Prakt. Met. Sonderband 46 (2014) 91 
and consequently tester. The principle scheme of deformation generation by ball of hardness tester machine 
ties, NO steels are is show in Fig. 1c. 
is is to develop a The heat treatment was realized with furnace “Nabertherm” equipped with an electronic 
size of processed control system C19/S19. The microstructure of the investigated specimens was examined 
ased at elevated in cross section plane parallel to rolling direction. An average grain size in the chosen 
texture state as a microstructural states was estimated by means of metallographic analysis software. On 
the other hand this software allows get visible the grain boundary. The texture local 
igated in this work. misorientation map of laboratory treated samples was measured in the same section by 
is well know, that means of EBSD method. The JEOL JSM 7000F FEG scanning electron microscope was 
form [4]: employed to perform the texture analysis. Patterns formed from back scattered electrons 
were detected by “Nordlys-1” EBSD detector. The obtained EBSD data were analyzed and 
displayed by CHANNEL-5, HKL software package. 
b the dislocation 
nnealing plays an 
dient deformation 3. RESULTS AND DISCUSSION 
> sample. 
The outgoing microstructure of the investigated F1A steel, taken after primary 
recrystallization at 800°C for 10 min in dry hydrogen atmosphere, is shown in Fig. 2. As 
one can see. the F1A material possesses a quite fine-grained microstructure with mean 
grain size 20-25um. 
tent was used as Fig. 3 present three different types of microstructure 
al cold rolling with obtained after heat treatment in the sample with uniform 
\ at 800°C for 10 gradient deformation. The dependence of dynamic of 
omposition of the grain boundary motion on applied deformation gradient 
; ; } value is presented in the Fig.3 from left to right. The Fig. 
sformation through Fig. 2 Material F1A after 3a hows the microstructure of the investigated steel 
mation were used. primary recrystallization at _ . Co : 
800°C/10 min. with the mean grain size of ~ 30-40 um. The mentioned 
_. — - grain size was observed in the investigated samples at 
Al, Cu, the region without deformation. The next picture 
% % _ represents the samples area with applied deformation around 3%, see Fig. 3b. This picture 
0.025 0.06 is taken at the middle of the samples with the uniform gradient deformation. As one can 
he whole length of see, the fraction of small grains (with grain size ~ 40 um) is about 70% of the total area of 
» to 6%, hence the grains. The grain size of the huge grains is about 300 um. The fraction of this grain is 
. This deformation about 30% of the total area of grains. Almost all the huge grains are located near the 
ase, the stepwise 
ion was performed 
- step deformation 
ne in 4%, see Fig. 
it loads made by a, nn 
‘ Fig. 3 Sample F1A of the investigated steel with uniform deformation gradient after 
= annealing at the temperature 900°C for 300 sec.: sample area a) with deformation 
= ; £~0%, b) with £~3% deformation, ¢) with £ ~6% deformation. 
Te N surface of the sheet plane, see Fig. 3b. The mentioned grain growth features leads one to 
suggestion of abnormal grain growth character of grains located near the surface of the 
steel sheet. The Fig. 3c represents the microstructure of the samples area with the 
olume of samples. maximum deformation £~6%. As one can see, almost all grains are huge with the mean 
rated deformations grain size of 500-600um. The mentioned grains have grown through the whole thickness 
ies were controlled of the investigated steel sheet. These facts leads one to conclusion that application of 
all of the hardness particular deformation to the samples with combination of heat treatment leads to