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Grains induced by dynamic recrystallization are immediately included into the process of forming.
The nuclei that develop mainly at the grain boundaries are still aligned according to the basal character of the old grain [5].
Considering the area of cold forming, other effects such as the insufficient number of slip systems are predominant, which affects the general formability in a negative way.
Due to the previous deformation of structure the nucleus orientation is unlikely to cause a basal texture in the newly formed grains.
After annealing the microstructure in both layers is completely recrystallized with a slight grain growth in the center.

Shear strain [9] (r: distance from the disc centre, N: number of turns, h: thickness of disc), was introduced through rotations for either N = 3, 10, 50 or 120 turns with a rotation speed of 1 rpm.
Vickers microhardness plotted against distance from the disc centre for Al-50%Ni sample processed by HPT for various numbers of turns.
The hardness increased with an increasing number of turns and an increasing distance from the disc centre and saturation of the hardness level at 920 Hv was attained after 50 turns.
This behaviour arises because the magnitude of strain created through HPT increases with increasing the number of turns and the distance from the disc centre.
Twinning, dislocation slip and grain boundary sliding mechanisms appear to be active under compression.

Inclusions which located near the prior austenite grain boundary couldn't induce the nucleation of IAF, only the ones inside the prior austenite grain can promote IAF's growth.
Furthermore, prior austenite grain size is also an important factor affecting the nuclei of IAF [4-5].
Utilizing the intergranular ferrite which had outlined the prior austenite grains, we measured the prior austenite grain size, and the statistic histogram is shown in Fig. 5.
The size of prior austenite grain is about 50~70 micron during the three simulated weld thermal cycles.
The grain size would increase as the phase cooling time extend.

The paper presents an overview of a number of unusual phase transformations which take place in pearlitic steels in conditions of the severe deformation, i.e. combination of high pressure and strong shear strain.
(1) where: R = distance from sample centre, N = number of anvil rotations, h = sample thickness.
The image displays two grains overlapping along the interface.
The right hand grain is <111>oriented ferrite and the left hand one is <110>-oriented austenite, which can be determined from Fourier transforms taken in areas of each grain (Fig. 6a, inserts, Fig. 6b).
Valiev, in: Ultrafine Grained Materials III, (TMS (The Minerals, Metals & Materials Society), 2004 , p. 31) [14] X.

The grains are stretched in the drawing direction.
Measurements and results A number of metallographic studies were carried out which confirmed that after this treatment the wire obtained an ultra-fine grain structure.
But one can see that ferrite grains crush and become smaller (see fig. 3, a).
In some grains the nanostructuring process just begins.
One can see subgrain-grain forming ending at last obtaining of ultrafine grain structure predominantly with largeangle boundaries.

The size of grain is 100 nm.
The grain size was much lager than that deposited at 70 °C.
The crystal grains were larger.
When the number of layers of the films was 15, it was shown in Fig. 4 (c).
When the number of layers is 15, the thickness of the films is 600 nm.

Table 1 Chemical composition of medium-manganese Q&P steel Number C Mn Si P S N Nb Al 7Mn-Nb 0.23 6.93 1.47 0.0062 0.0053 0.0049 0.058 0.0046 The investigated steel was prepared using a laboratory vacuum induction melting process.
The austenite grain nucleation firstly appears in the scope of the original austenite grain, including the boundary of the high carbon high manganese martensite lath and the boundary of slat group and the boundary of the original austenite grain [13].
It is obvious that grains of the investigated steel annealed at 640℃ become equiaxial, and the grain size becomes bigger.
Moreover, it is more obvious that the grains of investigated steel annealed at 660℃ and 680℃ become equiaxial, and grain size becomes maximum
Austenite nucleation position, nucleation number and eventually austenite grain size all depends on the annealing temperature in cold-rolling microstructure.

To detect the defects of cast ingots, a large number of specimens along different orientations of the ingot were prepared after grinding and polishing, and then etched with the saturated picric acid solution for recording the optical micrographs.
Coarse grains primarily consist of columnar and equiaxed grains, as shown in Fig. 1.
(a) columnar grain (b) equiaxed grains Fig. 1 Coarse Grains (a) CaO inclusion (b) FeS inclusion Fig. 2 Non-metallic Inclusions Refining Law of Coarse Grains Effects of Temperature and Deformation on Grain Refinement The average grain size in the primary deformation zone of the specimen was measured after deformation at different experimental conditions, and the grain size grade was also calculated (see Table 1).
The main reason for the tendency can be discovered from the grain growth curve of 30Cr2Ni4MoV steel in Fig. 4 which demonstrates that grain coarsening occurs at about 950˚C, and after that the grain size rises from 40um to 180um rapidly.
Table 1 Average grain size and grain size scale [T—temperature, R—reduction ratio, d—average grain size, G—grain size grade] NO.

Table 1: Required values for the documentation of forging strokes · Timestamp · Number of pass · Number of stroke · Die length · Die radius · Length before/after stroke · Width before/after stroke · Height before/after stroke · Position of the manipulator · Rotation angle of the manipulator · Transportation time to press · Indicator for length measurement · Furnace temperature · Surface temperature The data management in FAST is split into three arrays.
During the cooling process, grain growth takes place, increasing the average austenitic grain size to about 135 µm.
At the faster cooling edges, the resulting grain size is lower.
Fig. 9: Recrystallized microstructure fractions and grain size after the 1st pass of process 1 in the core fibre of the ingot (node number corresponding to position in the workpiece) As the data in FAST is stored for every stroke in the process, a point tracking can easily be extracted from the calculated data.
It can be concluded, that some strokes are influencing the minimum grain size, others do only have a slight influence on the average grain size, which is a result of the low fraction part of the newly recrystallized grains.

As the number of cycle increases, the hysteresis loop transforms to a near linear elastic response.
Such monitoring was carried out for the condition of 100CF at different cycle numbers.
In Fig. 6 (a), the grain boundary offset height measurements vs. the number of cycle are given, showing that offset increases monotonically with cycle number.
The cyclic creep observed was found to increase with the number of cycles, which is associated with the grain rotation. 3.
Crack was verified to nucleate at grain boundaries as the result of severe grain rotation.