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E.cantu-Pa.z. gave a typical classification of a parallel genetic algorithm (PGA), basically can be divided into the following three categories: Global PGA Model, Coarse-grained PGA Model and Fine-grained PGA model.
Coarse-grained parallel genetic algorithm designs 1 Coarse-grained parallel genetic algorithm model Regional Structure.
When the number of iterations of the sub-populations reaches the maximum number or all sub-processor has achieve maximum migration cycle, output the optimal solution. 2 Coarse-grained parallel genetic algorithm process The basic idea of parallel genetic algorithm is to divide a population in the serial GA into sub-populations, and each sub-population is assigned to a processor.
Eq.10 represented to ensure that the number of customers of each vehicle is less than or equal to the total number of customers.
Take the coarse-grained parallel genetic algorithm crossover probability 0.9, mutation probability of 0.04, the migration rate of 0.1, the number of sub-populations of 3 , migration cycle 25, the iterations of sub-populations of 600, and the population size is 60.

This quality index is defined as the sum over the peak sharpness of all detected peaks in a Kikuchi diagram [2] and is related to the number of lattice defects in the investigated volume.
Journal Title and Volume Number (to be inserted by the publisher) 3 Table 1.
Some <100> grains or sub-grains are then associated to a lower average SE.
The <100> oriented grains have been marked with the symbol ■.
This goes in the sense of the relative stability of the microstructure of the <100> oriented grains after the wire-drawing process or to the occurrence of dynamic recovery in these grains.

However, the layers of the 7075 alloy always exhibited smaller grain size and a larger number of secondary phase particles.
In the bands with a higher density of intermetallic particles, the grain size is smaller.
However, it should be emphasized that both alloys exhibited equiaxed grains with a similar size.
The widths of particular bands were different – the bands containing finer grains were broader on the advancing side while the bands with a greater grain size dominated on the retreating side.
The other issue is a disparity among the grain size in particular materials (bands).

According to information taken from many sources, wear leads to malfunction of the great number of machine spare parts.
It must contain solid grains uniformly distributed in elasto-plastic matrix.
Grains of solid particles that are similar size as the adhesive grains must be uniformly distributed in elasto-plastic matrix.
Adhesive bonds between those grains must be strong.
Correspondingly, compositions with high approach angles must contain less than 50% of carbide grains.

INTRODUCTION In a search for the optimal technique of manufacturing net shape components from magnesium alloys a number of novel processing methods based on semisolid concept compete with conventional, well-established technologies.
Understanding the effect of reduced processing temperature A reduction in the processing temperature influences a number of factors changing solidification characteristics and the final microstructure (Fig. 1).
The challenge is to prevent the grain coarsening during preheating to semisolid processing.
The process starts by melting of the β phase at triple junctions and selected grain boundaries followed by wetting the remaining grain boundaries by the spreading liquid.The low melting point of grain-boundary regions is due to the fact that migrating boundaries of new grains collect and drag augmented concentrations of dissolved alloying elements and the boundaries also tend to come to rest on small particles.
The experiments with a number of spray-formed alloys revealed [9] that grain coarsening increases with a higher solid fraction up to a range of 0.70-0.75, but the exact value seemed to be dependant on the alloy, and in particular, the dihedral angle between two solid grains in contact with the liquid.

In EBSD maps (Fig. 2.) of hot rolled EK2/lab strip can be seen that the equiaxed ferrite grains were randomly oriented, characteristically with high angled grain boundaries (GB >15°).
In this work high angle grain boundary (GB >15°) are thick and black, the low angle grain boundary (2°In inverse pole figures (Fig 4) it can be seen that the number of ferrite grains in which normal direction of rolling (ND) is the normal of {111} plane, and the rolling direction (RD) is parallel to the [101] direction (henceforth abbreviated as {111}[101] texture) increases till ε≈31%.
Detailed analyses of OIM maps indicate that as the fragmentation of the carbides increase, the number of randomly oriented ferrite grains increases (Fig. 4.).
The carbides were situated inside of ferrite grains.

The microstructure revealed increasingly compressed and elongated grain structure of the contributed grain flow and orientation, as the blankholder and counterpunch forces increased.
The outside diameter of the sprocket part in the experiments is 160 mm, and the number of teeth is 34.
As illustrated in Fig. 9, the mechanism of the occurrence of the elongated grain structure and the effects of the blankholder and counterpunch forces on the elongated grain structure are clarified.
Thus, the grain structure was easily elongated in the shearing zone and neighborhoods.
These compressed and elongated grain structures resulted in the increasing hardness.

The wear resistance of treated samples were significantly improved, which may be attributed to high hardness as a result of grain refinement.
The number of pulses was changed from 1 to 15.
The serial numbers and experimental parameters of the samples are listed in Table 1.
The microstructure of as received AZ91 alloy consists of primary α grains surrounded by a eutectic mixture of α and β (Mg17Al12).
The thickness of the refined surface layer increases with the electron beam current and the number of pulses.

This characteristics makes Ti and N ideal elements for controlling the austenite grain size in processes involving high temperatures, such as welding heat affected zone.
The role of TiN particles in the control of austenite grain size is well known and the mechanism by which they exert this influence can be explained and interpreted by the Zener and Gladman expressions [3,4], which relate precipitate size, precipitated fraction and austenite grain size.
A Ti/N ratio of between 1 and 3 yields good results in grain size control, especially when precipitation takes place in the solid state since finer precipitates are obtained [5-8].
The torsion magnitudes -torque and number of revolutions- have been transformed into equivalent stress and strain according to Von Mises criterion [11].
The results that have Journal Title and Volume Number (to be inserted by the publisher) 5 been obtained show that the mechanism which regulates the movement of dislocations during the hot deformation of austenite is different to that of grain boundary self-diffusion, a mechanism that regulates static recrystallisation, due not only to the different activation energy in the two phenomena but also to the different effects of Ti when precipitated or in solution.

Steel and alloys used in the manufacture of critical parts of machines and structures must have a fine-grained structure, as in this case they have a higher complex of mechanical properties compared with steels having a coarse-grained structure.
In the central part, the grains are noticeably smaller, but retain a radial direction.
On the inner side, the grains of the grains are rounded and have an equiaxial shape.
This is due to the modifying effect of the WC additive, which, being distributed in the metal, prevents the growth of grains.
Table 3 – Results of measurement of hardness [HRC] Measurement number Numbering of castings Sample 1 Sample 2 Sample 3 1 (outer edge) 32.5 33.9 37.3 2 31.9 33.7 36.1 3 (central part) 31.6 32.8 35.0 4 31.6 32.7 34.8 5 (inner edge) 31.2 32.6 34.6 Mean value 31.76 33.14 35.56 The microhardness of the samples was investigated using a micro-Vickers hardness tester.