Pattern formation and waviness in surface grinding

Abstract

Surface ground workpieces can exhibit quality impairments in the shape of unwanted pattern formation. Experimental investigations show, that pattern formation in surface grinding is independent of self excited vibration and that the pattern wave length coincides with the tangential feed. The observed patterns can therefore be attributed to e. g. either residual grinding wheel imbalance, roundness error or non-uniform grinding wheel surface topography. The visibility of the patterns mainly depends on the magnitude of the tangential feed. Increasing the feed reduces pattern visibility. Due to the underlying formation mechanism, pattern formation goes hand in hand with a waviness profile, which is dominated by waves with a wavelength equal to the pattern wave length. By measuring and adjusting the phase shift between the grinding wheel rotation during consecutive grinding passes, both the workpiece waviness and the visibility of the surface patterns can be reduced during sparking out.