Detalle Publicación


Microalloying additions to commodity C-Mn structural steels: fundamental strengthening mechanisms leading to improvements in mechanical properties, alloy optimization, reduced alloy costs robustness of hot rolling processing

Autores: Barbosa, R.; Uranga Zuaznabar, Pedro; Rodríguez Ibabe, José María; Stahlheim, D.; Rebellato, M. (Autor de correspondencia); Qiao, M.; Wang, H.
Título de la revista: MATERIALS SCIENCE FORUM
ISSN: 0255-5476
Volumen: 941
Páginas: 71 - 76
Fecha de publicación: 2018
Niobium in steels can be used as substitutional solid solute or as precipitates. In solution, Nb exerts a solute drag effect delaying but usually not interrupting static recrystallization during hot rolling and increasing hardenability during post rolling cooling. Fine precipitates generated during rolling/cooling can interrupt recrystallization in finishing and precipitate in the ferrite matrix increasing strength. As a relatively fine precipitate Nb can also inhibit austenite grain growth during reheating.This paper highlights the idea that micro-additions of Nb, up to 0.02%, to ordinary commodity C-Mn structural steels can improve their strength. Industry trial results are presented giving evidence that mechanical properties can be improved, and a leaner/optimized chemistry may be used by adding these micro-quantities of Nb to otherwise ordinary commodity C-Mn steels.Microstructural analysis of a C-Mn vs. a leaner/optimized C-Mn-micro Nb steel along with austenite evolution modeling using MicroSim-PM© helped identifying which type of metallurgical mechanisms are in-play resulting in higher strengths. This alternative composition has led to lower costs, lower CE, improved microstructure and a more stable process.