Ultrasonics最新文献_第5页

Development of an automatic damage detection methodology using ultrasonic piezoelectric sensors under varying temperature conditions 在变温度条件下使用超声波压电传感器的自动损伤检测方法的发展

IF 4.1 2区物理与天体物理 Q1 ACOUSTICS

Ultrasonics

Pub Date : 2026-01-06 DOI: 10.1016/j.ultras.2025.107947

Trésor Kanyiki

This article presents an experimental study of the effects of temperature variations on ultrasonic waves and proposes a methodology to improve the robustness of damage-detection indicators under such environmental conditions. The investigation is based on laboratory tests carried out in air on specimens instrumented with embedded piezoelectric sensors and subjected to controlled thermal cycles. As a first step, the well-known time-stretching technique is applied to correct propagation delays induced by thermal expansion and the temperature dependence of wave speed. Interestingly, while this method remains effective for moderate excursions, its performance degrades at higher temperatures due to strong waveform distortion. Under such conditions, classical indicators relative velocity variation and correlation coefficient-lose reliability.

To overcome this limitation, we evaluate three processing chains that combine time-stretching with (i) an autoassociative neural network (autoencoder), (ii) principal component analysis (PCA), and (iii) a support vector machine (SVM). The first two approaches extract features that are more resilient to thermal effects and provide better stability when temperature fluctuates. In addition, the squared Euclidean distance between the input and its reconstruction is used as a damage indicator, while extreme value statistics (EVS) are employed to define adaptive alarm thresholds; among the candidate tail models, the Fréchet distribution proves particularly suitable for representing the extremes of the indicator. By contrast, in our protocol, the SVM approach does not yield a significant gain.

Overall, the results show that coupling time-stretching with dimensionality reduction (linear or nonlinear) and EVS-based thresholding markedly improves monitoring reliability, distinguishing healthy from damaged states with an acceptable false-alarm rate under variable environmental conditions.

本文提出了温度变化对超声波影响的实验研究，并提出了一种在这种环境条件下提高损伤检测指标鲁棒性的方法。这项研究是基于在空气中对装有嵌入式压电传感器的标本进行的实验室测试，并进行受控的热循环。作为第一步，我们采用了众所周知的时间拉伸技术来校正由热膨胀引起的传播延迟和波速的温度依赖性。有趣的是，虽然这种方法对中等偏移仍然有效，但由于强烈的波形失真，其性能在高温下会下降。在这种情况下，经典指标相对速度变化和相关系数失去了可靠性。为了克服这一限制，我们评估了三种将时间拉伸与(i)自关联神经网络（autoencoder），（ii）主成分分析（PCA）和（iii）支持向量机（SVM）相结合的处理链。前两种方法提取的特征对热效应更有弹性，并且在温度波动时提供更好的稳定性。采用输入与重建之间的欧式距离的平方作为损伤指标，采用极值统计（EVS）定义自适应报警阈值；在候选的尾部模型中，fr切特分布被证明特别适合表示该指标的极值。相比之下，在我们的协议中，支持向量机方法并没有产生显著的增益。总体而言，结果表明，耦合时间拉伸与降维（线性或非线性）和基于ev的阈值方法显著提高了监测可靠性，在可变环境条件下以可接受的误报率区分健康状态和损坏状态。

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引用次数: 0

Evaluation of early-stage corrosion damage using quasi-static component pulse generated by longitudinal critically refracted (LCR) wave 利用纵向临界折射波产生的准静态分量脉冲评价早期腐蚀损伤

IF 4.1 2区物理与天体物理 Q1 ACOUSTICS

Ultrasonics

Pub Date : 2026-01-06 DOI: 10.1016/j.ultras.2026.107953

Meng Qinghang , Gu Bin , Yuan Weifeng , Deng Mingxi , Ding Xiangyan , Hu Ning , Wang Jishuo

