Residual stress analysis of additive manufacturing of metallic parts using ultrasonic waves: State of the art review

Additive manufacturing has become a major growing field in materials engineering, following a new tendency for custom, high precision and on-demand fabrication. Residual stresses are prone to appear in any production technique, which remain a challenge to be measured. These stresses can lead to a reduction on mechanical performance and even cause premature failure. Thus, a wide understanding of residual stress is critical for greater part reliability. Among Non-destructive Testing (NDT) techniques, acoustic and ultrasonic waves remain widely used to determine stresses, voids and defects in a wide array of parts. In this contribution, Ultrasonic Testing (UT) is highlighted as an alternative for measuring residual stress both during and after fabrication.