Ultrasonic testing (UT) - is one of the most widely used nondestructive evaluation methods. A renewed interest in the ultrasonic methods is prompted by the needs of the quality control of additively manufactured products. In additive manufacturing (AM), challenges of the ultrasonic evaluation include considerations of elaborate geometry of AM parts, small size of specimens, coupling issues and complex material compositions. Application of ultrasonic testing in AM promises to improve reliability of printed parts and to reduce the number of printing cycles which, consequently, could reduce the manufacturing costs. In this contribution, the authors suggest an approach to determine the mechanical properties of the additively manufactured dog-bone specimens. Small-scale specimens complied to ASTM standard were fabricated from aluminum alloys. An ultrasonic testing methodology was developed to assess elastic properties of the specimens. Frequencies of the excitation were selected to best match geometrical constraints and address the ultrasonic attenuation. Elastic wave propagation characteristics were measured at various locations yielding spatially distributed properties. A signal analysis algorithm was developed and implemented to extract elastic properties from the ultrasonic data. Conclusions regarding applicability of the developed methodology to additive manufacturing are suggested and future work is discussed.
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