{"title":"高应变率动态实验的内部数字图像相关技术","authors":"B.P. Lawlor, V. Gandhi, G. Ravichandran","doi":"10.1007/s11340-025-01149-2","DOIUrl":null,"url":null,"abstract":"<div><h3>Background</h3><p>Full-field, quantitative visualization techniques, such as digital image correlation (DIC), have unlocked vast opportunities for experimental mechanics. However, DIC has traditionally been a surface measurement technique, and has not been extended to perform measurements on the interior of specimens for dynamic, full-scale laboratory experiments. This limitation restricts the scope of physics which can be investigated through DIC measurements, especially in the context of heterogeneous materials.</p><h3>Objective</h3><p>The focus of this study is to develop a method for performing internal DIC measurements in dynamic experiments. The aim is to demonstrate its feasibility and accuracy across a range of stresses (up to <span>\\(650\\,\\)</span>MPa), strain rates (<span>\\(10^{3}\\)</span>-<span>\\(10^6\\,\\)</span>s<span>\\(^{-1}\\)</span>), and high-strain rate loading conditions (e.g., ramped and shock wave loading).</p><h3>Methods</h3><p>Internal DIC is developed based on the concept of applying a speckle pattern at an inner-plane of a transparent specimen. The high-speed imaging configuration is coupled to the traditional dynamic experimental setups, and is focused on the internal speckle pattern. During the experiment, while the sample deforms dynamically, in-plane, two-dimensional deformations are measured via correlation of the internal speckle pattern. In this study, the viability and accuracy of the internal DIC technique is demonstrated for split-Hopkinson (Kolsky) pressure bar (SHPB) and plate impact experiments.</p><h3>Results</h3><p>The internal DIC experimental technique is successfully demonstrated in both the SHPB and plate impact experiments. In the SHPB setting, the accuracy of the technique is excellent throughout the deformation regime, with measurement noise of approximately <span>\\(0.2\\%\\)</span> strain. In the case of plate impact experiments, the technique performs well, with error and measurement noise of <span>\\(1\\%\\)</span> strain.</p><h3>Conclusion</h3><p>The internal DIC technique has been developed and demonstrated to work well for full-scale dynamic high-strain rate and shock laboratory experiments, and the accuracy is quantified. The technique can aid in investigating the physics and mechanics of the dynamic behavior of materials, including local deformation fields around dynamically loaded material heterogeneities.</p></div>","PeriodicalId":552,"journal":{"name":"Experimental Mechanics","volume":"65 3","pages":"407 - 419"},"PeriodicalIF":2.0000,"publicationDate":"2025-02-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"An Internal Digital Image Correlation Technique for High-Strain Rate Dynamic Experiments\",\"authors\":\"B.P. Lawlor, V. Gandhi, G. Ravichandran\",\"doi\":\"10.1007/s11340-025-01149-2\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><h3>Background</h3><p>Full-field, quantitative visualization techniques, such as digital image correlation (DIC), have unlocked vast opportunities for experimental mechanics. However, DIC has traditionally been a surface measurement technique, and has not been extended to perform measurements on the interior of specimens for dynamic, full-scale laboratory experiments. This limitation restricts the scope of physics which can be investigated through DIC measurements, especially in the context of heterogeneous materials.</p><h3>Objective</h3><p>The focus of this study is to develop a method for performing internal DIC measurements in dynamic experiments. The aim is to demonstrate its feasibility and accuracy across a range of stresses (up to <span>\\\\(650\\\\,\\\\)</span>MPa), strain rates (<span>\\\\(10^{3}\\\\)</span>-<span>\\\\(10^6\\\\,\\\\)</span>s<span>\\\\(^{-1}\\\\)</span>), and high-strain rate loading conditions (e.g., ramped and shock wave loading).</p><h3>Methods</h3><p>Internal DIC is developed based on the concept of applying a speckle pattern at an inner-plane of a transparent specimen. The high-speed imaging configuration is coupled to the traditional dynamic experimental setups, and is focused on the internal speckle pattern. During the experiment, while the sample deforms dynamically, in-plane, two-dimensional deformations are measured via correlation of the internal speckle pattern. In this study, the viability and accuracy of the internal DIC technique is demonstrated for split-Hopkinson (Kolsky) pressure bar (SHPB) and plate impact experiments.</p><h3>Results</h3><p>The internal DIC experimental technique is successfully demonstrated in both the SHPB and plate impact experiments. In the SHPB setting, the accuracy of the technique is excellent throughout the deformation regime, with measurement noise of approximately <span>\\\\(0.2\\\\%\\\\)</span> strain. In the case of plate impact experiments, the technique performs well, with error and measurement noise of <span>\\\\(1\\\\%\\\\)</span> strain.