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N= turn number.
N= turn number.
N= turn number.
N= turn number.
N= turn number.

Within the reduction of 60% the hardness number reached out to 299.2 BHN, most harder than other sample.
Relevance of Hardness Number and Variety of Reduction Chart Tensile Test Result.
Degradation at 60% of reduction caused by high hardness number which makes brittle on the material.
Fine grain size indicates the material becomes more brittle as compared with the A0 sample.[8] Fig. 6.
Fine grain size indicates the material becomes more brittle as compared with the A0 sample.

The second phase particles that precipitatesin the steel has a pinning effect on the grain boundary, thushinder the grain boundary migration and suppress the grain growth, for which, on purpose of grain refinement and improving material properties, the particles of the second phase are introduced into as an effective control method[5-8].
As can be seen from the picture, some strips wereon the internal grain boundary of theexperimental steelmicrostructure, which analyzedby EDS was main component of component C, Fe, Cr, while the matrix was also C, Fe, Cr, but the C, Cr peak is significantly higher of grain boundariesthan that of the substrate.
Grain boundary strip Matrix Fig. 4.
(2) Under the experimental conditions, the experimental steel also precipitated a rectangular second phase particles of (NbTi) CN phase and TiC, which were sparsely distributed with the size of 100 ~ 300nm and below 30nm, while some phases were distributed as a number of strips in the grain boundary which mainly are C, Fe, Cr.
New Ultra-fine Grained Weathering Steel in Grade of 450 MPa, J.

At 150oC, the crack mainly progresses at grain boundaries of recrystallized grains.
The fatigue life was defined as the number of cycles in which the maximum load was reduced by 20%.
This means that fracture occurs in grains and grain boundaries so that the fracture mode is the mixed mode of transgranular and grain boundary fracture.
Since the number of the origin of the crack is relatively large, fatigue lives degrade at 150oC in the Sn-3.5Ag-0.5Cu-0.07Ni-0.01Ge alloy in which fracture mainly occurs in the grain boundary.
Although most of recrystallized grains formed at 150oC has misorientation of 5-15o, several recrystallized grains have high angle grain boundaries which misorientaion are over 15o.

According to EN ISO 643 was rated by number G = 7 / 8.
Ferritic grain size was G = 7.5 to 8.
Ferritic grain size was G = 9.5.
Ferrite grain size is quite similar in observed regions and according to EN ISO 643 was rated by number G = 9.
Ferritic grain size varied between number G = 7.5 and G = 9.

Note the sharp transition between the equiaxed grains from the top of one layer and the dendtritic grain growth that initiates at the bottom of the molten pool.
Instead, the grains grow continuously through the deposit layer boundaries in the intermediate region, with finer equiaxed grains in the final (top) layer.
Note that the depth of the molten pool during the preheat pass is the maximum depth that occurs, regardless of the number of subsequent layers deposited.
The width of deposit increases with increasing number of layers due to spreading of molten pool from build up of heat in deposit. 4.
After two layers, banding is clearly evident where the microstructure segregates with distinct regions of dendrites, columnar grains, and equiaxed grains.

SiC crystalline grain is round grain shape or ellipse shape, crystalline grain size is about 50nm and well-distributed on Si3N4 crystal boundary, small number of SiC crystalline grain exist in Si3N4 crystalline grain.
We find that SiC crystalline grain in Si3N4 crystalline grain is smaller than the grains on crystal boundary, most of them is under 20nm.
In Si3N4 single materials Si3N4 crystalline grain grow soundly, most of crystalline grain is long column shape, the ratio of diameter is 5-6, and there are unusual big crystalline grains.
This shows nanometer SiC crystalline gain can restrain the growth of Si3N4 crystalline grain effectively, especially SiC crystalline grain on Si3N4 crystal boundary which nail-picked on Si3N4 crystalline grain.
Fig.3 shows SiC crystalline grain nail-picked on Si3N4 crystalline grain.

No carbides inside the grains were observed by SEM.
The peak positions of a Fe-Cr, M6C (Fe3W3C) carbides and Fe-C agreed well, respectively with the ICDD card numbers 34-396, 41-1351 and 52-512.
Referring to Fig. 4, brief descriptions of each stage (indicated by number in the Fig.4) are given below: 1.
The primary d ferrite grains nucleated and grew 2.
The difference in nano hardness value of ferrite is due to the intrinsic difference of each grains, dislocation density, work hardened grains in the near surface region and the presence of dispersed fine carbides around the grain boundaries [15].

The fine grain is good for performance.
Fig.1 Schematics of suction casting and blade casting Result and discussion The Ti-47Al-5Nb-0.5Si alloy structure can be seen from the figure 2, and Ti-47Al-5Nb-0.5Si alloy structure has small grain size, with an average grain size of 20um or less, and some grains even smaller than 10um.
According Ti5Si3 phase distribution, it can be seen, the Ti5Si3 phase mainly in the grains, and there are a small number of Ti5Si3, which proved, formed during the solidification phase Ti5Si3 in addition to providing nucleation particles, but also hinder the grain growth during solidification, thereby grain refinement.
If more than B2 phase, the α grains are more susceptible to obstruction of the B2 phase on growing, while the β-phase stabilizing elements Nb, Nb elements are added, is conducive to the formation of the B2 phase, so that the grain size becomes thin.
Long term creep of TiAl + W + Si with polycrystalline and columnar grain structures [J].

Both the grain and grain boundary conductivities have been determined as a function of temperature in the range of 773-973 K.
The ohmic resistance value has been considered as a complex number which contains series of various electrical elements.
The grain and grain boundary separation can be slightly identified at lower temperature (673-773 K).
Influence of Grain and Grain Boundary on Electrical conductivity Though the sample has a larger grain size (~1-2µm), the ionic diffusion through grain boundaries (GDC-GDC and Ni-GDC, NiO-NiO) is more sluggish than grain interior.
Therefore NiO-GDC grain contacts are to be expected in Ni (50:50) composition at lower temperature (673-873K) whereas number of homo contacts can be higher than hetero contacts at higher temperature (823-973K) range in which grain resistance (RGi) may be predominant over boundary resistance (Fig. 9).