Az. Mohamed et al., MICROSTRUCTURE AND BARKHAUSEN JUMPS IN AN NI-CR EUTECTOID STEEL, Journal of physics. D, Applied physics, 26(9), 1993, pp. 1448-1452
The decomposition of austenite following the initial rapid formation o
f bainitic ferrite in a eutectoid steel containing nominally 1 wt% Ni
and 1 wt% Cr isothermally transformed in the bainitic region of the ti
me-temperature transformation diagram has been studied. The microstruc
ture and kinetics were studied using both optical and electron microsc
opy. Also, the mean potential difference V(B) and the frequency F(B) o
f Barkhausen jumps were measured for various bainitic transformation p
roducts. Lower bainite with fine carbides shows the higher values of F
(B) and V(B). The formation of upper bainite with coarser carbides lea
ds to a considerable decrease of F(B) and V(B), while in the region of
upper bainite and spiky pearlite F(B) and V(B) increase slightly. The
relative amount of the eddy currents depends on the transformation pr
oducts.