258 Prakt. Met. Sonderband 46 (2014)
For thickness reductions greater than 15%, the results suggested the formation of the EINFL
ferromagnetic Strain-Induced Martensitic phase (SIM) from austenite, especially in the low- DAS F
alloyed SAF 2101 and 2304 grades (Lean DSS). The metallographic observations on the
Beraha’s etched samples underlined the occurrence of microstructural modifications inside UND I
austenite, which tended to expand inside the austenitic grains as the deformation degree
was increased. The same features were less observed in SAF 2205 and were instead H. Rojac
absent in SAF 2507, the higher-alloyed DSS. However, these regions cannot be strictly
related to SIM, but the other performed investigations confirm in some extent the presence ACT res
of the new phase.
The magnetic measurements in Lean DSS revealed a strong increase in magnetic phase,
ascribable to SIM formation; this was also observed in SAF 2205, but in a significantly ZUSAN
lower extent, whereas no changes in magnetic properties was registered in SAF 2507.
However, where SIM formation seemed to take place, cold rolling did not cause the total Verschle
transformation of the austenitic phase, since XRD revealed the presence of y-peaks at any Tempers
deformation degree. Diese A
The results confirmed a more proneness to microstructural modifications induced by rolling mechani
in Lean DSS, whereas cold working did not substantially alter the steels properties in the wurde by
higher-alloyed grades, owing to the increased austenite stability. In a recently published tests bis
work [9], the effects of cold rolling on DSS pitting resistance have been presented, Belastur
confirming the greater stability of 2205 and 2507, even after severe plastic deformation, Um ver.
and denoting the great loss in corrosion properties affecting cold rolled Lean DSS. wurden,
Compos
Oberflac
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iel dies
N ; 5 . . die Ver
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