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Development of Micro-alloying Ultra-fine Grain High Strength Steel Produced by EAF-TSCR J.X.
In order to control the number of inclusions in molten steel and form, the processes of deep desulfurization, deep deoxidation and calcium treatment must be carried out subsequently.
Fig.5 The precipitation analysis and EDAX analysis of the sample of finished steel SEM observation was performed on the specimens of finished steel, a large number of round micro-alloy precipitates were found in the specimens with intra-granular dispersion, as shown in Figure 5.
Ultra-fine grains steel the theory and technical progress.
Ultra-fine grain steel and its production technology lecture courses[M].

The number and size of pits still increases and the abrasive grains clearly project from the second to the tenth treatment.
In the case of 21 N, the projecting height of grains increase gradually with increasing the number of treatment till the tenth treatment but the projecting height of some abrasive grains is not enough yet.
In the case of 131 N, the projecting height of grains increase earlier than those at 21 N with an increase of number of treatment and increase approximately up to the maximum height of each grain at the fourth treatment.
Therefore the number of treatment, of which the projecting height of grain becomes steady, is defined as the effective number of treatment.
In the case of 0.0014m/s, the projecting height of grains increase gradually with increasing the number of treatment.

Generalization of Fisher Model for periodically non-uniform Grain Boundary V.L.
Kovalevskaya st., 18. 1) vlgap@mail.ru, 2) valerie_kol@mail.ru Keywords: Fisher's model, non-uniform grain boundary and diffusion regime Abstract: The problem of grain boundary diffusion for a case of boundary grain with periodic heterogeneity diffusion properties is considered.
The dimensionless parameters, forming the system of grain boundary diffusion regimes are determined.
Introduction As a rule, the reactionary interaction in boundaries of grains is accompanied with the change of structure of grain boundary (GB).
(6) The "wave number" is determined by expression: 2 V i bi bi bi D pp k D sDδ =+

The texturing development in these superconductors decreases in an efficient way the number of high-angle grain boundaries, increasing the values of the critical current densities.
The texturing development in these superconductors decreases in an efficient way the number of high-angle grain boundaries, increasing the values of the critical current densities [1-3].
In the study was calculated the grain size distribution.
Table 1: Results of grain size in the samples.
The micrographs show grains in the form of small grains flattened (flake-shaped) plates.

The microstructure of initial CCM alloy contains equiaxed grains with a grain diameter of approximately 50 mm and twins.
The clear grain boundaries of equiaxed grains and twins disappear after HPT processing at a rotation number, N, of 10.
The grain diameter of equiaxied grains is approximately 50 mm.
On the other hand, the clear grain boundaries of equiaxied grains and twins are not observed in the CCM alloy subjected to HPT processing as shown in Fig. 2 (b).
The clear grain boundaries of equiaxied grains and twins, which are observed in initial CCM alloy, disappear after HPT processing. 2.

The value of the varistor voltage depends largely on the number of conducting ZnO grains between the electrodes; this can be set by controlling the thickness of the device or the size of the grains.
Therefore, the break-down voltage of an ideal non-linear grain boundary is at 3V.
Although the voltage drop does not vary for grains of different sizes, the mean grain size and the grain size distribution play a major role in the electrical behavior of a device.
The value of the varistor voltage depends on the number of conducting ZnO grains between the electrodes, and this can be set by controlling the thickness of the device or the size of the grains.
Powder Ł consists of loose, plate-like, dense grains, while powder B is characterized by oval grains with a lower compactness that form small agglomerates that are easy to separate.

This paper presents a mechanism for the formation of grain cutting edges in the micro dressing of coarse-grain polycrystalline cubic boron nitrite (cBN) grinding wheels using a fine-grain diamond dresser.
This paper deals with a mechanism for the formation of grain cutting edges in the micro dressing of coarse-grain polycrystalline cBN grinding wheels using a fine-grain diamond dresser.
As shown in Fig.3, some corase primary cBN crystal grains appear in the flat grain surface of the grinding wheel.
A large number of micro projections exist in the flat surface, as shown in the sectional profiles of the flat planes in Fig.4 and 5.
Figure 6 shows the number of projections that exist in a unit flat surface area, that is, the micro projection density Cm.

It was evidenced that large-sized cluster of grains interfaced by S3n boundaries (S3n CG) emerged in sample B, in which there are moderate preferential grain orientation distribution and {111} grain boundary plane distributions.
The fractions of the different grain boundary types were determined on the basis of the length fraction by dividing the number of pixels of a particular boundary with that of the entire grain boundaries.
Grain boundaries with 1<å<29 were regarded as low-∑ CSLBs or SBs.
The spreading of intensity away from the ideal [111] position is an indication of the relative number of incoherent Σ3 boundaries, as shown in figure 1a-1b.
It is evidenced that in sample A all the grain orientations are random whereas in sample B there is modestly preferred grain orientation of {110}//ND.

1 Abnormal Grain Growth and Texture Development A.D.
Abnormal Grain Growth Theory Upper Limit for Abnormal Growth.
Rollett and Mullins [1] developed a theory for abnormal grain growth as a function of the properties (energy and mobility) of the perimeter of a single abnormal grain embedded in a matrix of grains with uniform boundary properties.
Results Grain Boundary Properties.
Acknowledgments This work was supported primarily by the MRSEC program of the National Science Foundation under Award Number DMR-0079996.

At present work it is based on the Fe-40Ni-Ti alloy to simulate the grain boundary migrated process of HAZ in rapid heating process, observe the action between the boundary and TiN, simulate the grain growth behavior of austenite grains.
The grain size in different heat zone was measured by using the line transect method [5], and the grain number of statistics is at least 300. 18mm 4mm F10mm a b c Fig.1 Thermal simulation test of the sample (a) welding line, (b) HAZ, (c) parent metal Results and Discussions Curve characteristic of rapid heated process The rapid heating up curve at thermal simulation machine was shown in Fig.2.
The grain growth is not obvious at HAZ and parent metal.
If the grain boundary energy anisotropy is significant, in order to reduce the process barrier, the grain boundary curvature changes small during the bypassing process, and if the grain boundary energy basic isotropic, in order to reduce the total area increase, the grain boundary curvature near the precipitates becomes very large.
(2) TiN particles have obvious effect on the grain boundary migration, the grain boundary energy change a little with the grain boundary orientation change.