</p><h3>Conclusion</h3><p>The internal DIC technique has been developed and demonstrated to work well for full-scale dynamic high-strain rate and shock laboratory experiments, and the accuracy is quantified. The technique can aid in investigating the physics and mechanics of the dynamic behavior of materials, including local deformation fields around dynamically loaded material heterogeneities.</p></div>\",\"PeriodicalId\":552,\"journal\":{\"name\":\"Experimental Mechanics\",\"volume\":\"65 3\",\"pages\":\"407 - 419\"},\"PeriodicalIF\":2.0000,\"publicationDate\":\"2025-02-06\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Experimental Mechanics\",\"FirstCategoryId\":\"5\",\"ListUrlMain\":\"https://link.springer.com/article/10.1007/s11340-025-01149-2\",\"RegionNum\":3,\"RegionCategory\":\"工程技术\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q2\",\"JCRName\":\"MATERIALS SCIENCE, CHARACTERIZATION & TESTING\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Experimental Mechanics","FirstCategoryId":"5","ListUrlMain":"https://link.springer.com/article/10.1007/s11340-025-01149-2","RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"MATERIALS SCIENCE, CHARACTERIZATION & TESTING","Score":null,"Total":0}
引用次数: 0
摘要
全视野、定量可视化技术,如数字图像相关(DIC),为实验力学打开了巨大的机会。然而,DIC传统上是一种表面测量技术,并没有扩展到在动态的、全尺寸的实验室实验中对标本内部进行测量。这种限制限制了通过DIC测量可以研究的物理范围,特别是在非均质材料的背景下。目的本研究的重点是开发一种在动态实验中进行内部DIC测量的方法。目的是证明其在一系列应力(高达\(650\,\) MPa),应变率(\(10^{3}\) - \(10^6\,\) s \(^{-1}\))和高应变率加载条件(例如,斜坡和冲击波加载)下的可行性和准确性。方法基于在透明标本的内平面上应用散斑图案的概念,开发了内部DIC。高速成像配置与传统的动态实验设置相耦合,并专注于内部散斑模式。在实验过程中,在样品动态变形的同时,通过内部散斑图的相关测量平面内二维变形。在本研究中,通过split-Hopkinson (Kolsky)压力棒(SHPB)和钢板撞击实验证明了内DIC技术的可行性和准确性。结果内部DIC实验技术在SHPB和平板撞击实验中都得到了成功的验证。在SHPB环境下,该技术在整个变形过程中的精度都很好,测量噪声约为\(0.2\%\)应变。在平板冲击实验中,该技术表现良好,但存在\(1\%\)应变的误差和测量噪声。结论内部DIC技术在全尺寸动态高应变率和冲击实验中具有良好的应用效果,其准确性得到了量化。该技术可以帮助研究材料动态行为的物理和力学,包括动态加载材料异质周围的局部变形场。
An Internal Digital Image Correlation Technique for High-Strain Rate Dynamic Experiments
Background
Full-field, quantitative visualization techniques, such as digital image correlation (DIC), have unlocked vast opportunities for experimental mechanics. However, DIC has traditionally been a surface measurement technique, and has not been extended to perform measurements on the interior of specimens for dynamic, full-scale laboratory experiments. This limitation restricts the scope of physics which can be investigated through DIC measurements, especially in the context of heterogeneous materials.
Objective
The focus of this study is to develop a method for performing internal DIC measurements in dynamic experiments. The aim is to demonstrate its feasibility and accuracy across a range of stresses (up to \(650\,\)MPa), strain rates (\(10^{3}\)-\(10^6\,\)s\(^{-1}\)), and high-strain rate loading conditions (e.g., ramped and shock wave loading).
Methods
Internal DIC is developed based on the concept of applying a speckle pattern at an inner-plane of a transparent specimen. The high-speed imaging configuration is coupled to the traditional dynamic experimental setups, and is focused on the internal speckle pattern. During the experiment, while the sample deforms dynamically, in-plane, two-dimensional deformations are measured via correlation of the internal speckle pattern. In this study, the viability and accuracy of the internal DIC technique is demonstrated for split-Hopkinson (Kolsky) pressure bar (SHPB) and plate impact experiments.
Results
The internal DIC experimental technique is successfully demonstrated in both the SHPB and plate impact experiments. In the SHPB setting, the accuracy of the technique is excellent throughout the deformation regime, with measurement noise of approximately \(0.2\%\) strain. In the case of plate impact experiments, the technique performs well, with error and measurement noise of \(1\%\) strain.
Conclusion
The internal DIC technique has been developed and demonstrated to work well for full-scale dynamic high-strain rate and shock laboratory experiments, and the accuracy is quantified. The technique can aid in investigating the physics and mechanics of the dynamic behavior of materials, including local deformation fields around dynamically loaded material heterogeneities.
期刊介绍:
Experimental Mechanics is the official journal of the Society for Experimental Mechanics that publishes papers in all areas of experimentation including its theoretical and computational analysis. The journal covers research in design and implementation of novel or improved experiments to characterize materials, structures and systems. Articles extending the frontiers of experimental mechanics at large and small scales are particularly welcome.
Coverage extends from research in solid and fluids mechanics to fields at the intersection of disciplines including physics, chemistry and biology. Development of new devices and technologies for metrology applications in a wide range of industrial sectors (e.g., manufacturing, high-performance materials, aerospace, information technology, medicine, energy and environmental technologies) is also covered.