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These thermal cyclic conditions are repeated as many times as necessary to produce the required number of parts.
Figure 2 illustrates the stress amplitude versus the number of cycles for different levels of temperatures, for both materials.
The elastic modulus values show a significant and unusual discrepancy, mainly due to a basaltic grain size close to the gauge length.
Strain controlled tests were performed with a larger gauge length (25 mm), in order to reduce grain size effects.
Fig. 8: Evolution of the stress amplitude versus the number of cycles for an applied strain of %4.0± .

The main SPD features are super-large plastic strain and grain refinement of a material under working.
Number of passes was altered from n=15 up to n=30.
The experimental plots for number of passes n=15, 20, 25, 30 are brought together in Fig. 5.
When analyzing Fig. 5, one can see that the increment of microhardness is proportional to number of passes n in the near-contact region.
Vinogradov, Extreme grain refinement by SPD: A wealth of challenging science, Acta Materialia. 61 (2013) 782–817

The in-depth heating permits very rapid processing (cycle times of potentially less than 10 minutes) which is intended to preserve a very fine grain structure in the final product resulting in excellent mechanical properties and the possibility of superplastic forming.
In the past few years the availability of titanium powders, produced by a number of novel processes, have resulted in broad interest in utilizing these lower cost materials for military, industrial, and aerospace applications.
The in-depth heating permits very rapid processing (cycle times of less than 10 minutes) which is intended to preserve a very fine grain structure in the final product resulting into excellent mechanical properties and the possibility of superplastic forming.
That sintering of metals can be done with microwaves became clear in 1988, when Walkiewicz et al [8] determined the heating characteristics of a number of metal powders.
At the very least the rapid cooling preserves a very fine grain structure and results in excellent mechanical properties of the final product.

It was found that the amount of W-rich solid solution in W-10Ti alloy was decreased, because the diffusion of Ti to W was inhibited by a small amount of TiO2 in grain boundaries during the sintering process.
W-Ti thin films with 10wt％-30wt％Ti are most frequently used, in which tungsten serves as the diffusion barrier and titanium prevents grain boundary diffusion [1-4].
Fig.1 (e) and Fig.1 (f) show the magnified micrographs of mixed powders milled for 24h and 36h respectively, it can be founded that these fine particles agglomerate in the form of white flocculent structure, and a large number of fine WO3 particles are stuck on large TiH2 particles.
The diffusion of Ti into W matrix was suppressed due to a small amount of TiO2 in grain boundaries, so the content of Ti in the W-rich solid solution was decreased.

Firstly put all subscriptions under one theme into a matrix (m×n)of 0, 1 with preprocessing, m means the number of subscriptions, n means the total number of predicates.
Firstly all subscriptions under one theme should put into a matrix (m×n)of 0, 1, m means the number of subscriptions, n means the total number of predicates with preprocessing.
The original matching is given event with all subscriptions to compare one by one, when subscriber only coarse-grained event theme, or there are a small number of events content filtering subscriptions, the original matching algorithm can have a smaller space and time complexity.As the density and frequency of TT&C tasks enhance, and the number of message interaction increase,The original matching can not meet the strong real-time requirements.When the number of event and subscription releasing is huge, the message matching strategy is that making full use of the overlaps between different subscriptions, so the repeated partial judgment will only be once.
Program generates events containing 20 properties randomly, and then generates subscriptions containing 5 ~ 10 predicates with the number from 10 to 90.
Firstly all subscriptions under one theme should put into a matrix (m×n)of 0, 1, m means the number of subscriptions, n means the total number of predicates with preprocessing.

The experimental TTT curves determined for a given austenite grain are shifted as a function of the grain size to be simulated through an algorithm where the transformation start time is related to the factor 2N/8, where N is the grain size expressed as ASTM number [1].
It can be effectively used to carry out preliminary sensitivity analyses, including the effect of austenite grain size, in order to select the most promising heat treatment simulations to be performed by the 3D software later.
The minimum soaking time was fixed between 1 to 3 hours in order to austenitize properly the full part, avoiding excessive austenite grain growth and fuel consumption.
Calculated Measured Calculated Measured Solid round 250 - 0.92 209 192-201 9 10-25 300 - 0.70 190 181-192 34 30-40 Hollow round 440 160 1.20 216 206-216 0 < 10 550 180 0.72 195 195-206 28 10-20 Solid round bars with a diameter of 250 mm to 300 mm are critical because it can be difficult to develop adequate microstructures, i.e. with a ferrite percentage less than 30%, at depths > 70 mm, especially when alloying elements of 4130 steel are close to the minimum acceptable values and austenite grain is fine.

Choose the four highest peaks in every XRD pattern and calculate the grain size of TiO2 in the Pd/TiO2 powder by Scherrer formula.
The grain sizes of TiO2 are shown in Table 1.
For the Pd/TiO2 powder calcined at 773 K, the average grain size of TiO2 is 10 nm, which is almost consistent with the result of TEM.
The average grain size of PdO calculated from the crystal face of 101 is 16.3 nm.
Table 1 Grain fineness number of Pd/TiO2 powder CPI (hkl) Size,nm CPI (hkl) Size,nm Anatase TiO2 573K 673K 773K 873K 973K Ruile TiO2 973K 101 7.3 6.4 11.0 16.0 49.3 110 98.7 200 6.8 5.4 10.3 15.0 48.8 101 108.1 105 6.9 9.2 7.0 15.1 40.0 111 162.1 211 6.6 8.1 11.8 14.2 38.1 220 109.3 average 6.9 7.3 10.0 15.1 44.1 average 119.6 CPI:Crystal plane index The crystal lattice constants, axial ratios and cell volumes of TiO2 in the Pd/TiO2 powder were obtained through Rietveld refining of XRD patterns by Topas software.

As one can notice, sample A has 26 wt.% of �-MgH2 with grain size d=9 nm.
In this sample metallic Mg has a grain size of 20 nm.
The milling-induced formation of �-MgH2 has been reported by several authors [2,3,10]; this phase can be considered as a distortion of �-MgH2 since the two hydrides exhibit the same packing type and coordination number.
It is worth noticing that MgO shows halos in the SAD pattern and very broad peaks in the XRD profiles owing to a quite disordered structure, with grain size of 2-3 nm.
For all samples, we have determined a Fe grain size in the 20-30 nm range.

Moreover, in the case of a wheel in which electrically conductive abrasive grains [4] are mixed in, application of the electrical contact sensing with a workpiece will become possible.
The reason why contact sensing could be performed even on the conventional diamond wheel seems to be that the grain size of the diamond abrasives was finer than the roughness value of the wheel matrix.
The size of the diamond abrasive (non conductive) used was SD700 mesh and the concentration was 125 (grain volume percentage: 31%).
The average grain size was 10µm for both types of PCD.
Though details are not shown here on the results of the trueing using a vertical truer, it will be worth describing that the electrically conductive vitrified bonded wheel could be trued with extremely high efficiency requiring far less number of passes for correcting the wheel deviation, namely only one tenth of that required by the metal bonded wheel.

This means that grains in the films are strong oriented in the ‹0002› direction.
The calculated average grain size was 200 nm.
The AFM micrograph for the ZnO film after annealing (Fig. 2b) confirmed an increase of grain size to 400-600 nm.
One can see that the number, form and value of band maxima are differ strongly in high energy range of spectra (Fig. 3,а).
The films had the hexagonal lattice with the strong oriented grains in the ‹0002› direction.