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The starting materials were α-Si3N4 powders with average grain size of approximately 0.5 µm, purity 99.5%, and TiC nanoparticles with average grain size of 140 nm, purity 99.8%.
A minimum number of five specimens was tested for each experimental condition.
The sub grain boundaries formed around the TiC nanoparticles were observed inside the β-Si3N4 grains, which is assumed to cause some grain refinement.
The microstructure of the composite was characterized by fine, elongated β-Si3N4 grains, with larger TiC nanoparticles located at grain boundaries, while the smaller ones trapped inside the β-Si3N4 grains.
The intragranular TiC nanoparticles led to sub grain boundaries and consequently the strengthening by grain refinement.

A number of models for precipitation kinetics have become available in the last years; these have been combined with thermochemical and thermokinetic databases.
Due to the fact that precipitation occurs at the grain boundaries, the growth won't be only volume diffusion controlled.
The parameter λ2 (0.6<λ2<1) reflects the contribution of the grain boundary diffusion of Chromium on the growth kinetics of the Chi precipitates (λ2≈0.6 means only grain boundary diffusion controlled).
There are, however, a number of factors that require further analysis.
Acknowledgements The authors are grateful to the Netherlands Institute for Metals Research (NIMR) for the provision of funding through the programme "Designing ultra high strength corrosion resistance steels for aerospace applications" (project number ) and "Tailoring of processable metastable steels" (project number 02EMM30-3).

Lentil Grain Drying Application.
The values of the parameters hm, kl and kv were obtained by agreement between numerical and experimental data of average moisture content, using the least square error technique, as follows: , (11a-b) where ERMQ is the least square error, is the variance, n is the number of experimental points and is the number of estimated parameters [13].
Figure 2 - Comparison between predicted and experimental [17] mean moisture content of the lentil grain as a function of drying time Figure 3 - Predicted mean temperature of the lentil grain as a function of drying time Fig. 3 illustrates the heating kinetic of lentil grain as a function of the drying time.
Figure 4 - Liquid flux at the surface of lentil grain.
Figure 5 - Vapor flux at the surface of lentil grain.

In absolute numbers this means an increase of only a few percent of the overall composition.
The oscillary frequency was 300...2900 Hz with an overall number of 500,000 strokes.
A larger fraction of grain boundary phase is present, too.
The fraction of grain boundary phase increases, too.
This load had dramatic consequences during one test run with alumina parts where the piston broke before reaching the maximum number of 500,000 strokes.

Until recently, the severe plastic deformation (SPD) just above Ar3, which enables the strain induced dynamic transformation (SIDT) of the unrecrystallized austenite into ultrafine grained ferrite, followed by the accelerated cooling preventing the grain growth, has been considered [1-5].
Ultrafine ferrite grains are shown in Fig. 5(a) and (b).
It becomes severer with increasing number of pass and cooling rate, and decreasing rolling temperature and test temperature [5,6].
SIDT ultrafine ferrite grains, and second phases aligned along the rolling direction on rolling plane, were observed.
[4] "Development of High Strength Structural Steel with Fine Grain (III) ", POSCO Report, 2001

Thus, meta-models which are extracted from the results of a limited number of FE simulation studies are more and more used to find the optimal process design parameters.
The accuracy of an RSM is highly dependent on the number of input data points.
The austenitic grain size was determined using the linear intercept method.
DRX kinetics (1) Peak strain (2) Critical strain (3) Steady-state strain (4) Dyn. recr. grain size (5) Grain growth (6) Design of experiments (DOE).
To predict GG the annealed specimens were analyzed in terms of grain sizes.

However, a number of Mg12Zn(Y,Gd) phases and Mg(Gd,Y)Zn phases retains after heat-treatment result that the increase of concentration in the grains is not significant, and so the solution strengthening effect on the YS is not also obvious.
The dislocations are gathered at the grain boundaries finally, and thus it is particularly important to prevent the dislocation movement with the secondary phase at grain boundary.
Nevertheless, with the heat-treatment process, the reduction of the number of LPSO phases and effect of dissevering on the LPSO phase by Mg(Gd,Y)Zn phase result the decrease of UTS and elongation.
These phases are network distributing along the grain boundaries discontinuously
However, the reduction of the number of LPSO phases and effect of dissevering on the LPSO phase by Mg(Gd,Y)Zn phase result the decrease of UTS and elongation with the heat-treatment time prolonged.

The present authors expect that ECAP would be effective in matrix grain refinements as well as enhancing matrix-particle bonding with an aid of shear stress which breaks surface oxides.
In particular, the effect of the number of ECAP passes was discussed. 2.
The grain size of the Cu matrix decreases mainly during the first two ECAP passes and is almost steady during further processes, similar to the saturating strain-hardening behavior with the number of passes in general ECAP data, although not shown here.
The decreases in matrix grain size and inter-particle spacing due to particle redistributions increase strength and strain hardening of the composite by decreasing dislocation mean free paths.
Hence, ECAP has one more viable industrial application; homogenization of microstructures of bulk composite parts in addition to grain refinement.

Austenitic grain pattern is observed with Olympus GX71 optical microscope.
Figure 5 shows that the original grain in the deformed structure is obviously stretched at the strain rate of 10s-1, grain boundary suffers serious fragmentation, and a small amount of dynamic recrystallization grains appear near the triple junction and grain boundary, the grain size being smaller, and the amount of cores decreasing.
Compared with the deformed structures at strain rate of 10s-1 as shown in Figure 5, the dynamic recrystallization area of the deformed structures at strain rate of 1s-1 expands, and the original grain is gradually replaced by dynamic recrystallization grain with the size of newly generated grain enlarging and the number of cores decreasing.
The dynamic recrystallization behavior occurs more fully in the deformation organization, and the grain boundaries of the stretched original grains become basically obscure, larger grains of dynamic recrystallization being formed in the boundary zone, and being distributed in a homogeneous manner as shown in Figure 6.
Meanwhile the dynamic recrystallization is not complete under higher strain rate with newly generated grains mainly concentrated in the area close to the grain boundary of the stretched original grains, the proportion of which being low and the distribution of which being uneven.

The results show that the addition of B makes part of Zr become precipitation present in grains and grain boundaries as the small plate sheet of second phase from solution.
With the B sample test results of the XRD When we made the energy spectrum analysis using Inca Energy EDS, there ware no B elements in the spectrum, because the atomic number of B is small.
The analysis of the energy spectrum shows that there are fine precipitates no matter on grain boundary or inside of the grain.
According to the analysis of the energy spectrum, the second phase particles of Zr containing are appeared both on grain boundary and in inside of grain.
And making parts of Zr precipitated in inside of the grain and on the grain boundary as the form of flaky second phase particles from solution.