Title :
Nondestructive evaluation of aged 1Cr-1Mo-0.25V steel using first harmonics
Author :
Ryu, K.S. ; Park, J.S. ; Nahm, S.H. ; Yu, K.M. ; Kim, Y.B. ; Son, D.
Author_Institution :
Korea Res. Inst. of Stand. & Sci., Taejon, South Korea
Abstract :
We present a new procedure to evaluate the first harmonics in a 1Cr-1Mo-0.25V steel. The method is based on the existence of the first harmonics in the differential magnetization around the coercive force. The apparatus is based on the detection of the voltage induced in a coil using a lock-in amplifier tuned to a frequency close to the exciting one. Results obtained for the first harmonics and Vickers hardness on the annealed samples, show the peak width of the first harmonics and Vickers hardness decreased as aging time increased. The correlation between Vickers hardness and the peak width of the first harmonics could be evaluated nondestructively.
Keywords :
Vickers hardness; aging; alloy steel; coercive force; ferromagnetic materials; harmonics; nondestructive testing; Vickers hardness; aged steel; aging time; coercive force; differential magnetization; domain wall pinning; first harmonics; induced voltage detection; lock-in amplifier; microstructure; nondestructive evaluation; peak width; Aging; Amplifiers; Coils; Frequency; Inductors; Magnetic materials; Magnetization; Steel; Turbines; Voltage;
Conference_Titel :
Precision Electromagnetic Measurements Digest, 2000 Conference on
Conference_Location :
Sydney, NSW, Australia
Print_ISBN :
0-7803-5744-2
DOI :
10.1109/CPEM.2000.850967