The nonlinear ultrasonic technique is an effective method for characterizing early-stage damage, such as initial corrosion, plastic deformation, and creep. However, the nonlinear response signal induced by micro-damage is typically one or two orders of magnitude weaker than the fundamental wave. This low signal-to-noise ratio is one of the main factors limiting the broader application of nonlinear ultrasonic technology. To address this issue, this study systematically investigates the quasi-static component pulse (QSCP) generated during the propagation of the longitudinal critically refracted (LCR) wave. The feasibility of assessing early corrosion damage in 7075 aluminum alloy was evaluated using the QSCP, a signal feature resulting from the interaction between corrosion-induced microcrack and LCR wave. Both numerical simulation and experimental results demonstrate a positive correlation between the QSCP-based acoustic nonlinearity parameter (ANP) and the extent of corrosion-induced microcrack, which is attributed to the increase in microcrack. Simulation results show that the ANP increases monotonically with the number of microcrack. This trend is experimentally validated, with the ANP showing a significant increase of approximately 54.8% by the fourth stage of corrosion compared to the baseline. These findings confirm the effectiveness and feasibility of the QSCP-based ANP method for detecting early-stage corrosion damage, offering a promising nondestructive approach with high sensitivity for assessing incipient corrosion in critical metallic structures.

非线性超声技术是表征材料初期腐蚀、塑性变形和蠕变等早期损伤的有效方法。然而，微损伤引起的非线性响应信号通常比基波弱一到两个数量级。这种低信噪比是限制非线性超声技术广泛应用的主要因素之一。为了解决这一问题，本研究系统地研究了纵向临界折射（LCR）波传播过程中产生的准静态分量脉冲（QSCP）。利用腐蚀诱发微裂纹与LCR波相互作用产生的信号特征QSCP，对7075铝合金早期腐蚀损伤评估的可行性进行了评价。数值模拟和实验结果均表明，基于qscp的声学非线性参数（ANP）与腐蚀诱发微裂纹的程度呈正相关，这归因于微裂纹的增加。仿真结果表明，ANP随微裂纹数量的增加而单调增加。这一趋势得到了实验验证，与基线相比，在腐蚀的第四阶段，ANP显着增加了约54.8%。这些发现证实了基于qscp的ANP方法检测早期腐蚀损伤的有效性和可行性，为评估关键金属结构的早期腐蚀提供了一种有前途的高灵敏度无损方法。

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引用次数: 0

Full-wave modeling of transcranial ultrasound using volume-surface integral equations and CT-derived heterogeneous skull data 使用体积-表面积分方程和ct衍生的异质颅骨数据的经颅超声全波建模。

IF 4.1 2区物理与天体物理 Q1 ACOUSTICS

Ultrasonics

Pub Date : 2026-01-06 DOI: 10.1016/j.ultras.2026.107954

Alberto Almuna-Morales , Danilo Aballay , Pierre Gélat , Reza Haqshenas , Elwin van ’t Wout

Transcranial ultrasound therapy uses focused acoustic energy to induce therapeutic bioeffects in the brain. Ultrasound must be transmitted through the skull, which is highly attenuating and heterogeneous, causing beam distortion, reducing focal pressure, and shifting the target location. Computational models are frequently used to predict beam aberration, assess cranial heating, and correct the phase of ultrasound transducers. These models often rely on computed tomography (CT) images to build patient-specific geometries and estimate skull acoustic properties. However, the coarse voxel resolution of CT limits accuracy for differential equation solvers at ultrasound frequencies. This paper presents an efficient numerical method based on volume-surface integral equations to model full-wave acoustic propagation through heterogeneous skull bone. We show that our approach effectively simulates transcranial ultrasound, even when using the original CT voxels as the computational mesh, where the 0.5 mm voxel length is relatively coarse compared to the shortest wavelength of 3 mm. The method is validated against a high-resolution boundary element model using an averaged skull representation. Simulations using a CT-based skull model and a bowl transducer reveal significant beam distortion of 7.8 mm attributed to the skull’s heterogeneous acoustical properties.

经颅超声治疗利用集中的声能在大脑中诱导治疗生物效应。超声必须通过颅骨传输，这是高度衰减和非均匀的，引起光束畸变，降低焦点压力，并移动目标位置。计算模型经常用于预测光束像差，评估颅骨加热，并纠正超声换能器的相位。这些模型通常依赖于计算机断层扫描（CT）图像来建立患者特定的几何形状和估计头骨声学特性。然而，CT的粗体素分辨率限制了超声频率下微分方程求解的精度。本文提出了一种基于体面积分方程的模拟全波声波在非均匀颅骨中的传播的有效方法。我们表明，即使使用原始CT体素作为计算网格，我们的方法也能有效地模拟经颅超声，其中0.5 mm体素长度与最短的3 mm波长相比相对粗糙。该方法使用平均颅骨表示对高分辨率边界元素模型进行了验证。使用基于ct的颅骨模型和碗形换能器进行的模拟显示，由于颅骨的非均匀声学特性，显著的光束畸变为7.8 mm。

