Experimental Mechanics最新文献

On the Cover: Strain Mapping in the Vicinity of Cracks Using a Conical Slit Setup for Angular Dispersive Synchrotron X-Ray Diffraction 封面：用角色散同步加速器x射线衍射的锥形狭缝装置在裂纹附近的应变映射

IF 2.9 3区工程技术 Q2 MATERIALS SCIENCE, CHARACTERIZATION & TESTING

Experimental Mechanics

Pub Date : 2026-09-11 DOI: 10.1007/s11340-026-01370-7

引用次数: 0

On the Cover: Core Collapse Instability of Spirally Wound Jelly-Roll Lithium-Ion Batteries 封面：螺旋缠绕果冻卷锂离子电池的堆芯崩塌不稳定性

IF 2.9 3区工程技术 Q2 MATERIALS SCIENCE, CHARACTERIZATION & TESTING

Experimental Mechanics

Pub Date : 2026-08-06 DOI: 10.1007/s11340-026-01363-6

引用次数: 0

Editorial: Recent Progress in Chemomechanics 社论：化学力学的最新进展

IF 2.9 3区工程技术 Q2 MATERIALS SCIENCE, CHARACTERIZATION & TESTING

Experimental Mechanics

Pub Date : 2026-07-14 DOI: 10.1007/s11340-026-01345-8

K. Zhao, E. Martínez-Pañeda

引用次数: 0

High-Sensitivity Hydrogen Gas Permeation: System Development, Sample Preparation, and Influence of Testing Variables 高灵敏度氢气渗透：系统开发，样品制备和测试变量的影响

IF 2.9 3区工程技术 Q2 MATERIALS SCIENCE, CHARACTERIZATION & TESTING

Experimental Mechanics

Pub Date : 2026-06-30 DOI: 10.1007/s11340-026-01339-6

R. Li, A. Zafra, Z. D. Harris, E. Martínez-Pañeda

Background

There is a need to develop quantitative, high-resolution hydrogen gas (H(_2)) permeation techniques to provide a better understanding of hydrogen-material interactions, from hydrogen uptake and diffusion to embrittlement.

Objective

This study aims to develop and validate a high-sensitivity H(_2) permeation system, which is then leveraged to systematically quantify the influence of surface condition and key testing variables (surface oxides, residual gas impurities, pressure, and temperature) on hydrogen permeation.

Methods

A gas permeation system capable of operating at pressures up to 50 bar and temperatures up to 250 (^circ )C was developed, incorporating high-sensitivity mass spectrometric detection and controlled surface preparation protocols. Permeation transients were analysed in a model material (annealed pure Fe) to determine hydrogen diffusivity and permeability under systematically varied surface states, oxygen contents, pressures and temperatures.

Results

Surface oxides are shown to play a dominant role in controlling hydrogen permeation at room temperature. The presence of oxide layers can severely hinder or completely suppress hydrogen uptake, with measurable permeation requiring oxide removal via pickling and Pd coating on both surfaces, or activation through hydrogen-assisted reduction at elevated temperature. Residual oxygen present prior to hydrogen exposure further reduces permeability by modifying surface boundary conditions, indicating strongly surface-controlled kinetics. Under optimised surface conditions, hydrogen transport follows bulk diffusion-controlled behaviour, with steady-state flux obeying Sieverts’ law at 25 (^circ )C (1-5 bar) and diffusivity and permeability exhibiting Arrhenius behaviour between 25 and 150 (^circ )C at 5 bar, indicating bulk diffusion-controlled transport.

Conclusions

The developed high-sensitivity permeation system resolves hydrogen fluxes as low as 1.98 (times ) 10(^{-9}) mol/(m(^2) (cdot )s) and provides a robust platform for investigating surface, mechanical and environmental effects on hydrogen permeation under realistic service conditions.

