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However there has been no standardized test available to assess and compare material, and researchers and companies in the field have devised a number of different methods to show superplastic properties.
Some data is presented showing how the properties of fine grain Ti-6Al-4V titanium alloy are derived and presented using the standard.
It has been found that the amount of time needed to fully stabilize the temperature can be quite long, and there is a danger of grain growth, oxidation or other detrimental change in some materials that affects its superplastic properties.
A number of tests at different strain rates, temperatures etc. can be presented on the Same graph.
The default temperature and strain rate is that for maximum 'm', and the default strain is 0.693 (100%). 0 5 10 15 20 25 30 35 40 45 50 0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 2 True strain True stress MPa 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 1.1 1.2 1.3m value Figure 5 SPF Properties of Fine Grain Ti-6Al-4V alloy at 775C, transverse direction.

SEM images show granule morphology which yield smaller grain size with increasing of RF power.
The G peak position shift to higher wave number and the ratio of the peak intensity ID/IG increases with increasing RF power.
In our experiments, 2x2 cm2 aluminum (Al) substrates were pre-treated by scratching with diamond powder of grain size ≤ 0.1 µm.
Samples in Fig. 4(a), 4(b) and 4(c) exhibit cauliflower-like granule morphology with approximately 1 µm in diameter, while sample in 4(d) shows finer grain structure.
This shift in G peak position to the higher wave number corresponds to more disorder in the structure and hence more sp2 fraction in the DLC films [10].

As shown in Fig.3(a),(b) and (d), with aging temperature increasing, the β-phase continuously precipitates along the grain boundaries.
It shows that grain size is more uniform with time increases.
It shows that the grain size gradually reduces with cryogenic time increasing, and there is more subboundary partially, resulting in grain refinement in local.
The interaction between sub grains and dislocations enhances the structural stability and improves mechanical properties of alloy[5].Therefore, cryogenic treatment refines grain and improves mechanical properties, the comprehensive mechanical properties is best by direct cryogenic treatment for 72h.
When aged at 175℃ for 15h, elongation reached 18.3%. 3) The effect of direct cryogenic treatment was better than solution and then cryogenic treatment, and grains are tiny.

In the simulation of the microstructure the assumption is taken that the workpiece before the deformation has a uniform structure with the same grain size at any point.
Fig. 5 - Change of grain size during multipass deformation In the first pass after the helical rolling the difference in average grain diameter between central and surface area was 8 μm; after pressing in the matrix this difference reached 7 μm.During the second pass the grinding of grain during helical rolling is not as intense as in the first pass.
Here, the average grain size in the surface area was 8 μm, in the central zone was 13 μm, i.e. the difference was 5 μm.
During subsequent pressing in the matrix, the average diameter of the grain was reduced to 6 microns in surface area and 10 μm in the central zone.
When pressing in the matrix average grain size decreased to 3 μm in the surface area and 6 μm in the central zone, i.e. the difference of the values was only 3 μm.Thus, after study of multi-pass deformation model it was found that with increase in the number of passes there is not only a general decrease of average graindiameter, but also the gradual equalization of this parameter between the central and surface area.

Fig.5 indicates that the matrix grain of AAS grows well with a good interfacial bonding pattern, many nano-scale particles (SiC or Al2O3) are well dispersed in the alumina matrix, most of them are located within the matrix, and the others are located on the grain boundaries, which forms the the inter/intragranular structure.
However ,the fine SiC particles play an important role in lowering the boundary mobility of alumina matrix and inhibits the grain growth[6], therefore Materials Science Forum Vols. *** 245 the homogeneous and densified body should be fabricated at 1700℃.
The thermal expansion mismatch between SiC and Al2O3 will cause the tensile stress around nano-scale SiC located in the matrix, which may be transmitted to the grain boundary via alumina matrix and become a compressive stress that is benefit for strengthening the grain boundary and can compel the crack propagation into the matrix not extending along the grain boundary.
Otherwise, there are more dispersed particles in AAS than that in AS, perhaps there be a large number of nano-scale Al2O3 included into Materials Science Forum Vols. *** 247 the large micro-scale Al2O3 grain.
It was reported that the thermal expansion coefficient of nano-scale Al2O3 is higher than that of the larger micro-scale Al2O3 grain [9], so that the compressive stress field will be occurred.