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引用次数: 0

Defect-parameterized physics-informed neural network for forward and inverse modeling of laser ultrasonic wavefield 缺陷参数化物理信息神经网络用于激光超声波场正反演建模。

IF 4.1 2区物理与天体物理 Q1 ACOUSTICS

Ultrasonics

Pub Date : 2026-01-03 DOI: 10.1016/j.ultras.2026.107952

Liu Yang , Peipei Liu , Kiyoon Yi , Tam Van Huynh , Hanbi Byun , Jeaseung Kim , Hyunsung Hwang , Hoon Sohn

Accurate and efficient non-destructive evaluation (NDE) techniques are essential for ensuring the structural integrity of metallic components, where surface defects, as one of the most common types, can severely compromise fatigue life and mechanical performance. Laser ultrasonics provides a non-contact and high-fidelity approach for inspecting metallic components through wavefield-based analysis. However, reconstructing complete ultrasonic fields and identifying defects from limited measurements remain challenging problems. This study proposes a defect-parameterized physics-informed neural network (DP-PINN) for the forward and inverse modeling of laser ultrasonic wavefield, with the objective of characterizing sub-millimeter surface defects in metallic components. The proposed framework embeds defect-related parameters into the governing elastodynamic equations to reconstruct the full wavefield and estimate the wave velocity field, thereby revealing defect characteristics including location and size. To comprehensively assess the method’s performance, four different defect cases are simulated, incorporating different defect characteristics. Furthermore, six practical scenarios are analyzed based on different levels of prior knowledge about material properties and data sparsity. Results demonstrate that defect characterization and full wavefield reconstruction can be achieved with limited measurement data of 0.42 MB. The proposed method maintains consistent detectability across varying defect cases and yields a mean Intersection over Union (

I o U

) of 0.387, indicating quantitative accuracy.

准确、高效的无损评估（NDE）技术对于确保金属部件的结构完整性至关重要，因为表面缺陷是最常见的缺陷之一，会严重影响疲劳寿命和机械性能。激光超声通过波场分析为金属构件的检测提供了一种非接触、高保真的方法。然而，重建完整的超声场和从有限的测量中识别缺陷仍然是具有挑战性的问题。本研究提出了一种缺陷参数化物理信息神经网络（DP-PINN），用于激光超声波场的正演和逆演建模，目的是表征金属部件的亚毫米级表面缺陷。该框架将缺陷相关参数嵌入到控制弹性动力学方程中，重构整个波场并估计波速场，从而揭示缺陷的位置和大小等特征。为了全面评估该方法的性能，模拟了四种不同的缺陷情况，结合了不同的缺陷特征。此外，基于不同水平的材料属性先验知识和数据稀疏性，对六种实际场景进行了分析。结果表明，该方法可以在0.42 MB的有限测量数据下实现缺陷表征和全波场重建。该方法在不同缺陷情况下保持一致的可检测性，平均IoU为0.387，表明了定量精度。

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引用次数: 0

Full-region internal imaging of metals using multi-mode VF-SAFT and surrogate model-assisted optimization of EMAT 利用多模VF-SAFT和替代模型辅助EMAT优化的金属全区域内部成像。

IF 4.1 2区物理与天体物理 Q1 ACOUSTICS

Ultrasonics

Pub Date : 2026-01-02 DOI: 10.1016/j.ultras.2026.107949

Zhengshi Lu , Zhichao Cai , Riteng Sun , Jianfen Wang , Wenhua Hu , Jing Rao

Oblique-incidence EMAT inspection can cover large areas and reduce blind zones, but traditional shear-vertical EMATs (TSV-EMATs) suffer from low conversion efficiency, weak directivity and severe modal interference. This work proposes an Optimized Shear-Vertical EMAT (OSV-EMAT) that uses a permanent-magnet array and a tailored FPC meander-line coil to reshape the magnetic field and enhance SV-wave excitation, purity and steering. A physics-guided semi-analytical model is built to map design parameters to SV-wave displacement and, together with a Kriging surrogate and an off-the-shelf swarm optimiser, performs multi-parameter optimisation without extensive transient finite-element simulations, achieving a 51× speed-up while retaining the optimal geometry. For imaging, a multi-mode variable-frequency synthetic aperture focusing technique (VF-SAFT) scheme steers the SV beam by frequency modulation, avoiding mechanical repositioning, and is combined with a lightweight GRDB-based fusion network to mitigate blind zones from direct and secondary modes. Experiments on a semi-circular aluminium plate show that the OSV-EMAT yields stronger, purer and more directional SV echoes than a TSV-EMAT and attains defect localisation errors below 1.52%, demonstrating an efficient solution for EMAT-based defect imaging.

