Experimental Mechanics最新文献_第3页

Tuning Energy Absorption of Metallic TPMS Cellular Structures via Wall Thickness Gradient Design 基于壁厚梯度设计的金属TPMS细胞结构的能量吸收调谐

IF 2.4 3区工程技术

Experimental Mechanics Pub Date : 2025-05-15 DOI: 10.1007/s11340-025-01190-1

M. Zhong, W. Zhou, Z. Wu, J. Deng, Y. Du

{"title":"Tuning Energy Absorption of Metallic TPMS Cellular Structures via Wall Thickness Gradient Design","authors":"M. Zhong, W. Zhou, Z. Wu, J. Deng, Y. Du","doi":"10.1007/s11340-025-01190-1","DOIUrl":"10.1007/s11340-025-01190-1","url":null,"abstract":"<div><h3>Background</h3><p>In the study of laser melting fabricated 316L stainless steel triply periodic minimal surface (TPMS) structures, a knowledge gap persists. The understanding of optimizing deformation mechanisms and energy absorption, especially via gradient wall thickness design, remains inadequate.</p><h3>Objective</h3><p>The main aim of this research is to explore the deformation and energy absorption features of particular 316L stainless steel TPMS structures made by laser melting, emphasizing the use of gradient wall thickness design to improve overall energy absorption.</p><h3>Methods</h3><p>An integrated experimental and computational approach was developed. TPMS structures with diverse wall thicknesses were fabricated through laser melting. Then, detailed analyses were performed to examine stress and deformation under compression. The novelty was the local strategies in gradient wall thickness design for enhanced stress redistribution.</p><h3>Results</h3><p>Quantitatively, compared to uniform ones, the specific energy absorption (SEA) of gradient structures rose by 18.3% along the loading direction and 26.8% perpendicular to diagonal shearing. Qualitatively, the gradient design reduced early densification and improved stress redistribution, yielding new insights for future designs.</p><h3>Conclusions</h3><p>Overall, the strategic use of gradient design and wall thickness control significantly boosts the SEA of laser melting fabricated 316L stainless steel TPMS structures, showing great potential for future applications.</p></div>","PeriodicalId":552,"journal":{"name":"Experimental Mechanics","volume":"65 7","pages":"1043 - 1054"},"PeriodicalIF":2.4,"publicationDate":"2025-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144843306","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Study on the Long-Term Monitoring of Contact Deformation Field of Periodic Rotating Gears Using DIC Combined with SURF Algorithm 基于DIC与SURF算法的周期旋转齿轮接触变形场长期监测研究

IF 2.4 3区工程技术

Experimental Mechanics Pub Date : 2025-05-15 DOI: 10.1007/s11340-025-01189-8

X. Hou, D. Zeng, X. Huang, H. Zhang, Z. Liu, X. Huang

{"title":"Study on the Long-Term Monitoring of Contact Deformation Field of Periodic Rotating Gears Using DIC Combined with SURF Algorithm","authors":"X. Hou, D. Zeng, X. Huang, H. Zhang, Z. Liu, X. Huang","doi":"10.1007/s11340-025-01189-8","DOIUrl":"10.1007/s11340-025-01189-8","url":null,"abstract":"<div><h3>Background</h3><p>Digital image correlation (DIC) is a widely adopted non-contact method for precise motion and deformation measurement, valued for its high accuracy. However, standard 2D DIC struggles to track relative displacements in materials with significant rigid rotations or out-of-plane displacement interference, such as in monitoring rotating gears. Additionally, the extensive data generated during in-situ monitoring makes DIC-based image matching impractical.</p><h3>Objective</h3><p>This study proposes a method for rapidly identifying identical images from large datasets. The proposed method can also effectively eliminate the impact of rigid rotation and out-of-plane displacement.</p><h3>Methods</h3><p>This study proposes a dynamic period digital image correlation (DP-DIC) method. The technique utilizes the speeded-up robust features (SURF) algorithm to match and select feature points efficiently, addressing the issue of image decorrelation caused by large-angle rotations. Furthermore, a rigid-body matrix restoration algorithm is incorporated to reduce the effects of rigid rotation and out-of-plane displacement partially.</p><h3>Results</h3><p>Validation tests for measuring the dynamic deformation field of rotating gears provide essential data. This data supports gear design optimization, performance evaluation, and lifetime prediction.</p><h3>Conclusion</h3><p>This study proposes a DP-DIC method based on DIC. Validation tests demonstrate that the DP-DIC method is suitable for long-term monitoring of the contact deformation field in periodically rotating gears.</p></div>","PeriodicalId":552,"journal":{"name":"Experimental Mechanics","volume":"65 7","pages":"1055 - 1068"},"PeriodicalIF":2.4,"publicationDate":"2025-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144843307","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Quantifying the Optimal Two-Step Photocuring Protocol for Maximally Reduced Shrinkage Stress during Photopolymerization 量化光聚合过程中最大限度减少收缩应力的最佳两步光固化方案

