Experimental Mechanics最新文献_第6页

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 Q2 MATERIALS SCIENCE, CHARACTERIZATION & TESTING

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

Background

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.

Objective

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.

Methods

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.

Results

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.

Conclusion

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.

数字图像相关（DIC）是一种被广泛采用的用于精确运动和变形测量的非接触方法，其精度高。然而，标准的2D DIC难以跟踪具有明显刚性旋转或面外位移干扰的材料中的相对位移，例如监测旋转齿轮。此外，现场监测过程中产生的大量数据使得基于dic的图像匹配不切实际。目的提出一种从大数据集中快速识别相同图像的方法。该方法还可以有效地消除刚性旋转和面外位移的影响。方法提出一种动态周期数字图像相关（DP-DIC）方法。该技术利用加速鲁棒特征（SURF）算法有效匹配和选择特征点，解决了大角度旋转引起的图像去相关问题。在此基础上，引入刚体矩阵恢复算法，部分降低了刚体旋转和面外位移的影响。结果验证试验为测量旋转齿轮动态变形场提供了必要的数据。这些数据支持齿轮设计优化，性能评估和寿命预测。结论本研究提出了一种基于DIC的DP-DIC方法。验证试验表明，DP-DIC方法适用于周期旋转齿轮接触变形场的长期监测。

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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 Q2 MATERIALS SCIENCE, CHARACTERIZATION & TESTING

Experimental Mechanics

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

L. Bao, K. Wang, Z. Wang

Background

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.

Objective

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.

Methods

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.

Results

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.

Conclusions

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.

光聚合过程中积累的收缩应力会严重影响光聚合材料的质量和使用寿命。为了缓解这一问题，人们提出了一些软启动光固化协议，如斜坡、两步和脉冲延迟，其中两步协议已被证明是最有效的。然而，先前提出的量化最优两步协议的策略的准确性和潜在机制尚未得到验证。目的在不同的工作条件下，通过实验验证两步光固化最佳方案量化策略的通用性，并对其机理进行系统的探讨，以纠正以往的猜想。方法采用标准悬臂梁式测量仪，测量了典型甲基丙烯酸酯树脂在不同工作条件下（辐照强度、约束刚度和测试材料颗粒填充量）光聚合过程中的收缩应力和反应温度。结果根据应力演化起始点和标准方案下收缩应力稳定拐点确定了最佳的首次辐照时间和延迟时间。在最短的总固化时间内，在所有测试的工作条件下，这种最佳方案使收缩应力降低了20%-40%。应力的减小可归因于胶凝延迟和胶凝后温度变化峰值的降低。结论本研究不仅验证了最佳两步固化方案在最大限度地降低收缩应力方面的广泛适用性，而且揭示了指导光聚合物制造和应用以提高使用质量和寿命的潜在机制。

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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 Q2 MATERIALS SCIENCE, CHARACTERIZATION & TESTING

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

Background

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.

Objective

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.

Methods

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.

Results

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.

Conclusion

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.

背景光固化树脂广泛应用于工业生产，但其固化过程中发生的聚合收缩会在材料内部和材料与基材界面处产生不良的聚合收缩应力，从而影响光固化树脂材料的性能。目的测定聚合收缩率及其相关的收缩应力，不仅可以评价材料的性能，而且有助于光固化树脂的研究和开发。进一步分析了树脂在使用过程中的失效机理，实现了对聚合收缩应力的主动控制。方法采用数字图像相关技术主动测量光固化树脂的聚合收缩率。在实验结果的基础上，进行了多物理场模拟分析，成功建立了光固化树脂的固化模型。结果光引发剂用量的增加可降低聚合收缩应力，紫外光入射能量的变化对聚合收缩应力影响不显著。仿真结果表明，仿真模型与实验模型的应力应变对比最大误差不大于10%，最小误差为2.7%，验证了仿真模型的准确性。结论采用非接触式表征技术成功地测量了聚合物的收缩应变，所建立的光固化树脂的模拟固化模型具有较高的实验一致性，为光固化树脂收缩应力的实验设计和理论研究提供了参考。为电子封装用光固化树脂的设计提供参考。

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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 Q2 MATERIALS SCIENCE, CHARACTERIZATION & TESTING

Experimental Mechanics

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

Z. Yang, G. Fang

Background

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.

