text: The HiFIT hammer operates with a hardened pin with a ball resting on the workpiece with a diameter D of 3 mm.
  This pin is hammered with an adjustable intensity at around 180–300 Hz at the weld toe. Local mechanical deformations occur in the form of a treatment track. The weld toe is deformed plastically. The induced compressive residual stress prevents the track cracking and the crack propagation on the surface.