Abstract Scope |
As additive manufacturing continues to mature and advance, the technology is being used in increasingly complex and critical applications. In these applications, advanced qualification activities, including full-scale testing with high-fidelity sensors, are needed to obtain critical insights into the behavior of the printed material. For this work, an exemplar test article was printed using wire arc additive manufacturing (WAAM) and subjected to an array of advanced qualification techniques. After printing, the part was 3D scanned for comparison of the as-built geometry to pre-build CAD modeling. The distortion resulting from printing is presented and compared to a pre-build computational distortion simulation. A Finite Element Model (FEM) was created and a Finite Element Analysis (FEA) comparison between the idealized (to be printed CAD model) geometry and the actual scanned geometry was conducted. After printing, the part was inspected with wet fluorescent magnetic particle testing and liquid dye penetrant. The part was then subjected to full scale testing and monitored with acoustic emission sensors to listen for crack growth. Loading was cycled to analyze the acoustic signature of crack growth in the 3D printed material. During pressure testing, the part was also monitored with a Digital Image Correlation (DIC) system to capture strain distribution and response in the material. This strain distribution was then compared to the FEM strain prediction and the difference interrogated. Mechanical tensile tests were conducted using witness coupons that were printed alongside the actual part for comparison to material removed from the printed part. A metallographic examination was conducted on the as-printed material in order to characterize the microstructure. The results of this testing are presented to give an example of high-fidelity qualification program attributes and resulting outcomes. This paper shows how analytical, empirical, and material characterization methods can be combined to qualify AM parts for critical applications. |