有必要开发定量的、高分辨率的氢气（H (_2)）渗透技术，以更好地了解氢与材料的相互作用，从氢的吸收、扩散到脆化。目的建立并验证高灵敏度H (_2)渗透系统，系统量化表面条件和关键测试变量（表面氧化物、残余气体杂质、压力和温度）对氢气渗透的影响。方法采用高灵敏度质谱检测和可控表面制备工艺，开发了一种压力可达50 bar、温度可达250 (^circ ) C的气体渗透系统。分析了模型材料（退火纯铁）在不同表面状态、氧含量、压力和温度下的渗透瞬态，以确定氢的扩散率和渗透率。结果室温下，表面氧化物对氢的渗透起主导作用。氧化层的存在会严重阻碍或完全抑制氢的吸收，需要通过酸洗和在两个表面涂上Pd来去除氧化物，或者通过高温下的氢辅助还原来激活。在氢暴露之前存在的残余氧通过改变表面边界条件进一步降低了渗透率，表明强烈的表面控制动力学。在优化的表面条件下，氢输运遵循体扩散控制行为，在25 (^circ )℃（1-5 bar）下，稳态通量符合Sieverts定律，在25 - 150 (^circ )℃（5 bar）之间，扩散率和渗透率表现出Arrhenius行为，表明体扩散控制输运。结论所开发的高灵敏度渗透系统可分辨低至1.98 (times ) 10 (^{-9}) mol/(m (^2)(cdot ) s)的氢通量，为研究实际服役条件下表面、力学和环境对氢渗透的影响提供了可靠的平台。

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引用次数: 0

Chemomechanical Degradation at Inorganic Solid Electrolyte-Lithium Metal Interfaces 无机固体电解质-锂金属界面的化学力学降解

IF 2.9 3区工程技术 Q2 MATERIALS SCIENCE, CHARACTERIZATION & TESTING

Experimental Mechanics

Pub Date : 2026-06-30 DOI: 10.1007/s11340-026-01342-x

M. Lu, Z. Liu, H. Chen, S. Xia

Background

Chemomechanically driven degradation at solid electrolyte-lithium metal interfaces is a critical barrier to the reliability of solid-state lithium-ion batteries. Although interphase formation at these interfaces is well recognized, how reaction-induced deformation and stress evolution depend on electrolyte microstructure remains poorly understood.

Objective

This study aims to directly quantify the coupled evolution of interphase growth, deformation, and stress, and to determine how electrolyte microstructure influences stress localization and fracture during interphase formation.

Methods

An integrated in situ experimental platform combining optical imaging, mechanical load measurement, and electrochemical impedance spectroscopy was developed to characterize interphase growth and stress evolution in a model sulfide electrolyte (Li₁₀SnP₂S₁₂). Reaction-induced volumetric strain and interphase roughness were quantified from operando imaging, and finite element simulations incorporating reaction-induced eigenstrain were performed to resolve stress localization mechanisms.

Results

Interphase growth kinetics were comparable across microstructures; however, dense electrolyte pellets exhibited larger reaction-induced volumetric strains, pronounced interphase roughness, sustained pressure buildup, and tensile microcracking despite globally compressive loading. Simulations revealed that rough interphase morphologies generate substantial localized tensile stress through geometric stress amplification, explaining the observed cracking behavior.

Conclusions

These results demonstrate that electrolyte microstructure critically governs how interphase evolution translates into stress localization and fracture, highlighting microstructural control as a key strategy for mitigating chemomechanical degradation in solid-state lithium-ion batteries.

固体电解质-锂金属界面化学力学驱动的退化是固态锂离子电池可靠性的关键障碍。虽然这些界面的界面相形成已经得到了很好的认识，但反应引起的变形和应力演变如何依赖于电解质微观结构仍然知之甚少。目的直接量化间相生长、变形和应力的耦合演化，确定电解质微观结构对间相形成过程中应力局部化和断裂的影响。方法建立了一个集光学成像、机械载荷测量和电化学阻抗谱为一体的集成原位实验平台，以表征模型硫化物电解质（Li₁₀SnP₂S₁₂）的界面生长和应力演化。利用operando成像对反应诱导的体积应变和界面粗糙度进行了量化，并进行了包含反应诱导的特征应变的有限元模拟，以解决应力局部化机制。结果不同微观结构间相生长动力学具有可比性；然而，致密的电解质颗粒表现出更大的反应诱导的体积应变、明显的相间粗糙度、持续的压力积聚和拉伸微裂纹，尽管存在全局压缩载荷。模拟结果表明，粗糙的相间形态通过几何应力放大产生了大量的局部拉应力，解释了观察到的开裂行为。这些结果表明，电解质微观结构对相演化转化为应力局部化和断裂起着关键作用，强调微观结构控制是缓解固态锂离子电池化学力学退化的关键策略。

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引用次数: 0

Strain Mapping in the Vicinity of Cracks Using a Conical Slit Setup for Angular Dispersive Synchrotron X-Ray Diffraction 角色散同步辐射x射线衍射用锥形狭缝装置在裂纹附近的应变映射