IF 2.4 3区工程技术

Experimental Mechanics Pub Date : 2025-05-13 DOI: 10.1007/s11340-025-01193-y

L. Bao, K. Wang, Z. Wang

{"title":"Quantifying the Optimal Two-Step Photocuring Protocol for Maximally Reduced Shrinkage Stress during Photopolymerization","authors":"L. Bao, K. Wang, Z. Wang","doi":"10.1007/s11340-025-01193-y","DOIUrl":"10.1007/s11340-025-01193-y","url":null,"abstract":"<div><h3>Background</h3><p>Shrinkage stress accumulated during photopolymerization significantly impairs the quality and lifespan of photopolymerized materials. Soft-start photocuring protocols like ramp, two-step, and pulse-delay have been proposed to mitigate this issue, among which the two-step protocol has been proved to be the most effective. However, the accuracy and underlying mechanisms of the previously proposed strategy for quantifying the optimal two-step protocol have not been validated.</p><h3>Objective</h3><p>In this study, the universality of the strategy for quantifying the optimal two-step photocuring protocol was validated experimentally under varying working conditions, and the mechanism was systematically investigated to correct previous conjectures.</p><h3>Methods</h3><p>Shrinkage stress and reaction temperature of typical methacrylate resins during photopolymerization were measured under various working conditions (irradiation intensity, stiffness of constraint, and particle filling content of the testing material) using a standardized cantilever beam instrument.</p><h3>Results</h3><p>The optimal first irradiation time and delay time were identified based on the initiation of the stress evolution and the inflection point where shrinkage stress stabilized under the standard protocol, respectively. This optimal protocol resulted in a 20%-40% reduction in the shrinkage stress across all the working conditions tested with the shortest total curing duration. The stress reduction can be attributed to delayed gelation and a lower peak temperature change after gelation.</p><h3>Conclusions</h3><p>The present study not only validates the broad applicability of the optimal two-step curing protocol for maximally-reduced shrinkage stress, it also uncovers the underlying mechanism that should guide the manufacturing and application of photopolymers for improved service quality and longevity.</p></div>","PeriodicalId":552,"journal":{"name":"Experimental Mechanics","volume":"65 7","pages":"1031 - 1042"},"PeriodicalIF":2.4,"publicationDate":"2025-05-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144843292","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Characterization of Polymerization Shrinkage Behavior in Photocurable Resins Using Digital Image Correlation 利用数字图像相关技术表征光固化树脂的聚合收缩行为

