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A mixed grain ferrite was obtained when deformed at this temperature.
The tiny bainite lath depends on the grain size of prior austenite.
The austenite is refined through accumulated deformation, so the total grain boundary area is increased.
The laths formed around austenite grain restrain the laths from traversing through the austenite grains, therefore thin and relatively short intersecting structures of bainite laths were formed.
Because of coarse and sparse distribution, this TiN cannot prevent grain growth validity.

Grain controlled material was mainly made by the 3 steps of pouring, cooling and heat adjustment.
But, in the No. 4, the primary α phase was partially rosette type and more globular grains were observed.
Compared to the microstructures of Fig. 3, more globular grains were formed.
When the stirring time increased from 120 sec to 300 sec, the morphologies of the grains was finer and more globular.
But, when the stirring time was 600 sec, as shown in Fig. 4 (f), solid grains coalesced and the number of the globules was fewer than in case of the 300 sec stirring time, as shown in Fig. 4 (e).

Hennings et al. reported that the Nb/Co ratio had great influence on the grain growth and dielectric properties in the system BaTiO3–Nb2O5–Co3O4[1].
In this work, the fine grained BaTiO3-based ceramics with different milling time and sintering temperature were prepared.
The shell was consist of a series of different phases with various concentrations of dissolved additives in BT grain boundaries.
Fig.6(d) shown that there were some secondary-phase in the grains.
Moreover, the grains grew by rising the sintering temperature.

Moreover, it can result in an increase in the number of grains participating in cutting within a unit time and a reduction in the critical back engangement for single grain.
Beginning with an analysis on the relation between the dynamic or static parameters of wheel topography and the grinding process, the space between dynamic effective grains p, grinding wheel speed vs, workpiece feed speed vw and back engagement ap are determined as design variables.
Taking the minimum specific grinding energy as optimization object, workpiece surface roughness, chip space and the average heat flux in the grinding zone as restriction conditions, an optimization design model can be built up as follows [2]: ( )                    > > > <       ≥      − − ≤            = − − − − − − 0 0 0 2 4 32 1 1 34.0 min lim 8 3 8 3 4 1 4 3 4 1 0 2 1 2 32 2 2 0 5 2 5 2 5 6 8 1 8 14 1 4 1 0 p w s spsw w sp s w ig i a ss w sp s w s a V V qdaVVP J KR da V V Ptg hd h VV R dV V ctgW da V V PKe θ π θ (1) where es is the specific grinding energy, K0 is a coefficient related to material, W is the mean space between grains, θis the half conical angle of a grain, ds is the wheel diameter, Ra0 is the required surface roughness, V is the grain volume in unit volume wheel, dg is
the diameter of the conical grain, Materials Science Forum Vols. *** 407 hi is the protruding height of grain, J is mechanical equivalent of heat, Rw is the ratio of the grinding heat flowing into workpiece, qlim is the critical heat flux.
Table 1 The parameters of the grinding wheel topography matching with different grinding processes Grinding parameters Optimazation parameters of the grinding wheel topography Grinding process Back engagement ap (mm) Feed speed vw (m/min) Wheel speed vs (m/s) Gerain size (mesh) Protrusion (%) Space between effective grains P (mm) Common grinding 0.001~0.05 1~30 20~60 120/150 20 2~5 High speed grinding 0.003~0.05 1~10 80~200 120/150 20 2~5 Creep feed deep grinding 0.1~30 0.05~0.5 20~60 80/100 30 6~15 High efficiency deep grinding 0.1~30 0.5~10 80~200 80/100 50 6~15 Enhance Heat Transfer in the Grinding Zone to Effectively Control the Workpiece Surface Temperature at the Lowest Level Even in the Case of a Heat Flux much Higher than the Critical Value.

Numerical studies choose same conditions as that of experiments; i.e. an averaged Mach number of 0.3 at the 5th row throat section while Reynolds number varying between 9000 and 36000.
The wall surface roughness is set at hydraulically smooth regime with 1.5-5.0 microns of sand grain roughness, referring to material of cooling blade specimen.
The influences of surface roughness are clearly seen with wall sand-grain roughness varying from ‘smooth’ condition up to 100 microns.
Figure 3b presents CFD predicted Nusselt number at four different Reynolds numbers Red5=9000; 18000; 27000 and 36000.
Influence of surface roughness and Reynolds number on pin-fin HTC End-wall HTC predictions.