Objective

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.

Methods

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.

Results

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.

Conclusion

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.

背景声发射（AE）被广泛用于研究复合材料的渐进损伤。传统的声发射方法侧重于通过实验测试声发射信号来评估结构损伤。然而，利用力学方法对干纤维束渐进损伤过程中的声发射信号进行理论预测还存在一定的局限性。目的建立一种预测干纤维束拉伸断裂过程声发射信号的理论方法。方法该模型由三个关键部分组成：(1)单纤维断裂动力学模型：该模型分析纤维断裂时刻断裂截面的运动。(2)点声源模型：该模型以纤维截面运动为源，分析单个纤维断裂时产生的声信号。(3)蒙特卡罗模型（Monte Carlo Model）：该模型通过汇总来自单个纤维断裂的声发射信号来模拟干纤维束的渐进断裂。它通过汇总每个裂缝事件的贡献来生成一个全面的时域信号剖面。结果为了验证模型的有效性和准确性，将模型与已有的预测模型和实验数据进行了比较。实验结果与理论预测相吻合。结论该理论模型已得到充分验证，可用于分析其他脆性干纤维束的声发射信号，为其断裂行为提供有价值的见解。

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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 Q2 MATERIALS SCIENCE, CHARACTERIZATION & TESTING

Experimental Mechanics

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

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

Background

The structures of stack REBa₂Cu₃O_7-x (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.

Objective

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.

Methods

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.

Results

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.

Conclusions

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.

REBa2Cu3O7-x （REBa2Cu3O7-x, RE: rare earth elements）涂层导体（CCs）是一种环氧浸渍的叠层结构，通常用于超导电缆和烙饼磁体线圈中。低温下，碳纤维与环氧树脂之间的热膨胀系数（CTE）不匹配，导致叠层结构不可避免地存在热应力。目的精确测量叠层结构的热变形，以确定相应的CTE。本文报道了一种用应变片测定CTE的方法。方法以scopper为标准对照品，采用数字图像相关法测定其低温热膨胀曲线。然后使用该曲线来校正测试样品的热变形曲线，消除应变片本身的热输出。结果铝梁的热变形测量结果与美国国家标准与技术研究院的测量结果相对误差小于5%。叠层试样沿厚度方向的最大热变形几乎是沿其他两个正交方向的4.5倍。结论该方法得到了铝材试验的验证，叠层结构沿厚度方向的CTE值大于其他两个正交方向。

{"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 Q2 MATERIALS SCIENCE, CHARACTERIZATION & TESTING

Experimental Mechanics

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

引用次数: 0

Collapse Behavior of Cylindrical Shells with Anticlastic Curvature Sections 具有抗裂曲率截面的圆柱壳的坍塌行为

IF 2.4 3区工程技术 Q2 MATERIALS SCIENCE, CHARACTERIZATION & TESTING

Experimental Mechanics

Pub Date : 2025-04-28 DOI: 10.1007/s11340-025-01186-x

A. Pandey, D. Fontaine, A. Shukla

Background

Understanding the dynamic buckling behavior of cylindrical shells is crucial for various marine engineering applications including underwater pipelines, yet the influence of concave circumferential grooves on their collapse capacity remains underexplored.

Objective

This study aims to investigate the effect of groove geometry on the dynamic buckling behavior of aluminum tubes under hydrostatic pressure.

Methods

Experiments were conducted in a water-filled pressure vessel facility, utilizing high-speed imaging with 3D Digital Image Correlation and piezoelectric transducers to capture transient collapse behavior of cylindrical shells and associated local pressure histories. Finite element simulations complemented the experiments to analyze critical pressure sensitivity to groove wall thickness.

Results

The presence of a mid-length groove increased collapse capacity by 25% to 50% compared to non-grooved tubes and reduced peak dynamic overpressure. Groove depth significantly influenced failure mode: deeper grooves induced local buckling, while shallow grooves led to global collapse. Simulations further demonstrated collapse capacity improvements reaching up to 65% for tubes with a groove.

Conclusions

Introducing a concave circumferential groove enhances the collapse resistance of cylindrical shells, with geometric configuration playing a pivotal role in determining failure mode.