IF 2.4 3区工程技术

Experimental Mechanics Pub Date : 2025-05-13 DOI: 10.1007/s11340-025-01191-0

Q. Lin, X. Zhang, X. Sun, B. Zhang, W. Liu, Y. Wu, Y. Huang, J. Zhu, N. Zhao, Q. Li

{"title":"Characterization of Polymerization Shrinkage Behavior in Photocurable Resins Using Digital Image Correlation","authors":"Q. Lin, X. Zhang, X. Sun, B. Zhang, W. Liu, Y. Wu, Y. Huang, J. Zhu, N. Zhao, Q. Li","doi":"10.1007/s11340-025-01191-0","DOIUrl":"10.1007/s11340-025-01191-0","url":null,"abstract":"<div><h3>Background</h3><p>Photocurable resins are widely used in industrial production, but the polymerization shrinkage that occurs during their curing process generates adverse polymerization shrinkage stresses within the material and at the interface between the material and the substrate, which can affect the performance of the photocurable resin material.</p><h3>Objective</h3><p>Measuring the polymerization shrinkage and the associated shrinkage stress not only allows for the evaluation of the material’s performance but also helps to research and develop the photocurable resin. Furthermore, it could help to analyze the failure mechanisms of the service process of the resin and enables the active control of polymerization shrinkage stress.</p><h3>Methods</h3><p>We employ Digital Image Correlation to actively measure the polymerization shrinkage of photocurable resins. Basing on the experimental results, multi-physics simulation analysis was conducted, successfully establishing a curing model for photocurable resins.</p><h3>Results</h3><p>The measurement results indicate that increasing the amount of photoinitiator reduces polymerization shrinkage stress, changes in ultraviolet light incident energy do not significantly affect the polymerization shrinkage stress. For simulation’s results, the maximum error in stress–strain comparison between the simulation model and the experimental model is no more than 10%, with the minimum error being 2.7%, confirming the accuracy of the simulation model.</p><h3>Conclusion</h3><p>The contactless characterization technique successfully measures polymer shrinkage strain and the simulation’s curing model for photocurable resins shows high agreement of experiment, which provides insights for the experimental design and theoretical study of shrinkage stress in photocurable resins. It offers some reference for the design of photocurable resin used in electronic packaging.</p></div>","PeriodicalId":552,"journal":{"name":"Experimental Mechanics","volume":"65 7","pages":"1011 - 1029"},"PeriodicalIF":2.4,"publicationDate":"2025-05-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144843291","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Acoustic Emission Behavior of Carbon Fiber Bundle Under Tensile Load 拉伸载荷下碳纤维束的声发射特性

IF 2.4 3区工程技术

Experimental Mechanics Pub Date : 2025-05-13 DOI: 10.1007/s11340-025-01192-z

Z. Yang, G. Fang

{"title":"Acoustic Emission Behavior of Carbon Fiber Bundle Under Tensile Load","authors":"Z. Yang, G. Fang","doi":"10.1007/s11340-025-01192-z","DOIUrl":"10.1007/s11340-025-01192-z","url":null,"abstract":"<div><h3>Background</h3><p>Acoustic emission (AE) is widely used to study the progressive damage of composite materials. Traditionally, the AE method focuses on assessing structural damage by experimentally testing AE signals. However, the application of mechanical methods to theoretically predict AE signals during the progressive damage process of dry fiber bundles has been limited.</p><h3>Objective</h3><p>The primary objective of this study is to establish a theoretical method for predicting AE signals during the tensile fracture process of dry fiber bundles.</p><h3>Methods</h3><p>This model comprises three key components: (1) Single Fiber Fracture Dynamics Model: This component analyzes the motion of the fracture cross-section at the moment of fiber breakage. (2) Point Sound Source Model: Utilizing the motion of fiber cross-sections as a source, this model analyzes the acoustic signals generated during one single fiber fractures. (3) Monte Carlo Model: This model simulates the progressive fracture of the dry fiber bundle by aggregating the AE signals from individual fiber fractures. It generates a comprehensive time-domain signal profile by summing the contributions from each fracture event.</p><h3>Results</h3><p>To validate the model's effectiveness and accuracy, a comparison was made with existing prediction models and available experimental data. The experimental results were found to be in good agreement with the theoretical predictions.</p><h3>Conclusion</h3><p>This theoretical model has been thoroughly validated and can be applied to analyze AE signals in other brittle dry fiber bundles, providing valuable insights into their fracture behaviors.</p></div>","PeriodicalId":552,"journal":{"name":"Experimental Mechanics","volume":"65 7","pages":"999 - 1009"},"PeriodicalIF":2.4,"publicationDate":"2025-05-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144843290","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Thermal Expansion Coefficient Measurement of Stack Structure of REBCO Coated Conductors By Strain Gages At Cryogenic Temperatures 低温下应变片测量REBCO涂层导体堆叠结构的热膨胀系数

