Magnetic Barkhausen emission measurements for evaluation of material properties in gears

Abstract The magnetic Barkhausen emission (MBE) technique is considered as a potential non-destructive evaluation (NDE) method for assessing material properties in case-hardened gears. For gear manufacturing industries, the evaluation of material properties such as tempering induced changes in hardness level and the associated microstuctural changes, variations in case-depth of hardened layer, grinding process induced alteration in microstructure, hardness and residual stress distributions are of primary importance in order to ensure the quality of gears during service. This paper presents an overview of different research and developmental studies carried out at Design Unit, Newcastle University on the MBE technique suitable for different applications in the evaluation of quality of gears. Keywords: magnetic Barkhausen emissiongear steelstempering heat treatmentcase-depthgrinding damage Acknowledgements The authors acknowledge the interest and support of the British Gear Association and the Ministry of Defence (N), UK. The authors would like to thank David Brown Ltd, UK for heat-treating the samples.