Based on magneto-mechanical effect and equivalent theory, the influence of the depth of precut reference defects on stress was evaluated using the metal magnetic memory (MMM) technique. To evaluate a precut defect in the surface of experimental samples, an equivalent technique is used; a three-dimensional electrically controlled displacement system is employed to keep constant the detection parameters for collecting the normal component Hp(y) signal of the experimental sample; the magnetic intensity gradient, corresponding to the location of the precut defect, is extracted based on the least squares technique; and finally, the change on the magnetic intensity gradient as the depths of the precut defects increase is discussed. The results show that the liftoff of the sensor probe is important for the Hp(y) signal, and 1.0 mm is its optimal value. As tensile load increases, the Hp(y) signal turns anticlockwise around a zero-crossing point, and the magnetic intensity gradient changes linearly; when the tensile load reaches the yield load, the change of the magnetic intensity gradient is less obvious as the tensile load increases further. When the tensile load is the same, the magnetic intensity gradient, corresponding to the location of the precut defect, increases as the depth of the defect increases; thus, the influence of defect depth on stress evaluated with the MMM technique can be corrected. Finally, the experimental results are discussed based on the piezomagnetic effect and the model of the finite depth slit, and the change in orientation of the magnetic domains as tensile load increases is seen as the main reason.
ASNT, 2004, Nondestructive Testing Handbook, Vol. 5: Electromagnetic Testing, third edition, The American Society for Nondestructive Testing, Columbus, OH.
Dubov, A.A., 1997, “A Study of Metal Properties Using the Method of Magnetic Memory,” Metal Science and Heat Treatment, Vol. 39, No. 9, 1997, pp. 401–405.
Doubov, A.A., 1996, “The Express-Technique of Welded Joints Examina-tion with Use of Metal Magnetic Memory,” Svaroehnoye Proisvodstvo, No. 11, pp. 33–36
Doubov, A.A., 1998, “Screening of Weld Quality Using the Metal Magnetic Memory,” Welding in the World, Vol. 41, pp. 196–199.
Dong, L.-H., B.-S. Xu, S.-Y. Dong, Q.-Z. Chen, Y.-Y. Wang, L. Zhang, D. Wang, and D.-W. Yin, 2005, “Metal Magnetic Memory Testing for Early Damage Assessment in Ferromagnetic Materials,” Journal of Central South University of Technology, Vol. 12, No. 2, pp. 102–106.
Huang, H., C. Yang, Z. Qian, G. Han, and Z. Liu, 2016, “Magnetic Memory Signals Variation Induced by Applied Magnetic Field and Static Tensile Stress in Ferromagnetic Steel,” Journal of Magnetism and Magnetic Mate-rials, Vol. 416, pp. 213–219.
Leng, Jiancheng, Minqiang Xu, Mingxiu Xu, and Jiazhong Zhang, 2009, “Magnetic Field Variation Induced by Cyclic Bending Stress,” NDT & E International, Vol. 42, No. 5, pp. 410–414.
Leng, J., M. Xu, G. Zhou, and Z. Wu, 2012, “Effect of Initial Remanent States on the Variation of Magnetic Memory Signals,” NDT & E Interna-tional, Vol. 52, pp. 23–27.
Leng, J., Y. Liu, G. Zhou, and Y. Gao, 2013, “Metal Magnetic Memory Signal Response to Plastic Deformation of Low Carbon Steel,” NDT & E International, Vol. 55, pp. 42–46.
Liu, B., W. Miao, S. Dong, and P. He, 2018, “Grain Size Effect on Lcr Elastic Wave for Surface Stress Measurement of Carbon Steel,” Nondestruc-tive Testing and Evaluation, Vol. 33, No. 2, pp. 139–153.
Liu, B., W. Miao, S. Dong, and P. He, 2019a, “Grain Size Correction of Welding Residual Stress Measurement in a Carbon Steel Plate Using the Critical Refraction of Longitudinal Waves,” Research in Nondestructive Eval-uation, Vol. 30, No. 2, pp. 112–126.
