TY - JOUR

T1 - Influence of Microalloying Elements and Deformation Parameters on the Recrystallization and Precipitation Behavior of Two Low-Alloyed Steels

AU - Monschein, Stefan

AU - Kapp, Marlene

AU - Zügner, Dominik

AU - Fasching, Josef

AU - Landefeld, Andreas

AU - Schnitzer, Ronald

N1 - Publisher Copyright: © 2021 The Authors. Steel Research International published by Wiley-VCH GmbH

PY - 2021/9

Y1 - 2021/9

N2 - The alloy design of modern high-strength low-alloy (HSLA) steels aims for a well-balanced combination of high toughness and strength. Using niobium and titanium as microalloying elements together with thermomechanical processing is a common way to obtain a fine-grained microstructure and therefore enhance the strength and toughness of HSLA steels. Herein, a low-alloyed steel and a microalloyed HSLA steel are investigated in the as-rolled condition and by double-hit experiments using various deformation parameters. Atom probe tomography, scanning transmission electron microscopy inside a scanning electron microscope, transmission kikuchi diffraction, and energy-dispersive X-ray spectroscopy are used to investigate the precipitates in the as-rolled condition and after deformation. It is shown that Nb-enriched TiN precipitates with an average size of around 15 nm are responsible for grain refinement in the as-rolled condition. The annealing temperature prior to the rolling process is set below the solution temperature of Nb(C,N). Enhancing the annealing temperature in the double-hit deformation tests above the solution temperature of Nb(C,N) leads to the precipitation of fine NbC precipitates with a size of around 5 nm. These precipitates are responsible for inhibited static recrystallization behavior.

AB - The alloy design of modern high-strength low-alloy (HSLA) steels aims for a well-balanced combination of high toughness and strength. Using niobium and titanium as microalloying elements together with thermomechanical processing is a common way to obtain a fine-grained microstructure and therefore enhance the strength and toughness of HSLA steels. Herein, a low-alloyed steel and a microalloyed HSLA steel are investigated in the as-rolled condition and by double-hit experiments using various deformation parameters. Atom probe tomography, scanning transmission electron microscopy inside a scanning electron microscope, transmission kikuchi diffraction, and energy-dispersive X-ray spectroscopy are used to investigate the precipitates in the as-rolled condition and after deformation. It is shown that Nb-enriched TiN precipitates with an average size of around 15 nm are responsible for grain refinement in the as-rolled condition. The annealing temperature prior to the rolling process is set below the solution temperature of Nb(C,N). Enhancing the annealing temperature in the double-hit deformation tests above the solution temperature of Nb(C,N) leads to the precipitation of fine NbC precipitates with a size of around 5 nm. These precipitates are responsible for inhibited static recrystallization behavior.

UR - http://www.scopus.com/inward/record.url?scp=85104109700&partnerID=8YFLogxK

U2 - 10.1002/srin.202100065

DO - 10.1002/srin.202100065

M3 - Article

VL - 92.2021

JO - Steel research international

JF - Steel research international

SN - 0177-4832

IS - 9

M1 - 2100065

ER -