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The microstructure of the material evolved during the process vary from columnar grain along the thermal gradient in the melt pool to fine equiaxed grains.
In their study, the number of Si particles were observed to have decreased with increasing solution temperature.
Material and Process Average Grain Size (μm) Hv0.05 LBPF Al [1] 6.0 ± 2 127 ± 1 FSPed Al 2.57 ± 1 64 ± 1 For specimens that underwent FSP, fine equiaxed grains were observed with significant grain refinements.
Recrystallisation and recovery of the material could have led to an increase in the number of sub-grain boundaries as observed in the EBSD images (Figure 3).
Material and Process Mean grain Misorientation Fraction of high-angle grain boundaries (>15°) Fraction of low angle grain boundaries (<=15°) Number of samples (1-5°) (0-15°) LBPF Al [1] 7.07 0.14 0.83 0.86 99709 FSPed Al 15.10 0.34 0.55 0.66 120740 Microhardness.

At room temperature the alloys (particularly Al-Mn) exhibit significant grain refinement by grain fragmentation leading to "grain sizes" of less than 10µm.
After multiple forging to strains of order 3, both EBSD and X-ray diffraction indicated the development of a well-defined crystallographic texture of which an example is given by the pole figures of Fig. 3 (composite Al-Mn sample to cover a large number of grains).
Over the length scales of 100-200µm, grains are seen to develop by fusion of several, previously separate, grains.
The difficulties of quantitatively characterizing as-deformed grain sizes in large-grained material are well known.
At room temperature the alloys (particularly Al-Mn) exhibit significant grain refinement by grain fragmentation leading to "grain sizes" of less than 10µm.

In order to solve the problem of the toughness with high heat input, a number of reasonable solutions have been put forward.
The total number of inclusions is the largest in the Ti-0.032%mass sample but the number is the smallest in the Ti-0.048%mass sample, the value is 3186 and 1835 respectively.
Table 3 Grain size statistics Sample Count Number[mm2] Deq [µm] B1 393 6653 13.8 B2 544 9214 11.8 B3 419 7098 13.4 B4 504 8545 12.2 B5 299 5068 15.9 Fig. 4 Relationship between Inclusion density and grain density In these five samples, the average equivalent diameter reaches the minimum 11.8 µm and the grain density reaches 9214 per square millimeter when Ti content is 0.032%.
The grain growing rate caused by grain boundary curvature can be counteracted by particles’ pinning in grain boundary [6], so the grain can be refined by appropriating inclusions around the grain boundary.
So the main grain equivalent diameter is smallest in B2 sample.

Macrostructure in the transverse (a), longitudinal (b) section of the tube, lining-out and Vickers hardness impressions (c) (without magnification) Analysis of the macrostructure showed that it is homogeneous in both the transverse and longitudinal section (Fig. 1, a, b) and has a 1-2 grain size number according to the grain size scale of the macrostructure of titanium alloys [15].
In these areas, grains elongated along the extrusion direction with 4th elongation scale number according to [8].
At the same time, the presence of a small number of elongated grains indicates that recrystallization processes are not fully completed.
This structure refers mainly to 2-3d structure scale number, according to the scale of microstructures of α-alloys [12].
This led to the formation of a more homogeneous and fine-grained structure with 1-2 and 2-3 structure scale number according to the scales of macro- and microstructures of titanium alloys, a two-component tangential texture (0001)TD<100>ED and (0001)TD<110>ED and hardness – 155 HV.

As a consequence, two fully-recrystallized material states with different grain size were obtained: fine-grained with ~10 μm average grain size (Fig. 4a) and coarse-grained with ~200 μm average grain size (Fig. 4b).
Microstructure of CuZn10, a) fine-grained alloy with ~10 μm average grain size, b) coarse-grained alloy with ~200 μm average grain size a) b) c) Fig. 5.
Upon the first minutes of the test prominent traces of plastic strain, grains uplifting and cracking along grain boundaries are visible (Fig.8 a-b).
A surface state of the CuZn10 after cold rolling and annealing at 750 ºC (a grain size of 200 µm), a),b) plastic deformation effects, c), d) the uplifting of grain boundaries zones, e), f) cavities and craters n the sample surface Additionally, results of the SEM microscopic observations revealed a large number of shear bands located near grain boundaries.
A large number of shear bands observed on surface of each sample indicate on a fatigue character of cavitational destruction. 3.

The topography of the tile was measured before and after the polishing process with particularly grit number.
The results show the evolution of roughness and gloss for each load as a function of abrasive grit number and polishing time, as well as the material removal rate for each grit number and load.
Except of the finest grain size (Lux), which is resin bonded, all these segments are made from silicon carbide grains embedded in Sorel cement matrix.
The gloss graphs are plotted as function of used abrasives and number of passages.
For fine grain sizes the protrusion of the grain is probably smaller than the hcu,crit, and in this case even higher loads cannot force the grains to penetrate the ceramic deeper than hcu,crit , so that the ductile-mode will be kept.

The effect of grain size on the semiconductor properties are in agreement with experimental and theoretical data.
The grains show complete coverage and small size as shown in Figure 2b.
The size difference of each grain is due to irregular growth rate.
The orientation of grain growth is also irregular as can be noticed from the specific decrease of grain size at different areas of the substrate.
Acknowledgments This work has been achieved using FRGS grants numbered: 9003-00249 & 9003-00255. 

L0 is the initial grain size.
L is grain size.
N is the sites number of the simulation domain. n is the solid-phase site number around one specific site.
The attempted N (total site number in the simulation system) times is regarded as one Monte Carlo Step (MCS).
The simulation time is expressed in term of the number of Monte Carlo Steps (MCS).

Continuity, momentum and energy equations are applied to finite number of control volumes under steady state conditions as shown in ref [8].
The unprocessed base material was assumed to have grain size of about 50 µm.
The estimated grain size distributions for the two cases are shown in Fig.4.
In both cases the finest grains are located around the pin zone on the AS.
Fig.4: Grain size distribution in processed region for (a) conventional tool vs.

In order to optimize performance in use, an austenitic grain size of 5 or finer is now expected in most cases, with a maximum of 10 percent of individual grains of sizes 3 and 4 partially permissible [2].
This requirement means that fine grained steels with appropriate fine grain stability have to be used [3].
Table 1: Chemical composition of investigated case hardening steels, mass contents in % For heat B, which largely complies with requirements at that time except as regards titanium content, it was shown in numerous grain growth trials that fine grain stability can be reliably achieved up to 1050 °C with a holding time of 25 hours, provided that the tolerance range with 5 percent of grains with the ASTM number 3 and 4 can be exploited.
Table 2 summarizes the coarse grain fractions observed, i.e. grains with a coarseness of ASTM number 4 and coarser.
Table 2: Comparison of grain growth behaviour of heats A (conventional case hardening steel) and B (microalloy case hardening steel); the fraction of grains with an ASTM grain number of 4 or coarser is shown in % Heats A and B are identical in terms of their production paths and the dimensions produced as forged steel bar, so that the alloy typical fine grain stability can be significantly increased in this case by the microalloying elements, both in laboratory and industrially produced case hardening steels.