Using resonant ultrasound spectroscopy to characterize defects in manufactured metal parts

The ability to nondestructively characterize subsurface defects in manufactured metal parts is not always trivial, especially when it is necessary to inspect parts with varied shapes, sizes, chemical compatibility hazards, or parts that are composed of material with a high atomic number. Resonant ultrasound spectroscopy (RUS) is an attractive nondestructive characterization method because it is low-cost, can evaluate an entire object volume in minutes, and can be applied to objects of different sizes, geometries, and materials with dry-point contact. Here, we report the results for RUS measurements of steel hollow cylinders with millimeter and sub-millimeter drilled hole defects. Improved characterization of hole diameter and location using specific high-frequency resonant modes is investigated with insights provided from finite element modeling results. Preliminary results for RUS measurements of additively manufactured steel hollow cylinders with intentional internal defects will also be shared. [Work supported by the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract No. DE-AC52-07NA27344 and the LLNL-LDRD Program under Project No. 25-ERD-026.]