Ganwarich Pluphrach

pp. 409 - 413

Abstract

Micro-Alloyed rolling steels with low carbon content were hot deformed followed by direct cooling of blowed-air in
two processes and additional annealing at relatively low temperatures. Effective yield strength was controlled by applying
different mean grain size conditionings using Hall-Petch equation. It was shown that increasing the vanadium alloying element
content increased the yield strength and also decreased the mean grain size. The development of the complex as-casted
polygonal-acicular ferrite / pearlite microstructures during the cooling and annealing treatment was systematically investigated and correlated with yield strength.