Resonant Ultrasound Spectroscopy Modeling of Hybrid Metal Additive Manufacturing 316-L Stainless Steel

Jazmin Ley, University of Nebraska-Lincoln

Photo of Jazmin Ley

Hybrid additive manufacturing (AM) involves secondary processes or energy sources to alter specified locations within the build. Each hybrid step can refine the grain size, increase dislocation density, or modify residual stresses. Typically, the changes in mechanical properties are not confined within a single layer but have a compounding effect on preceding layers. Control of properties within a build can enhance component performance but unique challenges remain for nondestructive validation of such samples. Traditional ultrasonic methods on hybrid-AM components have successfully mapped material variations with sufficient spatial resolution. However, the use of resonance ultrasound spectroscopy (RUS) for hybrid-AM is less developed. In this paper, finite element models are used to examine the sensitivity of RUS measurements in terms of frequency shifts and mode shapes with respect to specific layers of residual stresses. The RUS model provides new insights for experimental results from hybrid-AM samples of stainless steel with hybrid layers.