Magnetic measurements for evaluation of radiation damage on nuclear reactor materials

Nondestructive Magnetic Adaptive Testing of nuclear reactor pressure vessel steel degradation

“…For instance, the observed lower sensitivity of the optimum degradation function of the W material than of the G material, does not necessarily imply lower degradation of the W material with respect to the neutron irradiation. (Actually the direct measurement of the Vickers hardness, HV, of the G and W materials of the investigated samples, which was published in [9] suggest, that modification of this mechanical property by the irradiation was larger in W than in G. Kindly compare figs. 4a and 6a of [9].)…”

“…Even though the materials were thoroughly thermally processed after the rolling (see [9]), some anisotropy of material properties is still evident. The LX-samples, which were magnetized along the direction of rolling, respond magnetically with respect to the neutron irradiation degradation with larger sensitivity than the TX-samples.…”

“…The blocks made from the welding material were not specially oriented. For details about the sample materials and their orientation see [9]. The samples were irradiated by neutrons with energy larger than 1 MeV, with fluences e 0 = 0, e 1 = 1.58 Â 10 19 , e 2 = 2.29 Â 10 19 , e 3 = 9.35 Â 10 19 , and e 4 = 11.9 Â 10 19 n/cm 2 .…”

Nondestructive characterization of flake graphite cast iron by magnetic adaptive testing

“…In all cases a linear correlation was found between the magnetic parameters and hardness [7,11,12,13,19,28]. This coincidence is rather promising from that point of view, that magnetic measurements in general -regardless on the actual type of investigation -reflect the changes in mechanical hardening and in such a way they can replace the destructive and time consuming present standard way of inspection.…”

“…9]. The well known Barkhausen noise effect can also be used for estimation of hardness in cast iron [10][11][12][13]. The so-called 3MA-approach (micromagnetic, multiple-parameter, microstructure, and stress analysis) was developed [14] in the last decade.…”