Article Article
Experimental Nondestructive Characterization of an Aluminum Alloy Prepared by Powder-Bed Additive Manufacturing

Additive manufacturing (AM) has a number of potential advantages for fabrication of metallic components for aerospace and other high-reliability applications. Nondestructive evaluation and inspection techniques will be needed to achieve the levels of quality assurance that have been successful for fabrication using traditional means. AM has developed rapidly in recent years, and published descriptions of nondestructive evaluation (NDE) techniques applied to AM materials have begun to emerge. In the present work, we investigate the microstructure, elastic properties, and discontinuity population of an aluminum alloy prepared by selective laser melting using ultra-sonic measurements and computed tomography (CT) radiography. The elastic properties were compared between samples with different thermal histories and different sizes, and showed small but meaningful differences due to direction within the sample and heat treatment. X-ray CT was used to qualitatively and quantitatively describe the discontinuity population, which was influenced by both laser settings and scanning strategies. The results of NDE can be used for process optimiza-tion, design, and stress analysis.


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