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In the course of this evolution, the morphology of the tungsten phase changes constantly both in grain shape and grain size.
In Fig 3 (b) the grain size increases notably as the amount of tungsten increases and significant grain shape accommodation occurs.
It can be seen from Table 1 that, as the amount of tungsten increases, the volume fraction of the tungsten phase increases and this not only changes the density of the alloy but also influences several microstructural parameters such as the shape and size of the tungsten grain, contiguity (the fraction of the internal surface area of a phase shared with grains of the same phase in a two-phase microstructure), connectivity (the number of solid-solid contacts per grain) etc.
According to the grain size data in Table 2, the mean grain size is slightly less for the alloy containing Co than for that containing Fe.
The alloying elements and composition influence the grain growth.

Wear particles in the oil pipeline carry a large number of engine status information, so monitor the abrasive grains carrying plenty of information for aviation engine operating conditions, and then to provide a reliable basis for fault diagnosis and early warning of accidents, and to improve aircraft safety and economic benefits [1-3].
The dual coil structure can effectively detect the copper grains larger than 500μm and more than 100μm iron grains [5-6].
Monitoring small abrasive grains from tens to hundreds of microns is difficult, as the small inductance changes, it’s wise to monitor the amount of voltage change caused by the rate of change of inductance to achieve monitoring of the abrasive grains.
By no grits, two excitation coils flow number equal and reversed current, whose magnetic field in the region of the induction coil offset each other, so the output voltage is zero.
A large number of simulation data shows that, in this model, when the imaginary part of induced voltage exceeds 10-6, big grits will appear.

The Al4Sr intermetallic compound is observed at grain boundaries When Sr was added.
The additions of strontium combined with calcium are very effective on decrease grain size of Mg cast alloys.
%Ca alloy, in which three different morphology intermediate phases (gray laminar eutectic, thin bar eutectic and extra block eutectic) appeared at the grain boundaries and most of Al and Ca elements congregate at grain boundaries.
Generally, the refine effect depends on three factors according to the classic solidification theory: the effective number of potential crystal nucleus in the melt, nucleation ratio and growth rate [9].
In other words, the effective number of potential crystal nucleus in the melt will increase with the alloy element addition, which can refine the microstructure of alloys.

The evolution of mechanical properties and microstructure in dependence on number of passes is also discussed.
Although relatively large deformation can be arrived, in fact the end parts of strip have to be prepared each time after roll-bonding and then, with increasing number of cycles, the length of roll-bonded strip decreases.
Material and experimental technique The experiments were carried out on aluminium Al 99.8 %, annealed 0.5 h at 400 oC, with initial grain size d = 20- 30 µm [5].
The temperature of heating and number of passes are indicated in sample column i.e.
During ARB processing up to ε = 8 of Al AA1100, the grain size below 0.5 µm was observed [8].

The ODF intensity of copper augments proportionally to the strain amplitude because, as deformation proceeds, an increasing number of grains reach the stable lattice orientation.
Plastic strains vary from one grain to the other, depending on the local neighbourhood.
Local heterogeneity of strain is properly predicted if each grain is represented by a large number of finite elements.
One of these grains has the copper orientation.
The copper grain alone totals 3426 integration points.

Theory During deposition, a number of nuclei get created.
In this case, the number of nucleation centers in each island becomes smaller, until eventually there is only one ‘active’ nucleation center.
At low temperature, the grain growth rate is quite small, but even at 630 °C, the resulting grain should grow to be 500-800Å[6], which is sufficient to fully crystallize the island.
Clearly, the smaller island has a single grain, while the larger island has 4 grains.
The next step was to take EXAFS data which averages the crystallinity level over many islands, combining the grain size information with grain quality into a ‘long range order’ parameter.

Results and discussion A film that is attached to a substrate and subjected to a tensile stress may fail in a number of ways.
A number of cracks may propagate when the stress reaches this critical value.
The occurrence of these serrations may be associated with crack propagation and the Ni3Ti grain size.
Therefore, in the film the transformation of each grain can occur easily and independently of the other grains.
This leads to abrupt transformation of conveniently oriented grains. 4.

The processing and properties of ceramic-metal composites with an interpenetrating microstructure have been reported in a number of papers [1-4].
SEM investigations in back-scattered electron mode (BSE), which makes it possible to observe the contrast associated with the average Z number, showed that the surfaces of the alumina grains were uniformly coated with a thin layer of Ni-P alloy (Fig.1a).
Further increase of the temperature to 1000o C did not change this grain size.
This indicates the continuity of the Ni grains.
Applying high pressure uniaxial pressing causes densification of coated alumina grains and reduces the number and size of the pores (Fig.5b).

Average grain size increases as the annealing temperature increases, leading to an in-homogeneous grain size distribution and to a hardness loss of about 20 HV.
Grain size distribution obtained from the image analysis of Fig. 4.
Average size 0.23 mm and standard deviation 0.12 mm (number of considered grains: 1000).
Furthermore, the obtained microstructure shows sub-micrometric grains with a grain size distribution with an average of 0.23 mm and a standard deviation of 0.12 mm.
Raabe, Abnormal grain growth in Eurofer-97 steel in the ferrite phase field, Journal of Nuclear Materials 485 (2017) 23-38

Based the knowledge of materialogy, it has been confirmed that the main mechanism of metal plastic deformation is the slipping of atomic close-packed planes caused by large number of dislocations.
A large number of slip-band traces can be observed in the specimen surface when the specimen is in the plastic state under loading, and the slip-band traces usually show a certain regular pattern.
In the polycrystalline model, the grains shape and orientation are generated randomly.
The model contains 100 grains and it is assumed that every grain has the same anisotropy (but different orientation), has no thickness of grains boundary, no micro-holes and micro-cracks.
The difference of the slip-bands in grains is mainly brought about by the difference of the initial orientation in the grains and the rotation of the crystal lattice in the tension process.