IF 2.4 3区工程技术

Experimental Mechanics Pub Date : 2025-05-09 DOI: 10.1007/s11340-025-01187-w

C. Liu, C. Ma, Y. Shi, J. Zhou

{"title":"Thermal Expansion Coefficient Measurement of Stack Structure of REBCO Coated Conductors By Strain Gages At Cryogenic Temperatures","authors":"C. Liu, C. Ma, Y. Shi, J. Zhou","doi":"10.1007/s11340-025-01187-w","DOIUrl":"10.1007/s11340-025-01187-w","url":null,"abstract":"<div><h3>Background</h3><p>The structures of stack REBa<sub>2</sub>Cu<sub>3</sub>O<sub>7-x</sub> (RE: rare earth elements) coated conductors (CCs), with epoxy impregnated, are commonly involved in superconducting cables and pancake magnet coils. Thermal stresses are inevitable in the stack structures because of the mismatch of coefficient of thermal expansion (CTE) between the CCs and epoxy at cryogenic temperatures.</p><h3>Objective</h3><p>It is essential to precisely measure the thermal deformation of the stack structure such that to determine the corresponding CTE. Here, a protocol for determine the CTE by strain gages was reported.</p><h3>Methods</h3><p>Copper was used as a standard reference material, and its cryogenic thermal expansion curve was determined by the digital image correlation method. This curve was then used to correct the thermal deformation curves of the testing samples, eliminating the heat output of the strain gage itself.</p><h3>Results</h3><p>Thermal deformation of an aluminum beam has been measured with a relative error of less than 5% compared to that from the National Institute of Standards and Technology of the United States. The maximum thermal deformation of the stack sample along the thickness direction was almost 4.5 times of those along other two orthogonal directions.</p><h3>Conclusions</h3><p>The approach presented was validated by the aluminum test, CTE for stack structure along the thickness direction was found to be larger than those along other two orthogonal directions.</p></div>","PeriodicalId":552,"journal":{"name":"Experimental Mechanics","volume":"65 6","pages":"981 - 989"},"PeriodicalIF":2.4,"publicationDate":"2025-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145163538","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

On the Cover: Plasticity Bridges Microscale Martensitic Shear Bands in Superelastic Nitinol 封面：超弹性镍钛诺中微尺度马氏体剪切带的塑性桥梁

IF 2 3区工程技术

Experimental Mechanics Pub Date : 2025-04-30 DOI: 10.1007/s11340-025-01188-9

引用次数: 0

Improving Reversed Three-Point Bending Tests for Characterising the Fatigue Life of Polymers 改进了表征聚合物疲劳寿命的反向三点弯曲试验

