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Plot of the grain size distribution for the FeMo + 1.5wt.
As regards the TiO2-bearing steel, the coarsening of the nano-pores is not evident while their increment in number is clear although far less dramatic (accounting for just a 50% increment).
Detail of SiO2 along grain boundaries in FeMo + 1.5wt.
Table 4 summarizes the mean grain size obtained through these different grain refining techniques.
SiO2 was observed both in the grain interior, in the vicinity of the grain boundary, and also at the grain boundaries and triple junctions, while TiO2 was generally only found along grain boundaries and at the triple junctions.

Humidity of a compound and optimum grain-size composition were set earlier [7].
However when using a normal grain-size of a particle have small dispersion by the sizes.
It has an adverse effect on their package, on number of contacts.
Strength of structure changes according to number of contacts between particles [7].
Therefore it is necessary to use raw mix of the certain type, allowing to receive the maximum number of contacts.

Continuity, momentum and energy equations are applied to finite number of control volumes under steady state conditions.
The unprocessed base material has an average grain size of 6 µm.
For the former, a simple linear grain growth model is used in this study, Eq.5.
(a) as-received coarse grain structure, (b) stirred zone microstructure with very fine grain size and (c) transition zone with relatively coarse grains.
However, the maximum predicted dome height is adversely affected by grain refinement.

As a result of a series of studies on the impact modifiers to change the structure and properties of steel were detected changes in the structure; in particular the number of non-metallic inclusions was reduced.Heat treatment allows improving effect of modifying the structure of steel and the items received.
The modified samples no carbides, blowholes, a decrease in the number and size of inclusions along the boundaries and inside grains, as well as visually observed a decrease in grain size.
The dependence of the grain number of modifier additives Equally significant is the amount, and hence the size of dendrites per unit area macrosections surface.
The results of calculation for the number of dendrites and equiaxedtransgranular zones show that the largest number corresponds to the addition of a modifier of 0.005%.
They are located in the grain volume, but not in the interdendritic areas as compared to the unmodified steel.

This parameter is closely related to the maximum grain depth of cut hmax.
On average, for describing the process associated with abrasive machining, the maximum depth of cut taken by a cutting grain can be expressed as [5]: s p s w max d a v v tanC 3 h ⋅      ⋅ ⋅ = θ (1) where C is the number effective on the wheel surface, θ is the semi-included angle for the undeformed chip cross-section, and θ=60º is often taken as a typical value [6].
When the grain depth of cut is below the threshold value, the material removal process is mostly ductile.
When grinding with mesh size #1200 wheel, due to the different grain protrusion of diamond grits on the wheel surface, the contact between the diamond grain and workpiece were various from each other and a fraction of the grain was engaged in creating the ductile plowing as shown in Figure 3.
The results also show that the different grain depth of cut for these materials.

CuO gives rise to a liquid phase; Sb2O3 retards the formation of liquid phase and hinders the growth of grain.
Table 1 Serial number and compositions of the SnO2 samples Serial number of samples (abbr.)
Antimony oxide hinders grains growth from the evolution of the microstructure in 0.5Cu0.1Sb and 0.5Cu0.5Sb samples.
However, copper cations rich at grain boundary control the electric conductivity of the 0.5Cu0.1Sb sample, which is the sample with very small content of Sb2O3.
The sintering behavior and the microstructural evolution of xCu samples are strongly dependent on the liquid phase characteristics and the substitution of Sn4+ by copper ion at grain boundaries.

The corresponding grain structure visualized in the polarized light after anodizing in the Barker´s reagent is in Fig. 2c.
After one-step annealing the size and shape of the grains remain unaffected, only shear bands inside the grains are missing due to recovery (Fig. 2d).
Highly elongated grains in the sheet cold rolled with 96% reduction are in Fig. 2e; the micrograph shows also centerline segregation.
Microstructure of the sheets: (a and b) intermetallic particles after cold rolling reduction 39%, grain structure after cold rolling reduction of 39% (c) and following one-step annealing (d), grain structure after cold rolling reduction of 96% (e) and following one-step annealing (f).
The plots indicate an important increase of the number of fine particles during heating to 450°C (Fig. 3a).

In addition, the content of alloying elements of Al and Zn was higher in the grain boundaries and the eutectic structure than that in the primary solid particles and in the second α-grains. 1.
Introduction Magnesium based alloy, with a number of desirable features including low density, high strength-to-weight ratio, good damping characteristic, well castability and abundant resources, has developed as one of the most popular engineering constructional materials for applications in the automotive and aeronautical industries [1-4].
The microstructure consisted of primary α grains surrounded by a eutectic mixture of α-Mg and β-Mg17Al12.
From EPMA micrographs as shown in Fig. 6d, it can be concluded that the content of alloying elements of Al and Zn was higher in the grain boundaries and the eutectic structure than that in the primary solid particles and in the second α-grains.
The mean composition of α-Mg solid solution was lower than the nominal composition of the alloy and the eutectic consisting of fine near-equiaxed secondary α-Mg grains and Mg17Al12 precipitates at the grain boundaries. [14-16] Fig. 6.

Considering the good agreement between experimental results and results calculated using the lattice diffusivity (see Fig. 4(b)), the grain size must be so large, i.e. the number of grain boundaries so small, that the amount of copper diffusing into the few grain boundaries can be neglected compared to the amount diffusing into the bulk.
As the grain size decreases, the number of grain boundaries increases and a point is reached where copper diffusion in these grain boundaries cannot be neglected.
With a continued decrease in grain size, diffusion fields normal to the grain boundary overlap.
The effective diffusivity is defined as d D DD GB LAT EFF 3 4δ += (5) with DLAT the lattice diffusivity, δ the grain boundary width, DGB the grain boundary diffusivity and d the grain size.
- Using grain boundary diffusion theory, copper diffusivities input to the model were correlated with austenite grain sizes.

The sites and length of the cracks are assigned by uniform random numbers and normal random numbers, respectively.
The large cracks in real plants may be created by the initiation of grain sized micro cracks, coalescence of cracks, and subcritical crack growth over a long term.
Because grain sized micro cracks can be initiated in grain boundaries almost perpendicular to the tensile direction, the possible number of the cracks is given by sizegrain Average area Simulated max =N (2) Step 2: The initiation time for each crack is assigned by the random number based on the exponential distribution.
The square region is 10mm×10mm, and the average grain size is 0.1mm.
Therefore, the possible number of cracks to be initiated is ten thousand.