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The early provision of natural power to replace or augment human and animal muscle power came from the widespread use of sail wind mills and water wheels of various designs used for grinding grain and for pumping irrigation water.
Wind power is still used for pumping water, irrigating the farm lands and grinding the food grains in addition to generation of electricity.
Table 1 shows number and capacity of turbine in different sites of this region.
Table 2 shows number and capacity of installed turbines in this region also figure 5 shows plan of site and turbines in this region.
Table 2 Number and capacity of installed turbines in Binalood region Row Site Total capacity Number of turbines 1 Binalood 13200 20 Fig. 5 Plan of site and installed turbines in Binalood region (Red point are place of turbines) Investigating projects Some of important investigating projects are as follow: Sahand wind turbine project.

Therefore, when the alloy undertakes deform, the movement of one crystal grain was constrained by the neighboring grains, then the stress concentration occurred at the grain boundaries, even the intercrystalline crack happened.
The other reason was the grain size of polycrystalline Cu-base SMA materials was bigger than TiNi alloy very much.
Now the researches on Cu-base SMA were focus on grain refinement and texture reinforcement.
Recoverable strain and number of cold-heating circulation until fracture was common performance index to SMA.
Tab3 the number of cold –heating circulation of different alloys samples Alloy CuAlNiBe CuAlNi CuAlBe Number About 750 465 550 The data in table 3 showed that fatigue life cycle of CuAlBe single crystal was about 90 cycles more than CuAlNi.

Due to an increasing number of functions, these valves show an increasing number of cross holes.
The grinding stone is made of aluminum fibers and is available with different grain sizes (see Fig. 3).
The selection of the grain size mainly depends on the workpiece material.
Grain size 400 (A) and grain size 220 (B) Further possible tools to deburr cross holes are springy tools.
But the processing time increases since a higher number of circulations is needed to process the complete intersection.

In both IC and SIC initiation mechanisms, the crack nucleation is induced by inclusions and the final fracture is controlled by propagation of a ferrite grain-sized crack into matrix grain.
The metallographic specimen sectional photos of double-notched specimens at -130 °C showed that significant deformation occurred at the notch root, and the polygonal ferrite grains were elongated to fibers along the tangential direction of the notch significantly, indicating that larger plastic deformations had been produced at the notch root before fracture, which was consistent with that a large number of strip cracks or ductile tearings were observed in the fracture morphology, shown in Fig.4(b).
Moreover, the residual micro-cracks of ferrite grain size existed at the front of notch root,.
If the micro-crack has enough size, it will produce enough stress concentration at the adjacent matrix grain boundary, and may expand to adjacent ferrite grains with the effect of applied normal stress and the normal stress produced by dislocation pileup, then to form the micro-crack of ferrite grain size.
If the maximum normal stress syy is less or the micro-crack of ferrite grain size is too small or the direction goes against the expansion, the residue crack of ferrite grain size will remain in the specimen (Fig. 4 and Fig. 5).

For both orientations simulations were started with equal number of dislocation loops for each active system, distributed randomly on their slip planes.
Simulations with similar boundary and initial conditions were carried out in (111) oriented grains.
However, the rate of increase in stress for comparable increase in plastic strain (rate of strain hardening) was found to be significantly higher in (111) grains than in (001) grains as shown in Fig. 5(a).
For a dislocation with Burgers vector b in an FCC crystal, beffective = bsin60cosq (3) where q is the angle between slip plane and the plane of film. cosq is 1/√3 for (001) grains and 1/3 for (111) grains.
So a higher density of dislocations is needed in (111) grains to get similar plastic strain as (001) grains, as has been reported experimentally in Ref [13].

