplicable. In this study, infrared thermography (IRT) was employed to investigate the thermomechanical behaviour of an austenitic nitinol specimen under cyclic sinusoidal loading, with increasing amplitude and average strain values. An inversion of the thermomechanical response of nitinol was observed experimentally and explained analytically adopting the higher-order thermoelastic theory. The understanding of the austenitic temperature modulation with the local level of stress allowed to define an IRT approach suitable to quantify the stress levels, knowing the material thermal response and the ratio between mean and amplitude of the applied load.

镍钛诺的超弹性特性对可折叠和自膨胀心血管植入物的设计至关重要。一旦这些扩展到宿主解剖结构中，材料在大多数结构中主要处于奥氏体结构，并且作用在设备上的循环负荷主要是由于心脏周期期间发生的小血压变化。然而，只有很少的研究探讨了镍钛诺在稳定奥氏体状态下的小循环加载过程中的温度演变，报道了一个不寻常的响应，其中热弹性信号与正弦加载波相一致，使得热弹性效应的一般基本定律不适用。在本研究中，红外热成像（IRT）研究了奥氏体镍钛诺试样在循环正弦载荷下的热力学行为，随着振幅和平均应变值的增加。对镍钛诺的热力学响应进行了实验观测，并采用高阶热弹性理论对其进行了解析解释。对奥氏体温度调制与局部应力水平的理解允许定义适合于量化应力水平的IRT方法，了解材料热响应以及施加载荷的平均值和振幅之间的比率。

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引用次数: 0