IF 2.9 3区工程技术 Q2 MATERIALS SCIENCE, CHARACTERIZATION & TESTING

Experimental Mechanics

Pub Date : 2026-06-18 DOI: 10.1007/s11340-026-01336-9

F. Loebich, N. Möller, J. Richter, T. Wegener, D. Canelo-Yubero, E. Maawad, N. Schell, J. Gibmeier, T. Niendorf

Background

Laser-based powder bed fusion (PBF-LB/M) is a manufacturing technique that enables tailoring of the properties of components towards the application, provided the process parameters are adjusted. However, the process induces residual strain and stresses, influencing, i.e., the fatigue properties. To analyze the residual strain distributions in the vicinity of fatigue cracks in the bulk of specimens a high lateral resolution is necessary, which limits the possible analysis methods to high-energy synchrotron X-ray diffraction.

Objective

The objective is to propose a viable strategy to determine the (lattice) strain distributions in the vicinity of fatigue cracks in AISI 316L compact-tension specimens manufactured via PBF-LB/M.

Methods

An angular dispersive high-energy synchrotron X-ray diffraction setup with conical slits is used, to restrict the gauge volume to the center of the specimens. Complementarily, the residual stress distribution near the surface is investigated using the incremental hole-drilling method.

Results

Along the build direction a compressive residual strain distribution of higher magnitude is found, which is significantly reduced in the vicinity of the crack. Depending on whether the crack opening direction is aligned with the transverse or the build direction, a tensile lattice strain field or a lattice strain field of reduced magnitude is found ahead of the crack tip.

Conclusions

The results indicate that the proposed strategy is well suited to determine the (lattice) strain distributions in the vicinity of fatigue cracks in the center of the specimens with a sufficient lateral resolution.

背景：基于激光的粉末床熔合（PBF-LB/M）是一种制造技术，只要调整工艺参数，就可以根据应用定制组件的特性。然而，该过程会产生残余应变和应力，从而影响疲劳性能。为了分析大量试样中疲劳裂纹附近的残余应变分布，需要较高的横向分辨率，这限制了可能的分析方法只能采用高能同步x射线衍射。目的提出一种可行的策略，以确定通过PBF-LB/M制造的aisi316l压紧试样疲劳裂纹附近的（晶格）应变分布。方法采用角色散锥形缝高能同步加速器x射线衍射装置，将测量体积限制在试样中心。此外，采用增量钻孔法研究了地表附近的残余应力分布。结果沿构筑方向存在较大的残余压应变分布，在裂纹附近残余压应变显著减小。根据裂纹张开方向是与横向对齐还是与构建方向对齐，在裂纹尖端前方存在拉伸晶格应变场或减小幅度的晶格应变场。结论该方法可以较好地确定试件中心疲劳裂纹附近的（点阵）应变分布，且具有足够的横向分辨率。

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引用次数: 0

Documenting Fatigue Crack Nucleation in As-Cast Aluminum Alloy 6082 T6 Heat-Treated Using Digital Image Correlation and Electron Backscatter Diffraction 用数字图像相关和电子背散射衍射记录6082 T6铸态铝合金热处理的疲劳裂纹形核

IF 2.9 3区工程技术 Q2 MATERIALS SCIENCE, CHARACTERIZATION & TESTING

Experimental Mechanics

Pub Date : 2026-06-17 DOI: 10.1007/s11340-026-01333-y

F. V. Ghazvini, Y. Zedan, P. Bocher

Background

Fatigue crack nucleation in as-cast AA6082 remains insufficiently resolved at the microstructural scale, particularly regarding how localized strain and slip-system interactions at grain boundaries and triple junctions govern nucleation.

Objective

This study aims to document the local conditions that lead to crack nucleation, to identify microstructural regions of strain localization, and to evaluate their role in the earliest stages of fatigue damage.

Methods

Full-field digital image correlation (DIC) was employed under cyclic loading to quantify localized deformation, while complementary electron backscatter diffraction (EBSD) provided crystallographic context through grain orientation, Schmid-factor mapping and local strain incompatibilities. The analysis incorporated 3D representations and angular metrics to evaluate geometric (in)compatibility among potentially active slip systems across neighboring grains, with emphasis on triple junctions.

