Laser-directed Energy Deposition (laser-DED) is an additive manufacturing process where a 3D structure is fabricated layer-by-layer with powder that is directed and melted using a high power laser. The processing parameters of laser-DED have a strong influence on the microstructure of the samples that are fabricated. Due to a very high cooling rate, laser-DED produces some unique microstructures like columnar, dendritic grains, and macro-micro grains. The objective of this study is to understand how these microstructures will influence the ultrasonic properties of Inconel 718 (IN718). This work focuses on frequency-dependent parameters such as ultrasonic phase velocity, attenuation coefficient, backscatter and absorption, since they can be related to microstructural features spread over multiple wavelengths: grain size, grain orientation, phases, etc.
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