Ultrasound is the gold-standard method to clean stents from a wide range of particle types and sizes. Material interactions during ultrasound arise from ultrasound excitations and imploding cavitation bubbles, however, the exact mechanical impact on the material and component is still unclear. Real-time laser vibrometry and advanced image processing techniques were used to investigate all vibration dynamics during typical process set-ups in a comparison study with different exposure times. Parameters affecting cavitation distribution, energy and ultrasound waves were analysed to quantify correlations between excitation frequencies, cavitation bubble radius and carrier liquid surface tension. Fatigue resistance and radial force measurements were used to evaluate long-term stent performance post-processing.
Discontinuities on the stent surface were identified as preferred sites of bubble formation.  Furthermore, the authors will discuss the mechanical impact and possible damage through resonance from improper choice of ultrasound parameters, stent design, bath dimensions and the cleaning process.