Results

Regions of elevated local deformation frequently coincided with grains of high Schmid factor; however, fatigue crack nucleation occurred only when geometric compatibility was lacking among the possible active slip systems. An extensive study of a fatigue nucleation site reveals that the possible active slip systems in the surrounding grains at the triple junction lack geometric compatibility.

Conclusions

By combining DIC and EBSD, the proposed method establishes a practical framework for describing microscale deformation behavior, clarifies the mechanisms of early crack nucleation in as-cast AA6082, and provides a generalizable approach for other alloys. The approach also enables a statistical perspective based on the probability of critical, geometrically incompatible configurations, informing microstructure-aware fatigue design.

铸态AA6082的疲劳裂纹形核在微观组织尺度上仍然没有得到充分的解决，特别是在晶界和三重结处的局部应变和滑移系统相互作用如何控制形核方面。目的研究导致裂纹成核的局部条件，确定应变局部化的微观组织区域，并评价其在疲劳损伤早期阶段的作用。方法采用全场数字图像相关技术（DIC）对循环载荷下的局部变形进行量化，而互补电子背散射衍射（EBSD）通过晶粒取向、施米德因子映射和局部应变不相容提供晶体学背景。分析结合了三维表示和角度度量来评估相邻颗粒之间潜在活动滑动系统的几何相容性，重点是三重结。结果局部变形增大的区域往往与高施密德因子的晶粒重合；然而，只有在可能的主动滑移体系之间缺乏几何配伍时，才会发生疲劳裂纹形核。对疲劳成核部位的广泛研究表明，在三重结处周围晶粒中可能存在的主动滑移系统缺乏几何相容性。结论该方法结合DIC和EBSD，建立了描述铸态AA6082微尺度变形行为的实用框架，阐明了铸态AA6082早期裂纹形核的机制，为其他合金提供了可推广的方法。该方法还支持基于关键几何不相容配置概率的统计视角，为微结构感知疲劳设计提供信息。

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引用次数: 0

Mechanics-Based Analysis of Interfacial Stress Transfer and Stiffness Stability in Thermoplastic Composites Reinforced with Multi-Source Regenerated Carbon Fibers 基于力学的多源再生碳纤维增强热塑性复合材料界面应力传递及刚度稳定性分析

IF 2.9 3区工程技术 Q2 MATERIALS SCIENCE, CHARACTERIZATION & TESTING

Experimental Mechanics

Pub Date : 2026-06-16 DOI: 10.1007/s11340-026-01335-w

C. L. Chiang, J. H. Chen, P. C. Su, W. T. Feng, M. Y. Shen

Background

The stochastic nature and surface variability of regenerated carbon fibers (rCF) present significant challenges for their reliable application in high-performance structural thermoplastics. Understanding the interplay between fiber architecture and interfacial mechanics is essential for optimizing reinforcement efficiency.

Objective

This study investigates the reinforcing mechanics of rCF with distinct intermediate architectures: a 3D non-woven mat (hereafter referred to as NrCF) and a 2D recycled paper (PrCF) bound by an inert PET binder. The goal is to decouple the intrinsic fiber variability from the macroscopic composite performance using a mechanics-based framework.

Methods

An impregnated fiber bundle tensile test was adapted to isolate the collective strength of the discontinuous fibers. The interfacial stress transfer efficiency and stiffness characteristics of the resulting Polyamide 66 composites were analyzed using the Kelly-Tyson and Cox shear-lag models, respectively. Furthermore, the interfacial confinement effect on thermal stability was quantified via thermogravimetric analysis (TGA).

Results

The NrCF source fibers exhibited a six-fold strength advantage over the PrCF source. Mechanistically, the chemically reactive interface in NrCF significantly enhanced the interfacial shear strength (τ) and reduced the critical fiber length (l_c), enabling efficient stress transfer and superior flexural strength (up to 334.9 MPa). In contrast, the PrCF system exhibited premature failure and matrix-sensitive stiffness due to the weak physical interface governed by the inert binder. Additionally, the robust interfacial bonding in NrCF restricted molecular mobility, significantly delaying thermal degradation compared to the unconstrained PrCF system.

Conclusions

This work demonstrates that for discontinuous regenerated fibers, the restoration of interfacial chemical reactivity is a critical design parameter that outweighs fiber volume fraction in determining structural integrity. The proposed testing protocols and mechanical interpretations provide a rigorous pathway for certifying recycled carbon fiber composites.

