Nondestructive test methods have focused on specific and narrow properties of critical dimension, hardness, visual indications, or localized crack detection, while missing significant structural characteristics not apparent without destructive test.
Multi-frequency resonant inspection is a new technology, which accomplishes a quantitative, whole-body, structural analysis using natural mechanical resonances of a powder metal part. The technology is applicable to a wide range of product size and geometries, and has been used successfully on powder metal connecting rods, timing gears, ABS rings, exhaust flanges, gerotors, and more.
This paper describes measurement and application fundamentals in context of a connecting rod study on production parts. Data is presented which demonstrate the ability to detect structural defects in sintered powder metal parts.