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A number of these particles show co-precipitates and contain Nb suggesting that NbC co-precipitates at TiN.
Further, a number of Mo-rich particles were observed with a size of approximately 100 nm.
At least 400 grains were measured to quantify the mean EQAD.
These larger grain sizes indicate appreciable grain growth during heating at a rate of 10 °C/s rather than during the brief holding at peak temperature.
The promotion of grain growth above 1150 °C may be related to dissolution of NbC even though no indication of abnormal grain growth was observed.

In more recent years, the culmination of a number of substantial worldwide research programmes have shown that realisation of a submicron (<1µm) grain size is now achievable through hot rolling.
%C steel with increase in ECAE deformation 0 1 2 3 4 0 1 2 3 4 Strain (von Mises) Boundary Spacing (µm) 0 20 40 60 80 100 0 1 2 3 4 5 6 Number of ECAE passes Percentage HAGB (%) Grain Width % HAGB 0 200 400 600 800 1000 1200 1400 0 1 2 3 4 5 Number of ECAE passes Tensile Strength (MPa) 0 5 10 15 20 25 30 35 Elongation (%) 0.2%PS (MPa) UTS ElongationSummary Efforts to produce a two-phase ultra-fine grained structure in high carbon (0.6-1.2wt.%) steels through innovative deformation have proved successful.
Slow grain refinement observed in the 0.6wt.
Dong: Ultra-fine Grained Steels and Properties, International Symposium on Ultrafine Grained Steels (2001), p. 18
Miller: The Ductility of Ultrafine Grained Alloys, Ultrafine-Grain Metals, J.J.

Their maximum grain diagonal size, minimum grain diagonal size, and average grain diagonal size are 90 μm, 11 μm, and 38 μm, respectively.
Although the grain of the third group samples are refined, the grain size varies, and the uniformity of the grains is 2.079.
Although the grain size is relatively high, it does not affect the uniformity of the grains.
When the magnetic field intensity is constant, the value of the saturation magnetic induction increases with the angle of rotation, and the number for the magnetic domain increases.
The grain was refined, and thus, several grain boundaries exist in the microstructure.

The results show that: Since the beginning of the two-phase region with quenching temperature, the austenite grain size from the initial 4+6 mixed crystal at 740℃, and gradually increased to 10 at 860℃; Austenite grain size and hardenability was directly proportional to the austenite grain size increased from 8μm to 36μm, the biggest change is the hardness 10HRC; Austenite grain size and impact toughness is linear, with the decrease of grain size, the impact energy increases linearly, and the austenite grain size and impact toughness curve fitting.
Effect of austenite grain size on hardenability.
Reduce the grain size, determine the level of hardenability of pearlite and ferrite easier nucleation at grain boundaries, which means increasing the grain size of ferrite and pearlite will generate greater probability [8], resulting in reduced hardenability.
Effect of austenite grain size on the impact toughness.
Grain refinement to improve the toughness of the material as the main reasons: From the perspective of grain boundaries on impact toughness, the grain boundaries are crack propagation resistance, when the grain size becomes smaller, the microstructure of the grain boundary area increases, uniform dislocation density distribution , so that the interface leading edge pileup of dislocations number is reduced, will help slow down the stress concentration, and the impurity concentration of the interface also becomes small, intergranular brittle fracture is also reduced. in addition, crystal high angle grain boundary presence to force the process, the deformation is not uniform, the grain boundary is not easy to produce plastic deformation , resulting in different crystal orientation, but also makes the plastic deformation of the discrepancies.

Normal grain growth is associated with the coarsening of grains with the {0001}< 0211 > orientation.
It is recognized that recrystallised grains do not nucleate as totally new grains.
Grain growth after primary recrystallisation.
Grain growth after primary recrystallisation.
By contrast, the development of the {0001}< 0211 > texture component takes place by a discontinuous recrystallisation process with the migration of high angle boundaries which absorb defects of the deformed matrix and leave behind almost defect-free new crystals. 0 0,02 0,04 0,06 0,08 0,1 20 30 40 50 60 70 Image quality Number fraction (0001)<10-10> (0001)<11-20> 0 0,02 0,04 0,06 0,08 0,1 10 20 30 40 50 60 70 Image quality Number fraction (0001)<10-10> (0001)<11-20> Figure 4.

