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Non-destructive characterization of 3D printed parts is critical for quality control and adoption of additive manufacturing (AM). The low-cost driver for AM of thermoplastics, typically through material extrusion AM (MEAM), challenges the integration of real-time, operando characterization and control schemes that have been developed for metals. Here, we demonstrate that the surface topology determined from optical profilometry provides information about the mechanical response of the printed part using commercial ABS filaments through calibration based correlations. The influence of layer thickness was examined on the tensile properties of MEAM ABS. Surface topology was converted into amplitude spectra using fast Fourier transforms. The scatter in the tensile strength of the replicate samples was well represented by the differences in the amplitude of the two fundamental waves that describe the periodicity of the printed roads. These results suggest that information about previously printed layers is transferred to subsequent layers that can be resolved from optical profilometry and offers the potential of a rapid, nondestructive post-print characterization for improved quality control.
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Characterization of Additively Manufactured Suspended Finite Ground CPW Interconnects Enhanced by Femtosecond Laser Micromachining
Suspended finite ground coplanar waveguide (FG-CPW) interconnects, fabricated with laser-enhanced direct print additive manufacturing (AM), are modeled and characterized in this work. The study focuses on the variation of characteristic impedance and attenuation with design geometry. Acrylonitrile butadiene styrene (ABS) is printed with fused deposition modeling (FDM) to form 10-mm-long suspended ABS bridges and Dupont CB028 is microdispensed to realize conductive traces on the ABS bridges. Femtosecond pulsed laser machining in the ultraviolet range is combined with the AM to create gaps ranging from 8 to 92 μ m in width on either side of a signal line to define the FG-CPW. Three different suspended interconnects are designed, where the total linewidth (signal line plus gaps) is kept constant at 300 μ m for all designs, but the aspect ratio (AR) (signal linewidth divided by total linewidth) is varied. Two multiline thru–reflect–line calibrations are performed to measure each design: one uses printed calibration standards and the other employs a commercial calibration substrate. The attenuation of the interconnects at 30 GHz is 0.28, 0.13, and 0.06 dB/mm for ARs of 0.95, 0.87, and 0.38, respectively. The laser machining of the gaps results in partial substrate removal, which increases the characteristic impedance by approximately 11%. The impact of fabrication tolerances is examined.
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- PAR ID:
- 10539113
- Publisher / Repository:
- IEEE
- Date Published:
- Journal Name:
- IEEE Transactions on Components, Packaging and Manufacturing Technology
- Volume:
- 14
- Issue:
- 6
- ISSN:
- 2156-3950
- Page Range / eLocation ID:
- 965 to 972
- Subject(s) / Keyword(s):
- 3-D printing, additive manufacturing (AM), aspect ratio (AR), attenuation, characteristic impedance, femtosecond laser, finite ground coplanar waveguide (FG-CPW), machining, suspended interconnect, transmission line (TL)
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
-
Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1109/TCPMT.2024.3399750
