In-Situ Laser Excited Frequency Response of Additive Manufactured Parts
Fielding Additively Manufactured (AM) parts requires evaluating both the part’s geometry and material state. This includes geometry that may be optically hidden. Both the geometry and material state affect the vibration response of the parts and modal analysis (identifying natural frequencies) has been shown to be effective for at least simple geometries using ex-situ methods (shaker table and impact hammer excitations). This paper investigates evaluation of the frequency response of metal parts inside the build chamber using the process laser to excite the parts during printing (Renishaw AM250). Vibrations in the part are measured with accelerometers connected to the build plates and used to track the response during printing as during pauses between layers. The laser is modulated at different frequencies and focused onto specific targets to precisely extract the response from individual parts on the build plate. These results are compared to numerical models for metal parts of different geometries and with different material states.
T. Cullom and N. Altese and D. A. Bristow and R. G. Landers and B. Brown and T. Hartwig and D. Soine and A. Allen and A. Barnard and J. Blough and K. Johnson and E. C. Kinzel, "Frequency Domain Measurements of Melt Pool Recoil Pressure using Modal Analysis and Prospects for In-Situ Non-Destructive Testing," Proceedings of the 30th Annual International Solid Freeform Fabrication Symposium (2019, Austin, TX), pp. 1430 - 1444, University of Texas at Austin, Aug 2019.
30th Annual International Solid Freeform Fabrication Symposium -- An Additive Manufacturing Conference, SFF 2019 (2019: Aug. 12-14, Austin, TX)
Mechanical and Aerospace Engineering
Intelligent Systems Center
Second Research Center/Lab
Center for Research in Energy and Environment (CREE)
Article - Conference proceedings
14 Aug 2019