Using BB-Gun or Acoustic Excitation to Find High Frequency Modes in Additively Manufactured Parts
Additive manufacturing (AM) considers parts that are produced at a low volume or with complex geometries. Identifying internal defects on these parts is difficult as current testing techniques are not optimized for AM processes. The resonant frequency method can be used to find defects in AM parts as an alternative to X-ray or CT scanning. Higher frequency modes at approximately 8000 Hz and above cannot be tested with a traditional modal hammer or shaker since they do not provide enough excitation. The goal of this paper is to evaluate creative testing techniques to find internal defects in parts with high frequency modes. The two types of testing methods considered are acoustic excitation provided by two speakers and high velocity impact testing produced by a BB - gun. Although the frequency ranges of interest are part dependent, these techniques were able to reach up to 16,000 Hz, which is an additional 8000 Hz above what the traditional modal hammer is able to reach. This work was funded by the Department of Energy’s Kansas City National Security Campus which is operated and managed by Honeywell Federal Manufacturing Technologies, LLC under contract number DE-NA0002839.
A. Allen and K. Johnson and J. R. Blough and A. Barnard and T. Hartwig and B. Brown and D. Soine and T. Cullom and D. A. Bristow and R. G. Landers and E. C. Kinzel, "Using BB-Gun or Acoustic Excitation to Find High Frequency Modes in Additively Manufactured Parts," Conference Proceedings of the Society for Experimental Mechanics Series, pp. 77-84, Springer, Sep 2020.
The definitive version is available at https://doi.org/10.1007/978-3-030-47713-4_9
Society for Experimental Mechanics Series
Mechanical and Aerospace Engineering
Keywords and Phrases
Additive manufacturing; Excitation; High frequency; Internal defect; NDT
International Standard Book Number (ISBN)
International Standard Serial Number (ISSN)
Article - Conference proceedings
© 2020 The Society for Experimental Mechanics, Inc., All rights reserved.
30 Sep 2020