<p>Electromechanical impedance measurements allow for a quick assessment of the mechanical integrity of the part under test by providing insights into its dynamic response. In previous studies, it has been shown that electromechanical impedance signatures obtained via directly bonded piezoelectric transducers can successfully be used for non-destructive evaluation of manufactured parts. Indirect electromechanical impedance measurements, through an instrumented fixture or testbed, has also been introduced as a promising solution for a quick evaluation of manufactured parts. While such indirect impedance measurements alleviate the need for individual parts to be instrumented, they increase the complexity of the measurement system. Factors such as fixture design, part-fixture interface, and clamping force are found to impact measurement sensitivity to manufacturing defects and anomalies.</p><p>In this paper, the effects of instrumented fixture material on indirect electromechanical impedance measurements are investigated. Two geometrically-identical fixtures are used in this study. The first is a commercially available clamp made of steel, while the second is an additively manufactured replica made of polymer through a material jetting process. Both fixtures are instrumented with macro-fiber composite piezoelectric transducers for electromechanical impedance measurement. Strain gauges are also used to measure the clamping force exerted by the fixture on the part under test and ensure its consistency. Test specimens are made of machined steel blocks including defect-free (control) parts along with others featuring manufacturing defects. The impact of the fixture’s material properties, as compared to the part under test, on the defect-detection capabilities of indirect impedance-based NDE is evaluated.</p>

Indirect Impedance-Based NDE Through Instrumented Fixtures; Effects of Fixture Material on Defect-Detection Capabilities

Paper Proceedings: https://asmedigitalcollection.asme.org/SMASIS/SMASIS2021/volume/85499

ASME 2021 Smart Materials, Adaptive Structures and Intelligent Systems (SMASIS2021)

Supporting the need among researchers worldwide for additional online and multimedia content, ASME now offers the ASME Conference Video Collection. This platform will collect and provide long-term access to conference presentation videos, encompassing all technology areas within ASME's technical conference and events program. About 30,000-40,000 engineers across all mechanical engineering and related disciplines participate in ASME conferences each year. This includes authors of approximately 6,000 to 8,000 technical papers published by ASME, the majority of whom also submit video presentations for our virtual conferences. The video collection will be available as an add-on to existing product packages or as a separate subscription.