再生碳纤维（rCF）的随机性和表面可变性对其在高性能结构热塑性塑料中的可靠应用提出了重大挑战。了解纤维结构和界面力学之间的相互作用对于优化增强效率至关重要。目的：本研究探讨了具有不同中间结构的rCF的增强机制：三维无纺布垫（以下简称NrCF）和由惰性PET粘合剂结合的二维再生纸（PrCF）。目标是使用基于力学的框架将内在纤维可变性与宏观复合材料性能解耦。方法采用浸渍纤维束拉伸试验分离不连续纤维的集体强度。采用Kelly-Tyson和Cox剪切滞后模型分析了聚酰胺66复合材料的界面应力传递效率和刚度特性。此外，通过热重分析（TGA）量化了界面约束对热稳定性的影响。结果NrCF源纤维的强度是PrCF源纤维的6倍。在力学上，NrCF中的化学反应界面显著提高了界面剪切强度（τ），降低了临界纤维长度（lc），实现了有效的应力传递和优异的抗弯强度（高达334.9 MPa）。相比之下，由于惰性粘合剂控制的弱物理界面，PrCF系统表现出过早破坏和基质敏感刚度。此外，与不受约束的PrCF相比，NrCF中强大的界面键限制了分子的迁移性，显著延缓了热降解。本研究表明，对于不连续再生纤维，界面化学反应性的恢复是决定结构完整性的关键设计参数，比纤维体积分数更重要。提出的测试协议和力学解释为认证再生碳纤维复合材料提供了严格的途径。

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引用次数: 0

Speckle Thickness-Dependent Vibration Modes in Dragonfly Wing Membranes: Experiments and Simulations 蜻蜓翼膜中斑点厚度相关的振动模式：实验与模拟

IF 2.9 3区工程技术 Q2 MATERIALS SCIENCE, CHARACTERIZATION & TESTING

Experimental Mechanics

Pub Date : 2026-06-11 DOI: 10.1007/s11340-026-01334-x

Z. Chen, Z. Wang, S. M. Mashimango, H. Zhao, Y. Xu

Background

Using speckles as carriers of surface information has become an essential step in characterizing mechanical properties via digital image correlation (DIC), particularly for measuring morphology, deformation, and vibration parameters of ultra-thin and delicate biological structures.

Objective

This study aims to quantify the effects of speckle coatings on the accuracy of vibration measurements of dragonfly wing membranes, and to provide empirical support and theoretical guidelines for optimizing speckle-based measurement protocols for biological membrane vibration characterization.

Methods

We combined high-speed 3D-DIC vibration measurement technology with image-based finite element (FE) modeling to investigate the effects of three types of speckle coatings on dragonfly wing vibration. The natural frequency, mass change, and vibration mode response were compared between experiments and simulations, with FE models established for wing membranes with different speckle thicknesses to analyze the stiffness-mass coupling effect of speckles.

Results

Experimental results showed that the addition of three types of speckles increased the wing mass by up to ~ 69%, but the natural frequency exhibited an average change of no more than 2 Hz; this phenomenon is attributed to the offset between the mass increase and stiffness enhancement induced by speckle coatings. FE simulations revealed that ultra-thin speckle coatings (≤ 1 μm) caused negligible deviations in low-order natural frequencies (relative error < 0.5%), while thicker layers (≥ 3 μm) led to significant frequency reductions (up to -27.68%) and altered high-order vibration modes, particularly for hindwings with torsion-bending coupling characteristics. The first vibration mode obtained from numerical simulations showed consistent deformation trends with experimental results, dominated by wingtip bending deformation.

Conclusions

Ultra-thin prefabricated speckle coatings (≤ 2 μm) do not significantly alter the low-order natural frequency and fundamental vibration mode of dragonfly wing membranes, as the stiffness enhancement induced by speckles offsets their mass loading effect.

