The validation of Additively Manufactured (AM) materials is a difficult and expensive process because the local engineering properties are a function of the thermal history. The thermal history varies with the process parameters, as well as the part geometry. This paper presents a case study using modal testing to identify defects in realistic AM parts. A setup consisting of a Scanning Laser Doppler Vibrometer (LDV) was used to identify the resonant frequencies for several geometrically identical parts on a build plate. Parts with suboptimal process parameters from purposely varying the process parameters, are identified by a shift in the mode peak frequency. Results from this study are compared to Finite Element Analysis (FEM) models and generalized for identifying defects in parts created with AM on the basis vibration/modal “fingerprinting.”
J. Urban et al., "Towards Defect Detection in Metal SLM Parts using Modal Analysis "Fingerprinting"," Proceedings of the 28th Annual International Solid Freeform Fabrication Symposium (2017, Austin, TX), pp. 2503-2515, University of Texas at Austin, Aug 2017.
28th Annual International Solid Freeform Fabrication Symposium -- An Additive Manufacturing Conference, SFF 2017 (2017: Aug. 7-9, Austin, TX)
Mechanical and Aerospace Engineering
Intelligent Systems Center
Article - Conference proceedings
09 Aug 2017