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Results show there is a grain size reduction and refinement in the composite material through ball milling operations and along with that increasing B4C content in the composite powders make milling conditions very effective.
Increasing the sintering temperature results in a consistent grain growth along with that porosity level decreases up to a limit and then attain a steady state, the strength of the composites increases with compaction pressures but reinforcements content effects the strength of the material by losing its ductility making it brittle.
EDS elemental analysis of AA7175 alloy B4C used as reinforcement material with an average particle size of 10 microns blended with matrix AA7175 alloy varying the reinforcement composition as 2%, 4% and 6% for 1 hour by using Planetary micro mill pulverisette 7 (Fig.2) with Tungsten Carbide balls of diameter 3mm (Fig.2) and the number of balls is 98 by selecting the optimum ball to powder ratio of 10:1 at 600 rpm speed.
Hardness of the composites increases with B4C content sintering temperature shows significant grain growth and high compaction pressures helps in attaining high density of the composite. 4.
Microstructural and mechanical behaviours of the ultrafine grained AA7075/B4C composites synthesized via one-step consolidation.

Protein was thermo-decomposed at the grain boundaries and resulted in grooves.
Most aragonite preferred precipitation on the grain boundaries and some vaterite was on the grains.
Thus, aragonite nucleated at grain boundaries at the first stage.
After 24 hrs of crystallizing time, the calcite precipitated, and still there were small aragonite on the grain boundaries and grains on the other zone.
When supercooling degree increased, the number of nuclei will increase and further forming more calcites.

It has a uniform grain size, high strength and good molding performance[3], and can be work hardening and aging strengthening.
Table 1 EDS of Cu-7.5Ni-5.0Sn alloy as-cast microstructure Number Mass fraction (Wt%) Atom fraction (At%) Cu Ni Sn Cu Ni Sn A 89.13 8.02 2.85 89.73 8.74 1.53 B 57.65 17.15 25.20 64.27 20.69 15.04 C 84.09 8.52 7.39 86.45 9.48 4.07 Table 1 is the EDS result of A, B and C three points in the alloy.
The grain size of the alloy is too coarse and uneven size when the temperature reached 900℃, shown in Fig.3(c).
Rough and uneven grain will affect subsequent cold working.
The grain would be too coarse grain and the grain boundaries possibly melt if the temperature is too high during the solid solution treatment process.

After SMAT tooling on the sheets, a nano-size-grain layer with a mean size of about 50nm and an neighboring ultrafine-grain (UFG) layer with a mean size of less than 100nm form on the surface of the metal sheets with a total thickness of more than 100 µm, in which the grain size gradually increases as a function of the depth below the surface.
The number of triangular elements is 30,000, and 44,825 cohesive elements.
Energy release rate Gc of coarse-grained layer of co-rolled SMATed 304SS is obtained by Gc=(KIC2(1-μ2))/E with the fracture toughness KIC=100MPam0.5.
Cohesive strength and energy release rates of the nano-size-grain layer and ultrafine-grain are unknown and they will be defined by compare the results between the experiment and simulation.
Ritchie, A micromechanical basis for partitioning the evolution of grain bridging in brittle materials.

However, grain refining of the Mg and Sr content 319 alloys produce sounder castings with finer grain sizes.
However, the modified grain-refined alloy (GMST) revealed a greater response to ageing compared to the Sr-modified alloy (GMS).
Grain refined and Sr-modified improve to a great extent the alloy response to ageing, as shown in Figs. 2 (b, d and f).
As can be seen from Fig. 4 (m), a large number of small dimples is replacing the area that occupied by the unmodified Si flakes.
On the other hand, grain refining and Sr-modification 319 alloys produce sounder castings with finer grain sizes. 4.

In the last decade various CNTs-reinforced ceramic systems have been developed and a number of works have reported improved properties of these composite materials.
The average diameter of the smaller grains are circa 300 nm and in the case of the bigger grains are approximately 800 nm.
The structural measurements show that the silicon nitride grains are well sintered by GPS method, and no porosity can be observed between grains.
The average diameter of the Si3N4 grains is ~200 nm.
However porosity is developed at the graphene/Si3N4 grain boundary.

The grain growth and grain boundary determine the densification of SZTP system.
When the samples sintered at higher temperatures, the increase of grain size and trapped pores inside the grains could be observed.
The ceramic without Ti exhibits irregular growth of the grains, resulting in a larger number of pores.
In a word, the grain size is quite uniform.
The SZ3.9T0.1P forms smaller globose grains.

The Ni47Ti44Nb9 cold-rolled plates retain a significant number of dislocations after annealed at 350 and 400°C.
TEM and XRD observations showed that the relationship of deformation energy stored in different orientation grain was: E{110}〈001〉< E{001}〈110〉< E{112}〈uvw〉< E{111}〈112〉< E{111}〈110〉< E{110}〈110〉 [24,25]. {110}<110> orientation grains has the highest deformation stored energy, and recrystallization nucleation first appears in this type grains.
Texture is mainly decided by the orientation nucleation of recrystallization grains. {110}<110> and {332}<110> orientation grains has higher stored energy, and recrystallization nucleation but not the same orientation is happened in these grains, so the original orientation disappear after annealing. {111}<112> and {332}<113>orientation density is strengthened because{111}<112> and {332} <113> grains have high stored energy and are close to the {111} orientation, and nucleation speed and ratio is high leading to priority in situ formation of the same orientation nuclei.
Annealed at 600°C and 700°C, texture type is decided by grain growth mechanism for deformed grain fully recrystallization. {332}<113> orientation density is the highest for orientation grain in situ nucleation and growth. {111}<112> orientation has higher nucleation rate, nucleation ratio and has the advantage in the grain growth stage.
The typical b.c.c metal recrystallization texture of {111}<112> is formed by swallowing {001}<110> orientation grain.

The formation of low quantities of new alpha grains took place by cDRX by progressive lattice rotation at the prior grain boundary.
At high strain rates austenite grain refinement occurred by deformation bands below 900°C.
EBSD measurement of the steel deformed at 710°C and 3x10-4 s-1 showing the grain spread misorientation (from blue to red) and the grain (black) and subgrain (white) boundaries.
This can be due to the damage of the material (pores at the triple grain boundary)
In both cases, pores at the grain boundaries are observed Hot deformation models.

Fig. 1 illustrates schematically the cutting mechanism of an individual grain of the grinding wheel.
In transverse direction, material is squeezed to both sides of the grain, and the plastically deformed material remains at the ground surface.
The number of relevant technological parameters of the grinding process, however, is large.
On relevant parameter for the generation of compressive residual stresses is the average cutting depth of the individual grinding grain [3, 4].
The average cutting depth of individual grains is determined by the downfeed, the infeed speed, the cutting speed, the size, shape and density of the grains of the grinding wheel.