ASSESSMENT OF MICROSTRUCTURE IN 42CrMo STEEL BY BARKHAUSEN NOISE ANALYSIS

摘要

The different microstructure will result in different structure of magnetic domains and motion of domain wall. Barkhausen noise(BN) will change with different microstructure. we can use BN analysis method to assess microstructure of ferrite-magnetic material. The relation between microstructure and intensity of BN in 42CrMo steel has been studied. With different heat treatment condition, microstructure is different. Hardness is a characterization parameter to indicate microstructure. The BN has been measured by using magnetic-elastic equipment. The relation between hardness and intensity of BN has been obtained. The result shows that BN analysis method is a better nondestructive testing method for assessment microstructure.