Detection of grinding burn through the high and low frequency Barkhausen noise

Abstract

This paper deals with detection of surface damage after grinding through non-destructive micro magnetic technique based on Barkhausen noise. Paper compares the high and low frequency techniques and their sensitivity to detect surface burn and thickness of heat affected zone. The results of investigation indicate that the low frequency technique can more clearly detect surface burn than the high frequency technique due to relatively high thickness of heat affected zones obtained after grinding operations. The paper also discusses additional aspects of micro magnetic testing as a multi parametric technique where such parameters as Peak Position of Barkhausen noise loop correlate with the thermal load of machined surface. The paper also reports about corresponding structure transformations and associated stress state beneath the surface.