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Though a number of alloys exhibit shape memory effect, only those alloys that can produce considerable amount of strain (or) force are having great importance.
But in polycrystalline sample the [001] direction will vary from grain to grain.
Most of the researchers study single crystal Ni-Mn-Ga alloy, as they their properties are not affected by the microstructural phenomenon like the variation of crystallographic direction from grain to grain, and that they are more ductile.
These powders are mixed and grained manually at room temperature using the mortar and pestle.

Also, it can be clearly seen that the overall quality of the cladding area is good, the coating is relatively dense and homogeneous, and there exist a large number of dense elongated acicular crystals.
The microstructure of the coating is very homogeneous and has no individual grains and grain boundaries.
In the presence of the composite coatings, the atomic arrangement is out of the long-range order, which greatly limits the propagation of cracks and defects, such as the segregation in the grain boundary in the composite coating is rarely exist, forming a dense stacking and isotropic microstructure.
With the addition of the various elements, there are several strengthening mechanisms in the cladding layer, such as grain refinement, solid solution strengthening and hard particles.
Besides, the Ti and V elements play a role in the grain refinement, Ni can improve the toughness of the coatings, and the rigid element Co is added to form a solid solution to promote the wear resistance of the coating.

Instead other effects like concentration dependence of diffusion coefficients, grain boundary diffusion, stress-strain effects, spinodal decomposition of austenite and others were discussed.
The only additional effect, which has survived in textbooks up to the present, is grain boundary diffusion.
However, given the fast diffusion of carbon in both austenite and ferrite, it is unlikely that diffusion in grain boundaries is significantly higher than in the bulk.
Model description We use the multi-phase-field method [8-19] where a system of N phases or grains of one phase, but different orientation is described by a set of field variables Φi (i=1,….., N).
Due to the high computational cost of the simulations only a limited number of calculations per case were possible.

Therefore, the tensile deformation along an in-plane direction requires the compression strain along the c axis in most of grains.
They explained this phenomenon from a viewpoint of strain incompatibility between the grains with different orientations.
Koike et al. also pointed out that the anomalous twinning tends to occur more frequently in grains near (0001) [1210] rather than near (0001) [1100] [10].
However, there are number of studies indicating that the twins are frequently seen where strain localizes ([6] for example).
Zhang: Current research progress in grain refinement of cast magnesium alloys: A review article, J.

With the extension of aging time, ZnO gel with network structure will be formed after the further hydrolysis and poly-condensation of a large number of zinc acetate (Zn(CH3COO)2) molecules.
The grain size was calculated and shown in table 1.
The grain size of samples for sol aging 24 h & 48 h increased, and the grain size of samples for sol aging 72h decreased with rising annealing temperature.
The tendency about the diffraction peaks intensity and grain size revealed that the crystalline quality of samples for sol aging time 24 h & 48 h improved with rising annealing temperature, and the crystalline quality declined in regard to the samples for sol aging 72 h, which might be assigned to the excessive chemical reactions.
The grain size of the samples at different sol aging time and annealing temperature.

In metallic materials the chemical compositions as well as the microstructure, in particularly the concentration of grain boundaries and electrical conductive inclusions etc., have a significant effect on the thermoelectric behavior and therefore on the Seebeck coefficient [4, 5].
Two micro-alloyed fine grained steels of nearly the same chemical composition but from different batches are chosen to ascertain the influence of small changes of alloying elements.
Besides their chemical composition, the grain structure ascertains the thermoelectric behavior.
With progressive deformation, the grain structure is orientated uniformly in the direction of the rolling, and crushing of grains is attended (Fig. 4b).
Acknowledgments This research work was financed by the Deutsche Forschungsgemeinschaft (DFG) under the funding number HO 2165/36-2.

Since the theory was established at the beginning of 20th century, it has been extensively applied in the researches of many different areas, such as the morbidity of epidemics, the prediction of grain production, and the forecasting of precipitation as well as short-term weather.
According to the law of large numbers from probability theory, when the quantity of samples has reached to a considerable amount, the frequencies of transition between different states will be extraordinarily closed to the transition possibilities.
Increase the number of states by narrowing the interval.
Considering the insolation alters stochastically but not violently, this paper, inspired by the application of the Markov Chain in grain production [7], combining the astronomic and meteorological model and statistic regulation, presents the method for forecasting insolation value by using multiple steps Markov Chain.
[7] The Application of Weighted Markov Chain Model of Time sequence error to the prediction of grain yield state (in Chinese) Li Jing [8] Principles for Solar Thermal Applications and Computer Simulation (in Chinese) Northwestern Polytechnical University Press Hefei Zhang [9] Renewable Resources and Its Generating Technology (in Chinese) Science Press

Fig.2 Illustration of the experimental set-up Pressure Diamond segment 37.5 mm PC vs Saw blade ap A/D card Wattmeter Dynamometer Workpiece vw Fh Fv Fh Fv Fn Ft Journal Title and Volume Number (to be inserted by the publisher) 227 The morphologies of worn diamond segments were examined at regular intervals by using an optical microscope connected to a digital video system.
Therefore, good retention of the metal matrix to diamond grains, which really determines the wear performance of diamond segments, is not only associated with good bonding but also with whether the matrix and diamonds wear rates appropriately match.
As compared to the diamonds without coatings, more diamond wear flats can be seen on the worn segments containing coated diamonds (see Figs.11c and 11d) due to the difficulty of grain pull-outs.
The improved diamond protrusion as indicated in Fig.11 is also attributed to the increased bonding between the coated diamond grains and bond matrix.
Fracture with wear flat Un-coated Coated Journal Title and Volume Number (to be inserted by the publisher) 231 Since the diamonds and matrix wear rates appropriately matched in the sawing with segment S containing coated diamonds, optimal working conditions could be formed on the worn segment surfaces.

The principal cause is that the incidence of particles could happen randomly over the matrix or the reinforcement grains.
The first one had spherical grain reinforcement and the second rectangular-triangular ones.
Boundaries of the grains are clearly resolved; matrix parts and interface zones are well-defined.
Applications on integral-differential erosion wear models [Casesnoves, 2016-7, 2, 4] are feasible since the number of measurements are statistically trustworthy and consequently the hardness polynomial functions are continuous, differentiable and integrable.
Volume 2, Number 4, pp. 1-10. www.ethanpublishing.com.

Different numbers after the letter “m” show different adding amount of alloy “m”.
The number of the oxides existing in transition region must be reduced, nevertheless the separate black area in Fig. 3e will form oxides enrichment area.
Actually, these small meshes are many small grains towards different locations.
WC particles provide more cores for nucleation, thus grains is refined effectively.
(3) The WC particles play the role of the solidification nucleus of the molten steel and refine grains effectively.