了解圆柱壳的动态屈曲行为对于包括水下管道在内的各种海洋工程应用至关重要，但凹周向凹槽对其破坏能力的影响仍未得到充分研究。目的研究沟槽几何形状对静水压力下铝管动屈曲行为的影响。方法在一个充满水的压力容器装置中进行实验，利用高速成像、3D数字图像相关和压电传感器捕捉圆柱壳的瞬态崩溃行为和相关的局部压力历史。有限元模拟与实验相结合，分析了临界压力对槽壁厚度的敏感性。结果与无槽管相比，中长槽的存在使管道的抗塌能力提高了25% ~ 50%，并降低了峰值动超压。沟槽深度对破坏模式有显著影响，较深的沟槽引起局部屈曲，较浅的沟槽导致整体坍塌。模拟进一步表明，带槽管的抗塌能力提高了65%。结论环形凹槽的引入提高了圆柱壳的抗倒塌能力，其几何形态对破坏模式的决定起关键作用。

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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 Q2 MATERIALS SCIENCE, CHARACTERIZATION & TESTING

Experimental Mechanics

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

S. Baril-Gosselin

Background

Cyclic loading is a leading cause of material failure and accurate testing methods are required to predict the life of components.

Objective

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.

Methods

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 R = - 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.

Results

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.

Conclusions

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.

循环载荷是导致材料失效的主要原因，因此需要精确的测试方法来预测部件的寿命。目的：本研究探讨了进行反向三点弯曲实验表征聚合物和复合材料疲劳寿命的挑战，并寻求制定改进测试方法的指导方针。方法采用聚丙烯（PP）和玻璃纤维增强PP在双面支撑的测试夹具上进行测试。进行单调和完全反向（即应力比R = - 1）循环弯曲实验，以表征测试条件的影响，包括支撑的类型和试件与砧之间的接触水平，对测量结果的影响。结果在反向弯曲过程中产生的应力高度依赖于所使用的夹具配置类型。大多数被测试的结构都会导致机械联锁，从而改变弯矩并产生膜应力。在这项工作中，最纯粹的反向弯曲形式是使用双面旋转支架实现的，样品和砧之间有0.35毫米的间隙，允许在支架中滑动。该配置提供了与标准化简支梁实验中获得的应力状态最相似的状态，用于表征材料的准静态弯曲性能，并且最终是提供最可靠的疲劳数据的配置。

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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 Q2 MATERIALS SCIENCE, CHARACTERIZATION & TESTING

Experimental Mechanics

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

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

Background

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.

Objective

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.

Methods

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.

Results

As-sintered specimens exhibited ductility more than 10 times lower than wrought Ti64, partially due to contamination/impurity that formed brittle (alpha )-case titanium. Sources of contamination may have included the sacrificial Al(_2)O(_3) 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.

Conclusions

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

随着新的增材制造方法的不断发展，增材制造（AM）正在迅速发展。用新方法加工的合金需要系统的表征来理解和验证材料，特别是在要求苛刻的领域。目的研究结合金属沉积法（BMD）制备的Ti-6Al-4V合金的力学性能和失效机理。方法采用Desktop Metal 's Studio System 2对Ti64试样进行打印、脱脂和烧结处理。利用光学金相学和新开发的开源孔隙度分析工具对其微观结构进行了分析。通过扫描电子显微镜（SEM）、光学显微镜以及对绿色、棕色和烧结件的成分分析来研究材料及其失效模式。对烧结试样进行拉伸和硬度测试。结果as -烧结试样的延展性比变形Ti64低10倍以上，部分原因是污染/杂质形成了脆性(alpha ) -case钛。污染源可能包括牺牲的Al (_2) O (_3)中间层、蜡/聚合物粘合剂和/或从炉中引入的杂质。断口成像发现，准解理断裂始于零件沿陶瓷层间表面的高表面粗糙度区域，然后转变为韧窝断裂和晶间脱黏。结论高污染水平、高表面粗糙度和内部孔隙率导致Ti64 BMD合金伸长率和极限强度较低。根据本文提出的工艺路线，Ti64的BMD可能不适合要求高延展性和强度且杂质最少的应用，尽管经过工艺改进，该方法可能对某些应用有希望

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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 Q2 MATERIALS SCIENCE, CHARACTERIZATION & TESTING

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