TITLE:
Structural Evolution and Properties of Hot Rolled Steel Alloys
AUTHORS:
Emmanuel Isaac Akpan, Idoko Andrew Haruna
KEYWORDS:
Recrystallization, Microstructure, Zener Hollomon Parameter, Deformation, Rolling, mild steel
JOURNAL NAME:
Journal of Minerals and Materials Characterization and Engineering,
Vol.11 No.4,
April
20,
2012
ABSTRACT: Microstructural evolution during hot rolling of mild steel (0.3%C) has been considered to determine its relationship with the mechanical properties. Strain, strain rate, temperature and Zener Hollomon parameter were considered as structural parameters. Deformation parameters were collected industrially and the Zener Hollomon parameter calculated from the formula;Z=e exp(Q/RT). Microstructural features considered were grain size, inclusions, distribution of phases and banding. The grain size was calculated using the ASTM grain size number and the fraction distribution of phases was determined using a 10×10 grid counting. Mechanical properties considered were ductility, tensile strength, hardness and yield strength determined by laboratory experiments. Grain size was found to be inversely related to the Zener Hollomon parameter. Strength (Tensile, Yield and Fracture) were found to be inversely related to grain size but directly related to fraction distribution of phases. Banded structure and inclusions were found to be detrimental to strength and ductility.