Visualization of surface waves propagating over surfaces eroded due to particle impact

Abstract

The continuous impact of particles onto a material surface results in erosion. In technical applications particles with a diameter from microns up to millimetres impinge onto surfaces with velocities up to 10 m s −1. In order to investigate experimentally the erosion at the surface of crystalline materials plates of austenitic steel were locally damaged owing to the repeated impact of solid particles. The amplitude of the elastic surface deformation which is excited by the impact of a single particle is only 10 −9-10 −7 m. The surface deformation which is caused by such an impact was measured by means of double-pulse holographic interferometry. Because of the small amplitude of the surface waves quasi-heterodyne holographic interferometry was required. The areas of initial wear of the materials can be recognized by the disturbed propagation of the surface waves.