Abstract
The plastic deformations processing were realized on material known as high strength low alloyed (HSLA) steel microalloyed by niobium and vanadium. The samples were reheated on 1100°C to dissolution of microalloying element. The plastic deformation process was realized at 950, 1000 and 1050°C deformation temperature, which was the same as annealing temperature. The samples were deformed by 10, 20, 40, 50 and 60 % deformation and annealed for 0, 20, 40, 80 and 100 s. After the annealing the average austenite grains size were determined. At 1000 and 1050°C deformation temperature the fully static recrystallization was observed. At 950°C the samples deformed at 10 and 20 % deformation were fully recrystallized, but the samples at 40, 50 and 60 % shown elongated unrecrystallized grains. The elongated unrecrystallized austenite grains were determinated through effective nucleation area of grain boundary and deformation band. In general, the increasing deformation temperature has shown smaller grain size of austenite and with annealing time the negligible decrease of average AGS can be observed.