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The peaks at x=0.2 and 0.4 can be found in the standard patterns reported to the ICDD/JCPDS PDF for strontium iron oxide SrFe12O19 (space group P63/mmc (194), file number: PDF#33-1340).
The grains in the doped strontium ferrite film surface are more compactly deposited and smaller than the grains in the undoped one in Fig. 4.
The grains in the middle position of Strontium ferrite film in Fig. 3a are stacked by small grains like balls; the grains in Fig. 3b are stacked by irregular ball grains where there are a number of little grains.
However the grains of undoped strontium ferrite films in Fig. 4 are stacked by grains like peanuts which are about 500nm long and 100nm in diameter direction.
It is possibly because the substitution of cerium or lanthanum could induce the grain size shrinkage and bring more grain interface which changes the surface state and grain surface energy level remarkably.

The experiments were performed with dia-mond wire sawing tools with a length of l = 6 m and a segmentation (number of cutting beads per meter sawing tool) of λ = 40.
This increase in the material removal rate is caused by a higher single grain chip thickness hcu which requires higher process forces in order to ensure the intrusion of the abrasive grain into the work piece material as well as to enable the material separation.
As with that a single diamond grain is subjected to the contact pressure between tool and work piece for a shorter period of time the total intrusion depth for the single grain decreases.
This is due to the significantly increased projected single grain pressure surfaces, stress cross sections and single grain chip thicknesses as well as to increased friction effects.
The reduced number of abrasive grain on the cutting bead surface results in increased projected single grain pressure surfaces, stress cross sections and single grain chip thicknesses.

The initial austenite grain size and hardness were not influenced by ausageing, except for the sample ausaged at 765 oC for 86400 s.
In the heat-treated steel without ausageing (Fig. 3(a)), a small number of spherical and platelet-shaped precipitates were observed within prior austenite grains.
In other words, few precipitates were observed along prior austenite grain boundaries.
The number of precipitates in the steel ausaged at 500 oC was remarkably higher than that in the steel without ausageing, though in the steel ausaged at 765 oC the number was almost the same as that in the steel without ausageing.
Additionally, a drastic change in the number of precipitates was not observed compared with the steels ausaged for 1800 s.

MnO on the steel surface could be in-situ reduced by the bath dissolved Al, the reaction equation is as follows: 3MnO+ 2[Al] → 3[Mn]+Al2O3[15] But if Mn content in the steel is high enough and the formed MnO is in great number, the reduction of MnO will be difficult and cannot be deoxidized completely[13,16].
Two kind of inhibition layer grains were observed in Fig.5(a), some regions are fine, and others are coarse.
The bare substrate provides a clean steel surface for Fe-Al phase nucleation, and the Fe-Al nucleation is in great number, leading to the formation of fine Fe-Al inhibition layer grain.The nodule-like oxide can be thermodynamically reduced by the bath Al, because of a very short galvanizing time of 3s, there was a limit to the size of oxides that could be completely reduced.
Thus the formed Fe-Al grains were scattered and sparse.
In addition, because the amount of nucleation sites was lowered for per unit area, the dissolved Al was sufficient for Fe-Al grains growing into bigger ones[16].

All numbers are in % weight.
The grain growth between CMM and SRM was also studied.
The evolution of austenitic grain size shows a fast growth after some seconds remaining with almost the same size until SRM.
The measured grain size evolution was used to adjust the equation for grain growth to be used in the subsequent predictions of mathematical model [9].
Since some precipitation takes place between CMM and SRM, as shown by TEM investigation (Fig. 2), it is reasonable to suppose that, at least, situation number 2 occurs.

Grain growth occurred after recrystallization in the samples tested at 450°C.
The equivalent stress  and the equivalent strain  were calculated using the relationships: )'n'm3( 3R2 M3    (1) L3 RN2   (2) where R and L are the gauge radius and length, respectively, N is the number of revolutions, M is the torque, m'=( Nlog/Mlog  ) at constant strain, and n'=( Nlog/Mlog  ) at constant strain rate.
Figures 7-8 shows typical examples of the microstructure of the ZEK200 after torsion testing under a strain rate of 0.5 s-1 and quench; at 250°C, the structure is mostly composed by slightly elongated grains, while at 300°C very fine recrystallized grains on several grain boundaries.
At 350°C only a minor fraction of the structure, located in grain boundary regions, underwent recrystallization, while at 400°C, an extremely fine and homogeneous recrystallized structure is obtained, with few elongated grains.
At 450°C the structure underwent complete recrystallization and moderate grain growth.

Figures 3 show a typical grain size distribution as obtained by image analysis.
This observation holds also true for the maximum detected grain size (45 µm original, 95 µm after).
In the case of the rectangular specimens, the maximum grain size increases from 50 µm to 140 µm, despite the fact that the most probable value of the grain size increases only 50 % after heat treating (increasing from 10.15 µm to 15.12 µm).
The dimple size is controlled by the number and distribution of nucleated microvoids.
Ferritic grain size distribution for asreceived tension test specimen.

At present, a number of studies have been carried out to optimize the cube {001} <100> texture in the Cu-Ni alloy substrates obtained by the rolling assisted biaxially textured substrates (RABiTS) process, utilizing heavy rolling and high temperature annealing [1-7].
The cube texture formation during recrystallization were confirmed that the recrystallized cube grains are on average coarser than grains of other orientations, and the cube-oriented grains gain a growth advantage compared to other grains [3, 12].
The majority of grains with non-cube orientations are consumed by cube-oriented grains during grain growth in the strongly textured Cu-45at.
Since further grain growth in the recrystallized microstructure takes place, the frequency of HABs decreases as the growing cube-oriented grains encounter one another, forming new LABs (see Fig. 3).
Recrystallization and grain growth [J].

The results indicate that SiC particles are mainly distributed along grain boundaries, retarding grain growth and conducing to the refinement of the matrix.
Introduction A number of studies have been carried out on particulate-reinforced metal matrix composites.
The α-Mg exhibits fine equiaxed grains with well-defined grain boundaries, as shown in Fig. 2b.
Additionally, some pores are found in grain boundary.
Primary grains are larger relatively with obvious grain boundaries.

Grain size in the different position of SF FGH95 superalloy is very fine and uniform, showing no obvious nonmetallic inclusions and pores.
There are a small number of larger size unconnected-distribution γ′ phase (0.8-1.0 μm) distributed on primitive particle boundary(PPB).
A lot of finer γ′ phase uniformly distributed on grain internal, with size is about 100-400nm.
Cantor, Isothermal grain coarsening of spray formed alloys in the semi-solid state[J].
Journal of Materials Science, 2005, Volume 40, Number 7, 1673-1680 [5] C.S.