Single crystalline coatings should further improve oxidation resistance because high diffusivity paths along grain boundaries would be eliminated.
Optical micrograph of the longitudinal cross-section: heterogeneous nucleation at the surface leading to spurious grains at the top of the coating.
Shank, Development of Columnar Grain and Single Crystal High Temperature Materials through Directional Solidification.
The role of curved isotherms on grain selection.
Journal of Laser Applications, 1999. 11(Special number: Laser Applications Around the World, Invited Reviews from Amongst The World’s Leaders, Part 2): p. 64-79

It was confirmed that small additions of Co-doping promotes densification, grain growth and ionic conductivity compared to pure 8YSZ.
As Huang and Lee noted, decrease in densification can be attributed to the increase in cobalt oxide concentration in the sample, which cause an increase in number of generated oxygen vacancies because of the different states of Co2+ , Co3+ and Zr4+ [6].
The left semicircles results from the grain resistance, while the right one is due to grain boundary resistance.
It was confirmed that small additions of 3 mol % of YSZCo promotes densification and grain growth for the pure 8YSZ.
In addition, 3 mol% of YSZCo showed low in grain resistance and raise in ionic conductivity with a value of 1.36 x 105Ω− 1 cm− 1.

The different parameters such as lapping time, load, slurry flow, slurry concentration, abrasive grain sizes, rotating speed effect on surface roughness and material removal volume are studied.
Table 1 Material properties Material name Material properties BK7 optical glass mohs hardness: 6.5;density:2.5-3mg/mm3; thick: 2mm white corundum abrasive mohs hardness: 9;grain size:#180,#280,#320,#500,#600,#800,#1200,#2000 Polyurethane polishing pad shore Hardness:55-95; Type Model:IC1000 2.5-3mg/mm3 Polish a piece of BK7 optical glass each time in accordance with the processing parameters the experimental design.
Fig.3 shows that with the smaller size of the grain, surface roughness, material removal become smaller and smaller.
Fig.3 Grain sizes vs. surface roughness Fig.4 Concentration vs. surface roughness and material removal and material removal Slurry Concentration.
When slurry flow rate is smaller, there is not enough slurry flow into the place that between the workpiece and platen, the number of grits participated in cutting is smaller, so the surface roughness is relatively large in the small slurry flow rate.

Number of Experiments Parameter Rotational Speed (RPM) Burn of Length (mm) Weld Time (second) 1 1360 1.8 30 2 1360 3.2 3 1540 1.8 4 1540 3.2 5 1750 1.8 6 1750 3.2 All the experiments were variable rotation speed three level and two burn of length level of the process and the weld time was kept constant.
(a) TMAZ, Left Part (b) Weld Zone (c) TMAZ, Right Part (d) Base Metal Figure.3 Interface of specimen welded at 1360 RPM Weld Zone (WZ) is a more refine grain structures lead to fine grain.
The effects of rotation speed, as the grains are compress in the direction of rotation.
Likewise, weld zone has fine grain and eutectic phase (Mg2Si) were mixture with aluminium phase (α) by eutectic phase dispersed throughout the weld zone as shown in Fig. 3 (b) because the rotation speed of the two-phase mixture together and Fig. 4 (d) obtained reveals aluminums matrix phase (α-Al), the microstructures shows that grain globular structure shape.
There is also a region of very fine grains in weld zone (Fig. 5 b) the high rotation speeds lead to high thermal during friction welding.

In addition, a large number of carbides were precipitated at grain boundaries during lower temperature intervals (from 700 to 800°C).
When the temperature reached above 1000°C, the precipitation of carbides at grain boundaries became more apparent as temperature increased, displaying comparatively high intergranular corrosion sensitivity.
In other temperature intervals in heat treatment, however, less precipitation of carbides in grain boundaries was observed.
Moreover, as shown in the figure, even if there were grains completely encircled by carbides, their grooves corroded at grain boundaries were still very narrow, a proof of their low intergranular corrosion sensitivity.
Prediction of Grain Growth Behavior in HAZ During Gas Tungsten Arc Welding of 304 Stainless Steel[J].