Influence of residual stress and texture on the resonances of polycrystalline metals

Efficient nondestructive qualification of additively manufactured (AM) metallic parts is vital for the current and future adoption of AM parts throughout several industries. Resonant ultrasound spectroscopy (RUS) is a promising method for the qualification and characterization of AM parts. Although the adoption of RUS in this setting is emerging, the influence of residual stress and texture, which are both very common in AM parts, is not well understood. In this article, a stress- and texture-dependent constitutive relation is used to study the influence on free vibrational behavior in a RUS setting. The results that follow from using the Rayleigh-Ritz method and finite element analysis suggest that residual stress and texture have a significant impact on the resonance frequencies and mode shapes. These results support the potential of using RUS to sense texture and residual stress in AM parts. Additionally, these results suggest that RUS measurements could be misinterpreted when the stress and texture are not accounted for, which could lead to a false positive/negative diagnosis when qualifying AM parts.