Step-by-step surface roughness formation during shot peening and subsequent grinding with flap wheels

Abstract

Shot peening is widely used in forming panels and sheaths. Due to a shot peen impact on a processed surface, a specific microgeometry is formed, a characteristic feature of this microgeometry is the numerous traces of shot (in shape of the dimples) with different diameters and depths. A presence of these dimples causes deterioration of surface roughness parameters. Therefore, after shot peening the mandatory requirement is implementation of surface grinding with flap wheels for partial removal of the dimples. A size of the assigned allowance for grinding depends on the quality requirements of the part surface. At the same time, a depth of the dimples is determined by the part surface roughness requirements. After grinding, the new surface microgeometry as a combination of micro-roughness from previous types of processing and the remaining dimples from impact of shot is formed. In this work the analytical description about formation of microgeometry of surface layer of the samples after shot peen forming and subsequent grinding with flap wheels was presented. The parameters of surface roughness were measured by the method of three-dimensional optical scanning. In the measurement result, the mathematical model of formation of the surface micro-profile during shot peening and grinding with flap wheels was formulated. Keywords-shot peening; grinding with flap wheels; dimple; optical method of three-dimensional scanning; surface roughness during shot peening; surface roughness during grinding with flap wheels I.