Pole tekstowe: THE STRUCTURE AND MECHANICAL PROPERTIES OF LOW CARBON
LOW ALLOY STEEL SUBJECTED TO SEVERE PLASTIC DEFORMATION A. V.
Korznikov, Institute for Metals Superplasticity Problems, RAS
Khalturin 39, 450001 Ufa, Russia, Z. Pakiela, K.J. Kurzydlowski,
Faculty of Material Sciences and Engineering, Warsaw University of
Technology, Woloska 141, 02-507, Warsaw, Poland The steel (C-0.03wt.%,
Mn-1.38%, V-0.25%) was deformed using a multi-high mill; the rolling
was carried out by a quarto mill for 10 passes with a total reduction
of 95% in the temperature range 950 -500C. Such a treatment allows to
produce submicrocrystalline (SMC) structure with the mean grain size
about 0.7 mm; this is due to fragmentation and recrystallization. The
formation of SMC structure leads to the increase of the strength
properties. The yield stress of the SMC steel is of two or three times
higher than that after the hot deformation; s0,2 is 935 MPa, su is 945
MPa; the decrease of plasticity is virtually negligible. The toughness
at low temperature (77K) increased more than ten times in comparison
with that in a coarse grained state.
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