To determination of removable material during grinding with flap wheels after shot peen forming

Abstract

Shot peening are widely used in forming the long panels and sheaths. Due to impact of shot on the processed surface, the specific microgeometry is formed, the characteristic feature of this microgeometry are the numerous dimples of shot with different diameters and depths. The presence of these dimples causes deterioration of the surface roughness parameters. Therefore, after shot peening the mandatory requirement is implementation of grinding with flap wheels for partial removal of the shot dimples, the depth of which in magnitude significantly exceeds the valleys of micro-irregularities formed as a result of previous treatment. The value of the assigned allowance for grinding depends on the requirements for the quality of the surface of the part. As a result of grinding on the treated surface, a new microrelief is formed in the form of a combination of traces of the impact of abrasive grains of flap wheels and the remains of the dimples from shot peening. At the same time, the depth of dimples of shot after grinding is much reater than the values of valleys of the micro-surface formed as a result of impact of the grains of flap wheels. Since the dimples have a spherical shape with a much larger radius of curvature than their depth, they have a special effect on the volume of the removed metal with an increase in the size of the allowance.