Cracks stop in front of barrier grains with unfavorable orientations and crack tips blunt.
At the same time, a microcrack was also appeared in grains in the other side (see fig 4d, arrow).
Then the applied load increased to 440.9MPa (see fig 4e), cracks acrossed the whole grain and deflected along the layer direction of the next grain in which large amount of microcracks initiated (fig 4f, encircled by the black curve) on the grain boundary.
Also, another microcrack initiated in another grain.
(2) The ductility of the alloy at 400℃ was superior to that of room temperature because of large number of microcracks produced at 400℃

The number of pulses above a given potential threshold (COUNTS) is related to the Barkhausen jumps in the area of the measurement.
The results showed that the proeutictoid ferrite was the dominant phase with the ferrite grains had polygonal, equiaxed morphology, while the pearlite grains characterized with lamellar morphology.
Finally, the FZ (Fig. 2(c)) was characterized by non-equiaxed ferrite grains, due to the presence of featherlike bainite grains (upper bainite).
The HAZ was consisted of coarser grains, which leaded to lower MBN values.
The ferrite grains were noted with F, while the perlite grains were noted with P Microhardness.

The size of grain is small.
The alloy Co element prevents the grain growing up effectively.
The grains have grown up, and the distribution grain size is uneven.
The characteristic feature of the edge fracture morphology is the oval dimples; micro fractograph on morphology is mainly made of a large number of small dimplesand a few large dimples.
Because of the dissolved second phase are multitudinous, it makes tthe number of dimples significantly increase, then show good plasticity and toughness.

This leads in many cases to an increasing number of defects occurring especially in welded joints.
EPRI defines a high-temperature creep in the range 480 - 510 ºC for grade 91 steel and divides it into 5 classes: Class 1 = no damage, no cavities are present in the material Class 2 = isolated creep cavities located randomly at grain boundaries that can only be detected metallographically Class 3 = oriented cavities with numerous occurrences at grain boundaries, oriented in the direction of the main stress in the material Class 4 = microcracks formed at grain boundaries, where cavities coalesce leading to the formation of a separate microcracks Class 5 = macrocracks, formed by joining microcracks with other cavities on multiple grains of the structure The EPRI findings result in the detectability of creep damage in class 4 and 5 creep, exceptionally in class 3.
This is the so-called failure of the fourth type caused by a significant accumulation of plastic deformation, nucleation, growth, and interconnection of cavities at the grain boundaries and in the final phase by the propagation of the main crack, see Fig. 4, while the fracture state is characterized by a relatively high concentration of cavities even in the localities of the intercritical zone, remote from the formed main crack [2].
The cuts are made by the metallographic cutting saw Discotom 10 approx. 5 mm in front of the line indicating the largest number of indications in the given place.
For such test specimens, however, it is important to find out the most accurate information about these defects, using metallographic analysis as the best option, which will give us comprehensive information about the test area (shape of the weld, HAZ size; number, position, type and dimensions of defects, etc.).

For the laminated composite of TiB2-based ceramic and 1Cr18Ni9Ti stainless steel, high- magnification FESEM images of the intermediate nearby ceramic matrix and the intermediate of 0.5 mm away from the ceramic matrix showed that TiB2 phases developed in the form of the platelets, surrounded by the irregular TiC grains, whereas Fe-Cr-Ni metallic phases were distributed at the boundaries of TiB2 and TiC phases, as shown in Fig. 6.
Meanwhile, comparing to ones at the inter- mediate nearby the ceramic matrix, in the intermediate of 0.5 mm away from ceramic matrix TiB2 platelets and TiC irregular grains were clearly refined and their volume fractions sharply decreased, as shown in Fig. 6.
In contrast, there are only a number of sub-micrometer/micro-nanometer TiB platelets, irregular TiC1-x grains and Ti phases in the intermediate of 0.2 away from the ceramic matrix, as shown in Fig. 7.
However, different from the final stage of preparing the laminated composite of TiB2-based ceramic and stainless steel, hyper-peritectic reaction takes place in the intermediate nearby the solidified ceramic due to the presence of limited Ti liquid, so a number of fine TiB platelets develop nearby the ceramic matrix.
In contrast, in the intermediate of 0.2 mm away from the ceramic matrix, the concentration gradient of B atoms sharply decreases while the one of Ti atoms increases, hypo-peritectic reaction happens in the intermediate of 0.2 mm away from the ceramic matrix due to the presence of enough Ti liquid, so there are much more TiB platelets to grow, especially there are a number of TiB solids to directly grow from the residual Ti liquid, as shown in Fig. 7 (b).