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In conclude, with the increase of filament number, the uniformity of temperature field improved a lot.
Fig.2 Influence of filament number on the temperature field of the substrate Fig.3 Influence of filament diameter on the temperature field of the substrate The influence of the distance between the hot-filament and the substrate hf on the temperature field of the substrate surface is shown as Fig.4, presumed that the hot-filament Tf＝2400℃, filament number n=12 hot-filament diameter df =0.06cm.
It can be seen from Fig8 that the grains of diamond film were arranged densely; the grain boundary was very clear, and the grain size was uniform.
The grain size at the center of the film was basically same as the grain size at the edge of the film.
(1) The substrate temperature increase along with the increase of filament number, hot-filament diameter, and with the decrease of the distance between the hot-filament and the substrate.

The results indicate that some number of large,coherent precipitates prevents serrated flow by way of trapping vacancies, but small precipitates content do not supress it. 1.
Microstructures of the alloys are identified by the presence of continuous equiaxed grains whose size is about 18-50 mm.
More number of grain boundaries is seen with continuous precipitates in the 16h aged specimens( fig.1d).
A large number of coherent precipitates prevents serrated flow by way of trapping vacancies[9,10].
A number of big, coherent precipitates prevents serrated flow by way of trapping vacancies. 4.

A number of new technologies have been recently reported [3-5], but those new technologies, based on the control of pouring temperature or by the low temperature technique, control the solid morphology.
As the larger stirring power (i.e. 352W), there are a number of the fine grains with globular-like in the microstructure, as shown in Fig.3a.
As the stirring power reduces to 60W, there are a number of the coarse grains with rosette-like and no dendritic-like grains in the microstructure, as shown in Fig.3c.
The broken fragments from primary dendritic crystal grow up the new drifting grains at low temperature to realize drifting grain multiplication and to increase the number of the grains.
The process similar to equiaxed structure in the grains is taken place and the stirring effect makes the grains change into near globular-like [11].

Determination of the parent grain orientation.
When a sufficient number of variants are considered, there is a unique common potential parent orientation which is the searched parent orientation gp [1].
As a result, gp is obtained when the three following conditions are simultaneously met: 1- the variants are inherited from the same parent grain; 2- the number of variants is sufficient; 3- the OR (Δg0) is known.
Insufficient number of variants.
When the number of variants gathered is not sufficient (condition 2), the variants are equally related to several potential parent orientations.

It has to be noted that the average grain size of cube grains (7 µm) is slightly larger than that of noncube grains (6 µm) at the end of recrystallization in the W sample.
In the NW sample, it was found that a small number of cube grains have very large grain sizes at the end of recrystallization, which contribute a lot to the cube recrystallization texture and to the larger average cube size.
These huge cube grains are termed supercube grains [14].
It has been suggested [14] that the growth advantage of cube grains may originate from these supercube grains, while other cube grains grow at a similar rate as noncube grains.
In the W sample, there are a few large cube grains, but their size advantage compared with the noncube grains is not as obvious as the supercube grains in the NW sample.

The proper diamond mixture ratio is the prerequisite factor to Journal Title and Volume Number (to be inserted by the publisher) 155 marvelous property of the blade.
It is shown that for the harder and more wear-resistable granite (such as 657#), the percentages of harder grains and diamond grains with fine mesh number 50/60, 60/70 should be increased for the sake of greater resistance; Otherwise the percentage of 30/40, 40/50 should be increased and the toughness of diamond could decrease a little.
But if the concentration is too high and there are more diamond grains of fine mesh number 60/70, 50/60, the blade will become blunt although wearable, which will affect the cutting efficiency.
The size and shape of grain are different, and protrusion the height of diamond grain varies as well.
If the diamond density equals or exceeds that of No.g.5 and No.g.6, or the number of diamond grains is or goes beyond that of 60/70, saw blade will be blunt, cutting efficiency will be low, and hence the overall benefit reduces.

., with grain-grain interaction.
Residual stresses are created, number of dislocations is strongly increased and grain boundary structure is strongly changed.
The agreement between experimental and theoretical results is strongly improved if one takes into account the second order plastic incompatibility stress caused by grain-grain interactions.
The second order stress varies from grain to grain and it has important influence on the shape of >),(< }hkl{ψφε vs sin2ψ curves.
Let us recall that the stored elastic energy is created a result of grain-grain incompatibilities, i.e., in the regions of grain boundaries.

The average grain size of ferrite shown in Table 1 shows that the average grain size of ferrite decreases as rolling temperature lowered.
The average grain size of ferrite decreases with lowering rolling temperature, while the effect of loop-laying temperature on the grain size can not be easily identified.
Fig.5 shows BN particles on the grain boundary.
Due to the large size of BN particles, they have little influence on the re-crystal grain growth of austenite, the grain refining strengthening and the precipitation strengthening [18].
In addition, pearlite was spheroidized gradually and the number of spheroidized pearlite increased with the reduction of rolling temperature

., As, S, Sb etc. are precipitated on the grain boundary, which cause the noticeable decrease in impact strength.
S.No: Thermal Treatment Cooling Rate (C/min) Biot Number (<0.1) 1.
Annealed 4.6 0.001 The validity of assumption based on Lumped Capacitance computed results can be expressed by Biot Numbers i.e., for a valid assumption the Biot Number should be <0.1.
The as received condition was hot rolled, where equiaxed grains could be seen.
At this point the grain size was reduced to 32 ± 7µm.

The grains of the alloy are refined, round.
A large number of studies have shown that it can narrow solidification temperature range, increase the intensity and plasticity of hot brittle zone, and refine the grains by adding microelements in aluminum-copper alloy [4-7].
Thermal fatigue properties, mechanical behavior of the alloy during solidification and the grain boundary state is closely related to the solidification process of alloy [8-9].
As can be seen from Fig.3, Fig.3 a) shows the microstructure of Al-4.5Cu alloy with no rare earth Ce addition, its grains was coarse, with well-developed dendrite, grain boundaries blurred.
While its dendrite trend has been markedly inhibited when adding some rare earth Ce addition, with a larger number of primary α-Al phase grains, and its grain was small, round, and distributed evenly.