斜入射EMAT检测可以覆盖面积大、减少盲区，但传统的剪切垂直EMAT （TSV-EMATs）存在转换效率低、指向性弱、模态干扰严重的问题。本工作提出了一种优化的剪切-垂直EMAT (OSV-EMAT)，它使用永磁体阵列和定制的FPC弯曲线线圈来重塑磁场，增强sv波激励，纯度和转向。建立了一个物理引导的半解析模型，将设计参数映射到sv波位移，并与Kriging代理和现成的群优化器一起，无需大量的瞬态有限元模拟即可执行多参数优化，在保持最佳几何形状的同时实现了51倍的加速。在成像方面，多模变频合成孔径聚焦技术（VF-SAFT）方案通过调频控制SV光束，避免机械重新定位，并与基于轻量级grdb的融合网络相结合，减轻直接模式和二次模式的盲区。在半圆形铝板上的实验表明，OSV-EMAT比TSV-EMAT产生更强、更纯净、更定向的SV回波，缺陷定位误差低于1.52%，证明了基于emat的缺陷成像的有效解决方案。

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引用次数: 0

Flexural-guided-wave mode F(1,1) based inspections for small-bore tubes with bends 带有弯头的小口径管道的弯曲导波模式F（1,1）检测

IF 4.1 2区物理与天体物理 Q1 ACOUSTICS

Ultrasonics

Pub Date : 2026-01-02 DOI: 10.1016/j.ultras.2026.107950

Wu Wenjun, Wu Wentao, Wang Li, Su Yonghang, Zhang Ben

Small-bore tubes, which typically serve as critical industrial components, are challenging to inspect due to their inaccessibility and small dimensions. This paper investigates inspections of small-bore tubes with bends using the flexural guided-wave mode F(1,1). A magnetostrictive patch transducer for F(1,1) excitation is proposed, sharing the same architecture as conventional T(0,1) transducers but driven by opposite alternating currents. To address the challenge arising from the significant curvature of small-bore tubes when exciting pure F(1,1) modes, magnetic field simulations were performed to optimize the transducer’s magnetic field uniformity and directivity. The wave motion of F(1,1) is thoroughly studied. It is found that the F(1,1) mode has two focusing regions separated by 90 degrees in circumstance, one for the circumferential vibration focus and the other for the radial vibration focus. Then, the scattering of the F(1,1) mode with varying circumferential or radial focusing positions as it propagates through the bend is numerically analyzed. It is found that when the F(1,1) mode’s circumferential displacement focus aligns with the outward bend, it converts to the T(0,1) mode with each passage through the bend, with no L(0,1) mode generated, and the wave energy at the outward bend is enhanced. When the F(1,1) mode’s radial displacement focus aligns with the outward bend, it converts to the L(0,1) mode with no T(0,1) mode observed, and the wave energy is further focused at the inward bend. When the F(1,1) mode’s circumferential displacement focus is located 45° from the outward bend, both the T(0,1) and L(0,1) modes are scattered. Experiments were conducted to validate the F(1,1) excitation and the numerical simulation results for F(1,1) bend scattering. Furthermore, F(1,1)-based inspections of bent tubes were conducted to experimentally assess the bend scattering behavior and defect detectability. The weak reflections of the F(1,1) mode from the bend itself do not mask flaw signals, thereby enabling the effective detection of crack-like defects with a 6% cross-sectional area loss. The F(1,1) mode with its circumferential displacement focus aligned with the outward bend is more sensitive to flaws located at the outward bend, whereas the F(1,1) mode with its radial displacement focus aligned with the outward bend is more sensitive to flaws located at the inward bend, in good agreement with the simulation results.