IF 2.4 3区工程技术

Experimental Mechanics Pub Date : 2025-04-23 DOI: 10.1007/s11340-025-01184-z

S. Baril-Gosselin

{"title":"Improving Reversed Three-Point Bending Tests for Characterising the Fatigue Life of Polymers","authors":"S. Baril-Gosselin","doi":"10.1007/s11340-025-01184-z","DOIUrl":"10.1007/s11340-025-01184-z","url":null,"abstract":"<div><h3>Background</h3><p>Cyclic loading is a leading cause of material failure and accurate testing methods are required to predict the life of components.</p><h3>Objective</h3><p>This work investigated the challenges of performing reversed three-point bending experiments for characterising the fatigue life of polymers and composites, and sought to develop guidelines for improving the testing method.</p><h3>Methods</h3><p>Testing was performed with polypropylene (PP) and glass-fibre reinforced PP on a test fixture that featured double-sided supports. Monotonic and fully reversed (i.e. stress ratio <i>R</i> = - 1) cyclic bending experiments were conducted to characterise the effects that the test conditions, including the type of supports and level of contact between the specimens and anvils, have on the measurements.</p><h3>Results</h3><p>Stresses generated during reversed bending are highly dependent on the type of fixture configuration used. Most configurations that were tested led to mechanical interlocking that altered the bending moments and generated membrane stresses. In this work, the purest form of reversed bending was achieved using double-sided pivoting supports, and a 0.35 mm gap between specimens and anvils to allow sliding in the supports.</p><h3>Conclusions</h3><p>This configuration provided the most similar stress state to that obtained from the standardised simply-supported beam experiments that are used for characterising the quasi-static flexural properties of materials, and was ultimately the configuration that provided the most reliable fatigue data.</p></div>","PeriodicalId":552,"journal":{"name":"Experimental Mechanics","volume":"65 6","pages":"969 - 980"},"PeriodicalIF":2.4,"publicationDate":"2025-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s11340-025-01184-z.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145168701","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Mechanical Characterization of Additive-Manufactured Ti-6Al-4V Processed via Bound Metal Deposition 结合金属沉积增材制造Ti-6Al-4V的力学特性

IF 2 3区工程技术

Experimental Mechanics Pub Date : 2025-04-23 DOI: 10.1007/s11340-025-01178-x

E. Devine, M. Lester, T. McElroy, T. Valenzuela, W. LePage

{"title":"Mechanical Characterization of Additive-Manufactured Ti-6Al-4V Processed via Bound Metal Deposition","authors":"E. Devine, M. Lester, T. McElroy, T. Valenzuela, W. LePage","doi":"10.1007/s11340-025-01178-x","DOIUrl":"10.1007/s11340-025-01178-x","url":null,"abstract":"<div><h3>Background</h3><p>Additive manufacturing (AM) is rapidly growing, with new AM methods continually in development. Alloys processed with novel methods require systematic characterization to understand and validate the materials, especially for demanding fields.</p><h3>Objective</h3><p>This study characterized the mechanical properties and failure mechanisms of a Ti-6Al-4V alloy manufactured with bound metal deposition (BMD), a form of metal extrusion (MEX) AM.</p><h3>Methods</h3><p>Specimens made of Ti64 were printed via Desktop Metal’s Studio System 2 through a printing, debinding, and sintering process. The microstructure was analyzed with optical metallography and a newly developed open-source porosity analysis tool. Scanning electron microscopy (SEM), optical microscopy, and compositional analysis of green, brown, and sintered parts were conducted to study the material and its failure modes. Sintered specimens were tensile and hardness tested.</p><h3>Results</h3><p>As-sintered specimens exhibited ductility more than 10 times lower than wrought Ti64, partially due to contamination/impurity that formed brittle <span>(alpha )</span>-case titanium. Sources of contamination may have included the sacrificial Al<span>(_2)</span>O<span>(_3)</span> interlayer, the wax/polymer binder, and/or impurity introduction from the furnace. Fractography imaging found quasi-cleavage fracture initiating at areas of high surface roughness along the ceramic interlayer surface of the parts and transitioning into dimple rupture and intergranular decohesion.</p><h3>Conclusions</h3><p>Elevated contamination levels, high surface roughness, and internal porosity led to low elongation and ultimate strength in the Ti64 BMD alloy. With the processing route presented here, BMD for Ti64 may not be suitable for applications that demand high ductility and strength with minimal impurities, although with process refinement, the method may be promising for certain applications</p></div>","PeriodicalId":552,"journal":{"name":"Experimental Mechanics","volume":"65 4","pages":"573 - 596"},"PeriodicalIF":2.0,"publicationDate":"2025-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143919006","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Mechanics of Additively Manufactured Materials 增材制造材料力学

IF 2 3区工程技术

Experimental Mechanics Pub Date : 2025-04-23 DOI: 10.1007/s11340-025-01181-2

L.R. Xu, G. J. Pataky

引用次数: 0