使用斑点作为表面信息的载体已经成为通过数字图像相关（DIC）表征机械性能的重要步骤，特别是用于测量超薄和精致生物结构的形态，变形和振动参数。目的量化散斑涂层对蜻蜓翅膀膜振动测量精度的影响，为优化基于散斑的生物膜振动表征测量方案提供经验支持和理论指导。方法将高速3D-DIC振动测量技术与基于图像的有限元（FE）建模相结合，研究三种散斑涂层对蜻蜓机翼振动的影响。对比了实验与仿真结果的固有频率、质量变化和振型响应，建立了不同散斑厚度机翼膜的有限元模型，分析了散斑的刚度-质量耦合效应。结果实验结果表明，三种斑的加入使机翼质量提高了约69%，但固有频率的平均变化不超过2 Hz；这种现象是由散斑涂层引起的质量增加和刚度增强之间的偏移造成的。有限元模拟表明，超薄散斑涂层（≤1 μm）对低阶固有频率的影响可以忽略不计（相对误差为0.5%），而较厚的散斑涂层（≥3 μm）导致频率显著降低（高达-27.68%），并改变了高阶振动模式，特别是对于具有扭转-弯曲耦合特性的后翼。数值模拟得到的第一种振动模态的变形趋势与实验结果一致，以翼尖弯曲变形为主。结论超薄预制散斑涂层（≤2 μm）对蜻蜓翼膜的低阶固有频率和基振模式没有显著影响，这是由于散斑引起的刚度增强抵消了其质量加载效应。

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引用次数: 0

Robust Finish Machining Induced Residual Stress Characterization via DIC and Statistical Averaging for Incremental Hole Drilling Technique According to ASTM E837 根据ASTM E837，通过DIC和统计平均的增量钻孔技术对坚固精加工引起的残余应力进行表征

IF 2.9 3区工程技术 Q2 MATERIALS SCIENCE, CHARACTERIZATION & TESTING

Experimental Mechanics

Pub Date : 2026-06-10 DOI: 10.1007/s11340-026-01329-8

J. N. Money, A. B. Hartley, C. G. Fuller, J. M. Schoop

Background

Existing methods for quantifying machining-induced residual stress (RS), can be constrained by uncertainties in subsurface stress profiling arising from non-standardized material removal procedures, mechanical gauge misalignment, and long measurement times, limiting the availability of reliable RS data and reducing confidence in subsurface stress evaluation.

Objective

The goal of this work is to develop a digital image correlation (DIC)-based virtual strain gauge (VSG) framework integrated with incremental hole drilling (IHD) to improve fidelity, repeatability, and statistical robustness of full-depth RS measurements in finish-machined Ti-6Al-4V.

Methods

Orthogonal finishing cuts were performed under controlled cutting speed and tool-wear conditions using a custom in-situ testbed. Full-field DIC strain data were processed to generate VSGs emulating ASTM-defined rosettes, enabling strain averaging over large pixel domains and multiple symmetrical locations. Strain–depth profiles from multiple holes were converted to RS using H-Drill software and averaged via the Student’s t-distribution to achieve 95% confidence intervals. Dual-level averaging across strain fields and replicated measurements suppresses DIC noise and measurement scatter inherent in physical gauges.

Results

The averaged RS–depth curves vary with tool flank wear, producing tensile or compressive surface stresses and differing magnitudes and depths of subsurface compression. Combined strain and stress averaging produced smooth, repeatable profiles with accuracy exceeding conventional IHD. The process requires less than 1 h per sub-surface profile.

Conclusions

The DIC-integrated, statistically averaged IHD approach provides a minimally destructive, high-precision, and high-throughput method for quantifying machining-induced RS, enhancing surface integrity characterization and model validation reliability.

现有的加工残余应力（RS）量化方法可能受到非标准化材料去除程序、机械测量偏差和长测量时间引起的地下应力剖面不确定性的限制，从而限制了可靠的RS数据的可用性，降低了对地下应力评估的信心。本研究的目的是开发一种基于数字图像相关（DIC）的虚拟应变计（VSG）框架，结合增量钻孔（IHD），以提高精加工Ti-6Al-4V全深度RS测量的保真度、可重复性和统计稳健性。方法利用定制的原位试验台，在控制切削速度和刀具磨损条件下进行正交精加工。对全场DIC应变数据进行处理，生成模拟astm定义的玫瑰花丛的VSGs，实现大像素域和多个对称位置的应变平均。使用H-Drill软件将多个孔的应变深度剖面转换为RS，并通过Student 's t分布进行平均，以获得95%的置信区间。跨应变场和重复测量的双电平平均抑制了物理测量中固有的DIC噪声和测量散射。结果平均rs -深度曲线随刀具侧面磨损而变化，产生拉伸或压缩表面应力以及不同的次表面压缩强度和深度。结合应变和应力平均产生光滑、可重复的轮廓，精度超过传统的IHD。该过程需要不到1小时每个地下剖面。结论dic集成的统计平均IHD方法提供了一种破坏性最小、高精度、高通量的加工诱导RS定量方法，增强了表面完整性表征和模型验证的可靠性。

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引用次数: 0