Non-Destructive Evaluation of Additively Manufactured Parts via Impedance-Based Measurements

通过基于阻抗的测量对增材制造零件进行无损评估

• 批准号: 1635356
• 负责人: Pablo Tarazaga
• 金额: $ 10万
• 依托单位: Virginia Polytechnic Institute and State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-09-01 至 2020-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1635356&HistoricalAwards=false
• 关键词: Non; Destructive; Evaluation; Additively; Manufactured

There has been a significant increase in the desire to use Additive Manufacturing technologies for the realization of end-use products due to their ability to produce complex geometries that can be tailored to improve system performance. However, broad industrial adoption of Additive Manufacturing has been constrained due to the limitations of currently available non-destructive evaluation technologies, which stymie validation of process performance. To address this need, the research team will explore a non-destructive evaluation technique that uses piezoelectric materials as collocated sensors and actuators to simultaneously excite a printed part and measure its dynamic response. Due to the coupled electromechanical characteristics of piezoelectric materials, the measured electrical impedance depends on the characteristics of the printed part (inertia, stiffness and damping). Therefore, changes induced by printing defects are reflected on the measured electrical impedance, and hence, can readily be detected. This award supports fundamental research to gain an understanding of how part and defect parameters affect the researched non-destructive evaluation process' detection resolution and range. The team has created a well-formulated plan to integrate the central concepts of this research into the summer camp activities offered by Virginia Tech's Center for the Enhancement of Engineering Diversity (CEED). The integration of the research into hands-on laboratory experiences for CEED's underrepresented students will contribute to the development of human resources and seeks to broaden interest in STEM careers related to advanced manufacturing. The primary objectives of this research are (i) to explore how the sensitivity of the impedance-based process is affected by part material and defect type, size, and location, and (ii) to conduct an analysis of the resulting impedance responses to enable identification of defect type. Parts featuring designed defects of various sizes, types (dimensional inaccuracies, positional inaccuracies, and internal porosity), and locations will be fabricated from multiple additive manufacturing processes (polymer extrusion, polymer powder bed fusion, and metal powder bed fusion). The measured impedance-based responses will be compared against baseline responses obtained from defect-free control samples via formulation of the composite damage metric as a multivariable optimization problem, which will enable the team to understand sources of variation in the impedance-based technique's sensitivity. The outcomes of this project include (i) a non-destructive evaluation process for efficiently validating additively manufactured parts and identifying embedded defects; (ii) an understanding of how impedance-based measurements are affected by excitation frequency, part material, and defect topology; (iii) an understanding of how impedance response corresponds to common additive manufacturing defect types; and (iv) a novel composite damage metric and framework for impedance-based defect identification. In this regard, this outcomes of this project will have significant impact on both Additive Manufacturing and Structural Health Monitoring communities.

由于增材制造技术能够生产复杂的几何形状，可以定制以提高系统性能，因此使用增材制造技术实现最终用途产品的愿望显著增加。然而，由于目前可用的无损评估技术的局限性，增材制造的广泛工业应用受到了限制，这阻碍了工艺性能的验证。为了满足这一需求，研究小组将探索一种非破坏性评估技术，该技术使用压电材料作为传感器和致动器，同时激发打印部件并测量其动态响应。由于压电材料的耦合机电特性，测量的电阻抗取决于打印部件的特性（惯性、刚度和阻尼）。因此，印刷缺陷引起的变化反映在测量的电阻抗上，因此，可以很容易地检测到。该奖项支持基础研究，以了解零件和缺陷参数如何影响所研究的无损评估过程的检测分辨率和范围。该团队制定了一个精心制定的计划，将这项研究的核心概念整合到弗吉尼亚理工大学工程多样性增强中心（CEED）提供的夏令营活动中。将研究与实践实验室经验相结合，为CEED代表性不足的学生提供帮助，将有助于人力资源的发展，并寻求扩大对与先进制造业相关的STEM职业的兴趣。本研究的主要目标是：(i)探索基于阻抗的工艺的灵敏度如何受到部件材料和缺陷类型、尺寸和位置的影响，以及（ii）对产生的阻抗响应进行分析，以识别缺陷类型。具有各种尺寸、类型（尺寸不准确、位置不准确和内部孔隙度）和位置的设计缺陷的部件将通过多种增材制造工艺（聚合物挤压、聚合物粉末床熔合和金属粉末床熔合）制造。通过将复合损伤度量公式作为多变量优化问题，将测量到的基于阻抗的响应与从无缺陷控制样本中获得的基线响应进行比较，这将使团队能够了解基于阻抗的技术灵敏度变化的来源。该项目的成果包括：(i)有效验证增材制造零件和识别嵌入缺陷的非破坏性评估过程；（ii）了解基于阻抗的测量如何受到激励频率、部件材料和缺陷拓扑结构的影响；（iii）了解阻抗响应如何对应于常见的增材制造缺陷类型；（iv）一种新的基于阻抗的缺陷识别复合损伤度量和框架。在这方面，该项目的成果将对增材制造和结构健康监测领域产生重大影响。

项目成果

Inexpensive Verification via Electromechanical Impedance for Additively Manufactured Parts

通过增材制造零件的机电阻抗进行廉价验证

• 发表时间: 2018
• 期刊: SAMPE Conference
• 作者: S. M. Strutner, C. Tenney

NDE of Additively Manufactured Parts via Directly Bonded and Mechanically Attached Electromechanical Impedance Sensors

通过直接粘合和机械连接的机电阻抗传感器对增材制造零件进行 NDE

• 发表时间: 2018
• 期刊: IMAC XXXVI A Conference and Exposition on Structural Dynamics,
• 作者: C. Tenney, M. I.

In situ monitoring of material jetting additive manufacturing process via impedance based measurements

• DOI: 10.1016/j.addma.2019.05.022
• 发表时间: 2019-08
• 期刊: Additive Manufacturing
• 影响因子: 11
• 作者: L. Sturm;Mohammed Albakri;P. Tarazaga;C. Williams

Clamping Force Effects on the Performance of Mechanically Attached Piezoelectric Transducers for Impedance-Based NDE

夹紧力对基于阻抗的无损检测的机械连接压电换能器性能的影响

• DOI: 10.1007/978-3-030-12676-6_33
• 发表时间: 2019
• 期刊: IMAC XXXVII A Conference and Exposition on Structural Dynamics
• 作者: Tenney, C.

Traveling Waves As a De-Powdering Process for Additively Manufactured Parts

行波作为增材制造零件的除粉工艺

• DOI: 10.1115/smasis2018-8189
• 发表时间: 2018
• 期刊: Adaptive Structures and Intelligent Systems
• 作者: Tenney, Charles M.;Malladi, Vijaya V.;Musgrave, Patrick F.;Williams, Christopher B.;Tarazaga, Pablo A.
• 通讯作者: Tarazaga, Pablo A.