Liu, B., L. He, H. Zhang, S. Sfarra, H. Fernandes, S. Perilli, and J. Ren, 2019b, “Quantitative Study of Magnetic Memory Signal Characteristic Affected by External Magnetic Field,” Measurement, Vol. 131,
Liu, C., C. Wang, X. Cheng, Y. Yan, J. Yang, and Y. Guo, 2018a, “Experimental Investigation on the Residual Stresses in a Thick Joint with a Partial Repair Weld Using Multiple-Cut Contour Method,” Materials (Basel), Vol. 11, No. 4, pp. 633–645.
Liu, C., J. Yang, Y. Shi, Q. Fu, Y. Zhao, 2018b, “Modelling of Residual Stresses in a Narrow-Gap Welding of Ultra-Thick Curved Steel Mockup,” Journal of Materials Processing Technology, Vol. 256, pp. 239–246.
Moonesan, M., and M. Kashefi, 2018, “Effect of Sample Initial Magnetic Field on the Metal Magnetic Memory NDT Result,” Journal of Magnetism and Magnetic Materials, Vol. 460, pp. 285–291.
Ni, C., L. Hua, and X. Wang, 2018, “Crack Propagation Analysis and Fatigue Life Prediction for Structural Alloy Steel Based on Metal Magnetic Memory Testing,” Journal of Magnetism and Magnetic Materials, Vol. 462, pp. 144–152.
Ren, S., and X. Ren, 2018, “Studies on Laws of Stress-Magnetization Based on Magnetic Memory Testing Technique,” Journal of Magnetism and Magnetic Materials, Vol. 449, pp. 165–171.
Shi, C.L., S.Y. Dong, B.S. Xu, and P. He, 2010, “Metal Magnetic Memory Effect Caused by Static Tension Load in a Case-Hardened Steel,” Journal of Magnetism and Magnetic Materials, Vol. 322, No. 4, pp. 413–416.
Venkatachalapathi, N., S.MD. Jameel Basha, G. Janardhan Raju, and P. Raghavulu, 2018, “Characterization of Fatigued Steel States with Metal Magnetic Memory Method,” Materials Today: Proceedings, Vol. 5, No. 2, Part 2, pp. 8645–8654.
Xu, M.-X., Z.-H. Chen, and M.-Q. Xu, 2014, “Micro-Mechanism of Metal Magnetic Memory Signal Variation During Fatigue,” International Journal of Minerals, Metallurgy, and Materials, Vol. 21, No. 3, pp. 259–265.
Wang, H.-P., L.-H. Dong, S.-Y. Dong, and B.-S. Xu, 2014, “Fatigue Damage Evaluation by Metal Magnetic Memory Testing,” Journal of Central South University, Vol. 21, No. 1, pp. 65–70.
Wang, Z.D., K. Yao, B. Deng, and K.Q. Ding, 2010a, “Quantitative Study of Metal Magnetic Memory Signal Versus Local Stress Concentration,” NDT & E International, Vol. 43, No. 6, pp. 513–518.
Wang, Z.D., K. Yao, B. Deng, and K.Q. Ding, 2010b, “Theoretical Studies of Metal Magnetic Memory Technique on Magnetic Flux Leakage Signals,” NDT & E International, Vol. 43, No. 4, pp. 354–359.
Wilson, J.W, G.Y. Tian, and S. Barrans, 2007, “Residual Magnetic Field Sensing for Stress Measurement,” Sensors Actuators A: Physical, Vol. 135, No. 2, pp. 381–387.
Yang, L.J., B. Liu, L.J. Chen, and S.W. Gao, 2013, “The Quantitative Interpretation by Measurement Using the Magnetic Memory Method (MMM)-Based on Density Functional Theory,” NDT & E International, Vol. 55, pp. 15–20.
Yin, D.-W., B.-S. Xu, S.-Y. Dong, S.-L. Yang, and L.-H. Dong, 2005, “Characteristics of Magnetic Memory Signals for Medium Carbon Steel under Static Tensile Conditions,” Journal of Central South University of Technology, Vol. 12, No. 2, pp. 107–111.
4 Page Views
0 PDF Downloads
0 Facebook Shares