During thermo-mechanical treatment process of High Strength Low Alley Steel, strengthening is
occurred during finishing deformation due to pre precipitation hardening formed after roughing. Using
HSLA steel containing 0.031% Nb, strengthening of this steel during finishing deformation at temperature
of 900?C under strain of 0.5 is evaluated in terms of stress at 0.05% strain. Data results shows that
the strengthening of this steel due to roughing deformation can be described into empirical model as a
function activation energy (QM) and roughing deformation temperature.
