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Also, electrical resistivity is limited to values greater than around 15mΩ.cm to limit stress and number of defects during growth and cooling.
Two other cases are explored, one with a texture with predominantly fine grain mixed with coarse grain, and the other with texture with a majority of coarse grains mixed with a fine texture of small grains.
One can observe two grain size populations: the fine grains have a diameter between 1μm and 10μm, while coarser grain populations have a conical shape whose diameter can increase up to 50μm.
As the large grains remain a minority in the texture, the average grain size stabilises rapidly.
We observe very large grains of conical shape with diameters that can reach up to 100μm, and in a minor proportion few small grains of size less than 10μm.

Also with the initiation of the plastic deformation there is an ample increase in the number of dislocations due to the formation of Cottrell atmosphere.
Larger grains grow at the expense of the smaller ones.
Grain growth as well the annealing time to start grain growth after recrystallization is strongly temperature dependent.
Each curve belongs to a different deformation degree (with increasing line numbers the deformation degree decreases - L1 with the highest deformation degree up to L18 for the lowest, see Fig. 2).
Micrographs show the formation of more globular grains.

Ceramic bodies manufactured by uniaxial pressure followed by cold isostatic press have a 97% density and submicron grain size.
Today, BPs are the drugs of choice for a number of diseases characterized by an excessive osteoclastic bone resorption [2] Bisphosphonates (BPs) are stable pyrophosphate analogous characterized by a P-C-P backbone structure and two phosphonic acid groups bonded to the same central carbon.
The explanation is based on the decrease movement of fluoride and hydroxyl ions that lead to lower densification and grain growth.
The obtained density of the bodies is 97% of the theoretical one and the grain sizes are always under 1 micron as can be observed in figure 2 left, thus an excessive grain growth has been successfully avoided while density has reached the necessary threshold.
SEM picture displayed in figure 2 right shows the presence of grains of around 1 micron on the surface of the ceramic.

In particular, following to grain refinement with clear improvements for applications in nuclear applications [11-15].
This is achievable following an hardenability improvement after austenite grain size growth.
A strong effect of reheating temperature on austenite grain growth is detected.
The effect of austenite grain size growth following on CVN is reported in Table 3.
Harries, ASTM Stock number: Mono 3.

As the doping levels increased, the average grain size of the films decreased from 10 to 2µm.
The SEM observations indicated that average grains size decreased from 10 to 2µm as the boron doping concentration increased.
For all doping levels films, the SEM showed grain of 3-5µm average size, which decreased when the doping level increased.
When the boron concentration was appropriate, the doping boron atoms formed clusters at the grain boundaries to promote a plastic relaxation [6].
The grains size of diamond films decreased significantly when the boron concentration increased.

Note that it is assumed that the nucleus has coherent interfaces with both austenite grains, which implicitly assumes a special crystallographic orientation relationship between the parent austenite grains forming the grain boundary at which the ferrite grain nucleates.
In addition, ferrite grains were also found to nucleate on other high angle grain boundaries.
An orientation relationship (OR) has been observed between 84% of the total number of ferrite grains and the surrounding austenite grains.
The other condition of the pillbox nucleation theory is that ferrite grains only nucleate on grain boundaries representing a special relation between the austenite grains.
Of all ferrite grains, 14.8% were observed within an austenite grain, suggesting homogeneous nucleation.

Microstructure control is therefore essential for any processing activity, especially for high quality metal castings with fine grains, homogeneous chemical composition and net-shape forming.
Two processing routes have been developed to produce semisolid metal castings consisting of globular grains.
Electromagnetic stirring (EMS) is the most popular method to refine grains and produce semisolid billets, but the crystals are seemly more to be disfigured dendrites[6].
In Fig.4, samples microstructures is made up of globular primary α-Mg grains(bright part in picture), and eutectic organization comprising of α-Mg solid solution and Mg17Al12 (dim part ).
With the aim to analyze the factors affecting solid volume fraction, the number of primary particles per unit area is selected to represent the density of primary particles because of randomly observed area.

These lines represent regions with higher atomic number (Ti and/or Ag) and match the position of the Ti layers deposited at the beginning and end of the multilayer, as represented in the TEM image of Fig. 1.
In the interfacial region, grain size varies from 60 to 600nm.
The Ti and Ag enriched grains formed along the center and rims of the former multilayers, present a composition close to the α2-Ti3Al phase.
The grain size of the interface when bonding is performed at 1000ºC with a Ti/Al multilayer is somewhat smaller, ranging from 50 to 300nm [4].
When Ag doped multilayers are used, γ-TiAl grain growth is favored probably due to higher grain growth kinetics and to a lower temperature of the transformation Ti+Al → γ-TiAl.

A deformed layer is detected by SEM with grains orientation along the feed direction from the sub-surface microstructure.
CVD Ti(C, N)-Al2O3 coated carbide inserts (XOMX090308TR-M08, MP2500) mounted on a 25 mm diameter tool holder (Catalog number: R217.69- 2525.0-09-3AN) made by SECO Inc. were utilized in the down milling tests.
Ti-6Al-4V alloy is a two-phase (α + β) titanium alloy, composed of equiaxed Ti α grains (hcp) surrounded by Ti β grains (fcc), as can be seen in the typical microstructure shown in Fig. 1 (dark grains correspond to Ti α and light grains to β phase).
The deformed layer exhibits a thermal softening and promotes the microstructure and grains orientation to follow the feed direction.
To determine the nature of the highly deformed grains inside the sub-surface needs to be quantitatively investigated in the future.

After dried and sieved through a 120-mesh sieve, the mixture was placed into a graphite reactor with a number of small holes on the wall to allow a controlled gas exchange between the reactor chamber and the surrounding atmosphere.
SEM micrographs of (a) crack deflection, (b) crack branching and (c) grain fracture.
The crack propagation path was increased and more fracture energy was consumed when the crack was deflected by the TaC grains.
It was seen that the grain size of Al2O3 increased severely during the preparation process.
Additionally, the density of the monolithic Al2O3 was relatively low and pores were distributed both in the Al2O3 grains and at the grain boundaries.