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

Publikationen: Beitrag in FachzeitschriftArtikelForschung(peer-reviewed)

Organisationseinheiten

Externe Organisationseinheiten

  • Erich Schmid Institute of Materials Science of the Austrian Academy of Sciences, Leoben
  • voestalpine Forschungsservicegesellschaft Donawitz GmbH
  • voestalpine Stahl Donawitz GmbH

Abstract

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.

Details

OriginalspracheEnglisch
Aufsatznummer2100065
Seitenumfang9
FachzeitschriftSteel research international
Jahrgang92.2021
Ausgabenummer9
Frühes Online-Datum24 Mär 2021
DOIs
StatusVeröffentlicht - Sep 2021