小口径管通常是关键的工业部件，由于其难以接近且尺寸小，因此对其进行检测具有挑战性。本文研究了弯曲导波模式F（1,1）对带有弯头的小口径钢管的检测。提出了一种用于F（1,1）激励的磁致伸缩贴片换能器，与传统的T（0,1）换能器具有相同的结构，但由相反的交流电驱动。为了解决在激发纯F（1,1）模式时小口径管的显著曲率所带来的挑战，进行了磁场模拟以优化换能器的磁场均匀性和指向性。对F（1,1）的波动进行了深入的研究。研究发现，在这种情况下，F（1,1）模态具有两个相距90度的聚焦区，一个是周向振动聚焦区，另一个是径向振动聚焦区。然后，数值分析了F（1,1）模式在不同周向或径向聚焦位置下在弯曲处传播时的散射。研究发现，当F（1,1）模态的周向位移焦点对准外弯道时，每次通过弯道都转换为T（0,1）模态，不产生L（0,1）模态，外弯道处的波能增强。当F（1,1）模态径向位移焦点对准外弯时，转换为L（0,1）模态，未观察到T（0,1）模态，波能进一步集中在内弯处。当F（1,1）模态的周向位移焦点位于距外弯45°处时，T（0,1）和L（0,1）模态均为散射态。通过实验验证了F（1,1）激发和F（1,1）弯曲散射的数值模拟结果。此外，对弯曲管进行了基于F（1,1）的检测，以实验评估弯曲散射行为和缺陷可检测性。弯曲本身的F（1,1）模式的弱反射不会掩盖缺陷信号，从而能够以6%的横截面积损失有效检测裂纹类缺陷。周向位移焦点对准外弯的F（1,1）模态对位于外弯的缺陷更敏感，而径向位移焦点对准外弯的F（1,1）模态对位于内弯的缺陷更敏感，与仿真结果吻合较好。

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引用次数: 0

Effective stress monitoring in structures using sideband peak count-index of nonlinear guided waves 非线性导波边带峰值计数指数在结构应力监测中的应用。

IF 4.1 2区物理与天体物理 Q1 ACOUSTICS

Ultrasonics

Pub Date : 2026-01-02 DOI: 10.1016/j.ultras.2026.107951

Yiwei Liu , Meng Wang , Tribikram Kundu , Shili Chen , Jian Li , Zhoumo Zeng , Yang Liu

Ultrasonic guided waves are widely used for structural health monitoring, while traditional stress detection methods based on weak nonlinear elasticity theory suffer from limited sensitivity. This study presents a numerical investigation using the highly sensitive Sideband Peak Count-index (SPC-I) technique for improved stress assessment in plates. A finite element (FE) model is developed to analyze the transient evolution of higher-order harmonics under various uniaxial stress states. This study explores the influence of both stress magnitude and its orientation relative to the wave propagation direction, establishing a quantitative link to the acoustic nonlinear parameter,

β

. The results demonstrate that SPC-I is a robust indicator, sensitive not only to the stress magnitude but also to its orientation. Notably, the proposed method significantly enhances measurement sensitivity. Experimental validation confirms that SPC-I values exhibit a pronounced change with stress variations, representing a marked improvement over conventional ultrasonic techniques. The findings establish a theoretical framework for ultrasonic stress detection and provide essential technical guidance for structural health monitoring (SHM) applications.

超声导波在结构健康监测中应用广泛，传统的基于弱非线性弹性理论的应力检测方法灵敏度有限。本研究提出了一项数值研究，使用高灵敏度的边带峰值计数指数（SPC-I）技术来改进板中的应力评估。建立了有限元模型，分析了不同单轴应力状态下高次谐波的瞬态演化。本研究探讨了应力大小及其方向对波传播方向的影响，建立了与声学非线性参数β的定量联系。结果表明，SPC-I是一个稳健的指标，不仅对应力大小敏感，而且对应力方向敏感。值得注意的是，该方法显著提高了测量灵敏度。实验验证证实，SPC-I值随应力变化表现出明显的变化，比传统超声技术有明显的改进。研究结果为超声应力检测建立了理论框架，为结构健康监测提供了必要的技术指导。

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引用次数: 0

IF 4.1 2区物理与天体物理 Q1 ACOUSTICS

Ultrasonics

Pub Date : 2026-01-01

引用次数: 0

IF 4.1 2区物理与天体物理 Q1 ACOUSTICS

Ultrasonics

Pub Date : 2026-01-01

引用次数: 0

IF 4.1 2区物理与天体物理 Q1 ACOUSTICS

Ultrasonics

Pub Date : 2026-01-01

引用次数: 0