Fig. 11 shows the formation of ferrite (white regions) and pearlite
(dark areas). As the austenitizing temperature increases, the
free ferrite formation adopts morphology acicular or needleshaped
(Fig. 11c) that penetrates into the pearlite colonies.
According to [17] this acicular ferrite texture is generally associated
with an increase in grain size (probably due to increasing in
austenitizing temperature)