3Kashiwaya K, Sakamoto H, Inoue Y. Residual stress measurement of induction hardened axle using magnetic sensor[ J. Journal of NDI ( in Japanese) , 1987,36 ( 12 ) : 894 - 900.
7Haishun Liu, Chaochao Dun, Linming Dou, Weiming ang. Theoreti- cal analysis of magnetic senor output voltage [ J]. Journal of Magnet- ism and Materials ,2011 ( 323 ) : 1667 - 1670.