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In non-lubricated rolling, the grain quantity of misorientation 0°～10° accounted for 9.8%, but the grain quantity of misorientation 0°～10° accounted for 29.7% in lubricated rolling, the grain quantity of misorientation 0°～10° on surface lubricated rolling 3 times higher than non-lubricated rolling, the proportion of small-angle grain boundaries significantly increased.
In non-lubricated rolling, the grain quantity of misorientation 0°～15° accounted for 14.4%, but the grain quantity of misorientation 0°～15° accounted for 36.3% in lubricated rolling, the grain quantity of misorientation 0°～15° on surface lubricated rolling 2.5 times higher than non-lubricated rolling.
Misorientation of slip systems of adjacent grain caused resistance to dislocation motion mainly, high angle grain boundaries more effectively prevented the dislocations movement[3].
This shows that misorientation between grains decreases.
Acknowledgment Funded projects provided by State Key Laboratory (northeastern university) ,serial number:2009004.

Introduction As is noted in [1], there are a number of hard to explain anomalies that do not correspond to the classical model of Cottrell's "atmospheres" in FeAl.
At the same time, they noted the presence of a number of hard to explain anomalies that do not correspond to the classical model of Cottrell's "atmospheres".
In this connection, the authors of [1] also noted other similar results for boron segregations at <100> edge dislocations, (001) packing defects, grain boundaries and antiphase boundaries in the same intermetallic compound.
From the data presented in Fig. 3, one can estimate the number (nB┴ ≤ 1) of boron atoms (more precisely, the "complexes" of Fe3B) per dislocation of the atomic length (that is, one plane (100) perpendicular to the <100> edge dislocation).
On the carbon kinetics in martensite, relevance to nanosegregation at dislocations and grain boundaries. 30 (2017), (http://diffusion.uni-leipzig.de/contents_vol30.php)

Flow stress of grain.
Fig. 1 shows surface/outer grains and volume/inner grains.
The size effect factor is defined as the ratio of surface grains to total grains in the section as follows: (3) is the size effect factor, and are the numbers of surface and total grains in the section, respectively.
The resultant flow stress of the material can be expressed as follows: (4) is the number of volume grains.
The number of surface grains in the section can be calculated as follows: (8) , , and are specimen width, sheet thickness, and grain size, respectively.

The microstructural reactions resulting in hydrogen incorporation significantly decrease the number of cycles to failure of the specimen.
A negative applied potential increases the number of cycles to failure.
Horizontal grain degradation primarily occurs within the austenitic phase, leaving the ferritic phase unaffected [13,14] most likely because the γ-phase reveals a lower corrosion resistance according to PREN (pitting resistant equivalent number) [15].
The impact of hydrogen on the number of cycles to failure was compared to results from fatigue specimens at a distinct cathodic potential (USHE = -36 mV).
Crack propagation can be described as horizontal corrosion within grains and along grain boundaries beneath the subsurface zone.

The pro-eutectoid ferrite prefers to form at the austenite grain boundaries and selects the variant according to the relative orientation of the austenite grains on the two sides [1].
The bainite prefers to nucleate at the grain boundary as well.
In the steels with very low carbon, however, the grain boundaries are usually occupied by the allotriomorphic ferrite formed before the bainite transformation.
EBSD analysis is carried out to measure the orientation of bainite in one prior austenite grain. {001} poles of bainite in one prior austenite is shown in Fig.2.
The variant analysis shows that those ferrites maintain near K-S orientation relationship with the prior austenite grain on this side.

Abnormal oxidation behaviour is more clearly recognized around the grain boundaries, in which γ Figure 2.
Fig. 5a-c show the oxides formed on the three steels after a period of 24 hours at 1000ºC and from here a number of interesting differences emerge.
The grain size of the outer oxides is typically in the region of 1-2 µm in comparison with the somewhat finer grained inner layer, 0.4-1 µm, which is largely consistent with the mechanisms of their formation.
Immediately above and to the sides of the metal, coarse grains of Cr2O3 were found and the grain marked at C had a composition of some 92.5 at%Cr, 4.1 at%Fe and 1.8 at%Mn as given in table 4.
The glassy phase was also found to contain a number of crystalline precipitaes, as indicated by localized agglomerates that can be seen in the higher magnification bright field image shown in Fig. 7b.

The Hall-Petch equation describes the yield strength σ y based on grain size: σy=σ0+kd-0.5 (5) where σ0 is the intrinsic yield strength of the material, k is the Hall-Petch coefficient, d is the grain size.
Edge detection methods like Sobel and Canny filters can be applied to enhance grain boundary visibility.
The accuracy of microstructure classification depends on the training process, including the number of epochs, learning rate, and batch size.
Research of CNN Train Model To ensure robust classification, authors preprocess images using OpenCV and NumPy to enhance grain contrast and suppress noise.
The implemented script processes microstructure images through hierarchical feature extraction layers, capturing grain morphology, contrast variations, and phase boundaries.

The basis of this method is to indent and drive free abrasive grains on the wheel surface in order to excavate the binder material between the CBN grains and uncoated the exposed portion of the grains.
Above Results and Discussion In generally, dressing was the processing for the worn grains on the surface of grinding wheels to producing sharp new edge on the grains to cut more effectively.
Fig. 2 shows material removal for different CBN grain concentrations.
This is because more grains are available to cut the workpiece simultaneously.
An increase of CBN concentration can increase the material hardness of the specimens and reduce the number of specimens consumed.

They lower the flow stress and modify microstructural parameters such as grain size [3, 4].
(7) Assuming that the nucleation of grains due to DRX occurs at the grain boundaries only [9], 2A C S= (8) where 2C is a constant and S is the grain boundary area per unit volume.
(10) gbM can be expressed as [9] ( )2, gb gb m M D V b RT δ= (11) Fig. 1 Grain morphology. where δ is the grain boundary thickness, gbD is the grain boundary self diffusion coefficient, mV is the molar volume of the recrystallized grains and R is the gas constant.
Reported values for the grain boundary self diffusion coefficient (equation (11)) are expressed by an Arrhenius law ( )0exp , gb gb gb D D U RT δ δ= − (30) where 0gbD is a pre-exponential factor and gbU is the activation energy for grain boundary diffusion.
The grain size d is 200 µm and 340 µm for Ni and Cu, respectively. h is assumed to be equal to d (Fig. 1).

Due to the status of base metal was rolled, grain was very unstable, and grain would grow up sharply after heated, and making grain of HAZ was the most coarse grains.
Large heat input further promoted the grain coarsening, results in coarse grain associated with the degradation of joint’ properties.
The grain of weld zone was fine, and was a typical casting quench tissue.
The grain of HAZ was the most coarse grains associated with the degradation of joint’ properties.
The grain of weld zone was fine and that was a typical casting quench tissue