Impact velocity and distribution in ultrasonic shot peening
Résumé
We study the dynamic of shot during an ultrasonic shot peening process from two aspects. The first consists in running various calculations of spheres placed in a cylindrical chamber (radius 35 mm, height 40 mm) and propelled by a sonotrode (frequency 20 kHz, amplitude 25 μm). This allows for a better understanding of the minimal peening time needed to reach a stationary regime. The second aspect deals with the relationship between spatial impact distributions and normal impact velocities. Results show that after a specific peening time, initial conditions such as shot position and velocity have no influence on the calculation output. We also found that the surface impact frequency on a peened sample placed on top of a cylindrical or parallelepiped chamber with same inner volumes does not vary much, and that low velocity impacts are mainly concentrated at the edge of the chamber.