There is a large number of theoretical and experimental facts proving that the kinetics of recrystallization, deformation, diffusion, grain sliding, phase transformations, etc is determined by grain boundaries.
Clearly, this method can be convenient for description of atomic structure of grain boundaries in a number of special cases of crystallite misorientations and orientations of boundary planes.
The number of chemical bonds of an atom in this case is equal to 7.
It is possible to classify all grain boundaries by the number of restrictions imposed on the fiveparametrical set of orientational parameters.
The average number of bonds per one atom equals to 4 in a bcc structure.

Cold rolling (CR) was conducted on coarse grained (CG) and ultrafine-grained (UFG) coppers, obtained by 1 and 8 passes in the equal channel angel pressing (ECAP), to investigate the effect of grain size on rolling texture.
Moreover the grain size distribution was fairly heterogeneous, with a small number of grains significantly deformed.
As compared, the average grain size of the UFG copper kept the same, although the grain boundaries became more sharply and straight (Fig. 6(b)).
Summary Coarse-grained and ultra-fine grained coppers, produced by 1 and 8 pass ECAP processing, were applied to exclude the influence of the texture before cold rolling and research on the grain size effect on cold rolling texture.
Valiev, Effect of cold rolling on microstructure and mechanical properties of copper subjected to ECAP with various numbers of passes, Mat.

Study of application of time series model in grain yield predition Yueling Zhao1,a, Haiyan Han2, Liying Cao1 , Li MA 1,Guifen Chen1 1Jilin agricultural university, 130118 2Changchun university, 130118 a zyueling@163.com Keywords: grain production, time series ,modeling process, prediction model Abstract: the food forecast is very important for grain production, adjusting the important theoretical basis for grain planting structure, making the food security and agricultural sustainable development strategy.
Introduction The forecast of grain production and adjustment to ensure national food security and grain planting structure has important meaning of strategic adjustment of agricultural industry structure is the objective need of realizing agricultural modernization of food consumption dynamic grasp food consumption trend and direction of change, but the grain sown area and output continued to decline, will pose a potential threat to China's food supply and food security.
Forecasting of grain consumption is the basic theory on the basis of agriculture and grain production structure adjustment, to ensure food security for the nation's future in china.
According to China's grain consumption statistics, time series forecasting models of construction of Jilin province grain, and carries on the forecast to the future trend of per capita food consumption in china.
There are many factors influencing the extrapolation and prediction accuracy, such as consumer preferences, consumer psychology, market grain price and changes.

The corrosion behavior was also affected by the ECAP factors especially the press pass number and the pressing temperature.
The results of potentiodynamic test in Fig. 4, the pitting potential (Epit) increased with increasing the number of ECAP pass times.
Third, the processing route (whether A, BA, BC or C)[12] and the total number of passes imposed on the sample .
For example, in the reference [7] the pitting potential (Epit) increased from about -310mV to +110mV with increasing number of passes.
When pressing the sample in a relative high temperature, it will lead to an increasing annihilation of dislocations within the grains and a consequent decrease in the numbers of dislocations absorbed into the subgrain walls.

This size doesn’t change much with increasing cycles number.
Banded structure became less prominent, and areas of small equiaxed grains became larger with increasing cycles number.
Grain size decreases with increasing cycles number and is about 1 μm after 20 cycles.
MAF cycles number 2 4 6 10 20 Average grain size, [μm] 2.55 2.22 1.51 1.19 1.02 HABs fraction, [%] 26.4 29.1 33.0 34.4 50.0 UTS, [MPa] 405 420 435 440 445 Elongation, [%] 19 20 19 19 19 Microhardness, [HV] 111 107 108 113 115 Strength of oxygen-free copper increases slightly with increase of cycles number.
Ductility showed no dependence on cycles number.