During the above deformation, grain boundary can be seen clearly.
With the increase of cold rolling deformation, grains along the rolling direction were elongated, manifested by polygon grains gradually become elongated, flattened shape (Figure 6).
That may be the main cause of grain boundary exists between quantitative carbide.
In the course of cold working, carbide grain and grain boundary may be resistant to the deformation of slide, led to block up grain matrix deformation [9-12].
Because GH536 alloying degree is high, the stacking fault energy is low, cold deformation produce a number of slip, primary stability in brass type texture ({110}<12>), which is due to the 45 degrees of shear band deformation, C and B stable orientation, with the form of variable increases ceaselessly, grain turning to the two orientation.

Grinding characteristics of ceramic corundum is carried on, study show that the size of ceramic alumina grits range from 0.067 to 0.005 μm, The grinding passivated tiny grains of ceramic corundum oil-stone broken and fall off timely, which is beneficial to oil-stones, self-sharpness.
The superalloys contain a large number of carbides, nitrides, oxides, and metal intermetallic compounds, these carbides are all cubic lattice, such as TiC, NbC, VC, Cr23C6, Cr21(Mo,W)2C6, Cr7C3 etc.
Table1 Deep-hole test results of oilstones Number temperature [℃] Internal external wear loss of workpiece [mm3] wear loss of oilstone [mm3] Oilstone hardness 1# 2# 3# 4# 5# 6# 7# 8# 75 55 58 58 56 65 67 69 57 43 51 51 47 53 58 61 3897.18 6130.58 5580.58 8403.75 5035.23 6145.6 4450.02 3890.36 2448.60 3936.27 3024.44 4848.21 3936.33 4032.36 2496.43 2256.19 K M L N M K M K Analysis of test results Analyze from overall points of view, the efficiency of ceramic corundum is much higher than others honing superalloy inconel 718 with high grinding ratio, as well as the processing efficiency of single crystal alumina is higher than white corundum(Fig.3，Fig.4).
Ceramic alumina abrasive was produced by Sol-Gel process and sintering[5], a large number of crystals of sub-microcrystalline was formed (dimensions between 0.067 ~ 0.005μm)in the molding process, the size of micro crystal structure is about ordinary corundum abrasive crystals 1/50 ~ 1/100, or even small, and tough.
Under the action of the grinding force blunt tiny grains of ceramic corundum fall off from abrasive gradually, new micro-cutting edge exposed constantly, which is self-sharpening of the abrasive(Fig.5).

A generalized and simplified model highlighting abrasive grain motions for lapping process has been proposed [3, 4].
Some small abrasive grains are driven into the work-piece by the relatively large grains.
The surface irregularities of the lapped work-piece depend upon a number of factors such as machining variables employed during the machining process.
The outliers versus number of runs in Figure 3(a) shows design variables randomly scattered and there are no outliers.
Domfeld: An investigation of materials removal mechanism with grain size transition, J.

From the figure, it can be observed that the as-evaporated Al thin film is crystalline in nature with (111)-oriented grains at 38.4o.
This could be due to a more significant grain growth within the Al thin films as the annealing temperature increases.
The significant grain growth increases the average Al grain size which then leads to reduced density of grain boundaries within the film.
As a result, number of electron scattering with the grain boundaries reduces and leads to reduced sheet resistance of the film [14].
This could be due to reduced number of electron scattering with the grain boundaries at high temperatures.

Introduction ECAP (Equal Channel Angular Pressing) is a very interesting method for modifying microstructure and producing UFG (Ultra Fine Grained) materials.
The Sc and Zr additions provide particles that impede grain growth at elevated temperatures to enhance superplasticity [13,14,15].
The grains are reduced in the 1-pass 6082 processed sample (Fig.3a), and different crystallographic orientations appear in the deformed grains.
Fig.8 shows the equivalent strain of 6082Zr and 6082Sc as a function of number of ECAP passes for the outer, the inner and the center mesh elements at the starting process orientation.
Fig.8: Equivalent plastic strain of 6082Zr and 6082Sc as function of number of ECAP passes Fig.9: Microhardness map of 6082Zr alloy (a) and 6082sc alloy (b). 0246810 0 1 2 3 4 5 4th pass 3rd pass 2nd pass Plastic Equivalent Strain (PEEQ) Time [s] inner center outer Al6082Zr 1st pass 0 2 46810 0 1 2 3 4 5 4th pass 3rd pass 2nd pass Plastic Equivalent Strain (PEEQ) Time [s] inner center outer Al6082Sc 1st pass b Outer Side a Outer Side Conclusion The meaningful conclusions of this study can be summarized as follow: After one ECAP pass the grains of 6082 alloy are thinned and show different crystallographic orientations while after 4-pass via route Bc both 6082Sc and 6082Zr show ultra fine crystallites having very similar size in spite of the different starting grains size of the two alloys.