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Techniques such as X-ray lithography, electroforming, micro-moulding and exciter laser ablation are used for the production of micro components out of silicon, polymer and a limited number of pure metals or binary alloys.
Typically, grain growth and densification occur during sintering, both of which affect the final properties[7].
Sintering is often devided into three stages charactered by the micro structural changes ranging from contacting particles to neck growth, pore coalescence and finally pore shrinkage and grain growth.
Each stage is progressively changed in term of neck size, pore size and grain size[17].Fig.10 shows the morphology of the samples sintered by using three schedules.

TB movement is inhibited significantly by the grain boundaries in polycrystalline materials; thus, researchers have also applied annealing for grain growth [6 - 8], compression [3, 9], and matching the grain and sample size [10] to enable high MFIS in polycrystalline Ni-Mn-Ga.
Gallium sulfate, nickel sulfate, and manganese sulfate were formed as shown in Eq. 5 - 7. 2Ga + 3H2SO4→Ga2(SO4)3+3H2↑ (5) Fig. 3: Dissolution rate of Ni-Mn-Ga denoted by the green numbers, mg/min based on the chemical composition of the etchant Ni+H2SO4 → NiSO4+H2↑(green) (6) Mn+H2SO4 → MnSO4+H2↑(yellow) (7) Copper (II) sulfate pentahydrate (CuSO4•5H2O), a bright blue crystalline solid, is a hydrate and a metal sulfate that contains copper (II) sulfate.

While it is conceded that there are a number of characterization efforts done with regards to amang originating from the Kinta Valley, work that couples the chemical and physical characterization with mineral liberation studies and mineralogical assessments are scarce.
The similar specimens were also viewed using Field Emission Scanning Electron Microscopy with Energy Dispersive X-Ray Spectroscopy (FESEM/EDX) (model Zeiss Supra 35VP-24-58), where the EDX analysis may provide ample confirmation of the mineral/grain identified under the microscope.
The brownish colour of the grains may be due to high content of iron in the sample and can be confirmed from the optical observations or XRD/XRF analyses.
In any case, this may reflect on the mineral liberation conditions with the finer particles may have better liberation due to elimination of weak planes between mineral grains.

The grain size distribution of quartz sand and FNS is shown in Fig. 1.
Grain size distribution of quartz sand and FNS.
The angular sharp edges of the FNS grains only give a small effect on flexural strength, resulting in similar flexural strength with reference mixture as mentioned above.
Acknowledgement The authors would like to thank the Vlir-Uos, Belgium for providing the financial support to this research project (The South Initiative 2020-2021) with contract number: ID2020SIN281A101.

This is attributed to changes in the material removal mechanism between the two grains.
If the rotational speed of grinding wheel is increased, ground surface roughness is improved because grain effects affecting the circumference direction of workpiece are decreased.
In general, as the grit size decreases, the number of active cutting edges per unit area on the wheel surface increases, so the spacing between active cutting points reduces.
After rough grinding at feed rates increased from 0.5mm/min to 3.0mm/min using the grinding wheel of 20µm grain size, surface roughness was badly affected.

For instance, Yanushkevich et al. [2] reported that an increase in the cold-rolling strain accelerates the recrystallization kinetics, which results in much finer recrystallized grains.
The fraction of recrystallized ferrite grains was estimated using Eq. 1 [6]: × 100 (1) where Hw is the Vickers hardness of the entire specimen, HNR is the Vickers hardness of the as-cold rolled specimen, and HR is the Vickers hardness of the fully recrystallized specimen.
Thus, it is likely that a large number of dislocations was generated by martensitic transformation during cooling after hot-rolling, thereby accelerating the progress of ferrite recrystallization of specimen M.
Weertman, Dislocations, grain size and planar faults in nanostructured copper determined by high resolution X-ray diffraction and a new procedure of peak profile analysis, Acta Mater., 46 (1998) 3693-3699

Introduction Titanium and its alloys demonstrate specific features which make them since many years promising materials for a number of application.
From the surface to the alloy bulk, following zones may be distinguished: · Small grain zone of varied thickness, with numerous crystals of titanium nitride sized up to 14 mm, and microhardness up to 2650 HV0.05, · Locally observed zone saturated with nitrogen, of average microhardness 1440 HV0.05, · Zone with dendritic needle precipitates, of thickness dominating in the whole layer, and average microhardness 850 HV0.05, · Zone possessing columnar structure of previous β phase including very small precipitates of the α' martensitic phase, of average microhardness 715 HV0.05, · Heat affected zone (transient zone) of a small thickness, with a few small grains likely a phase, of microhardness ranged between 480 HV0.05 to 370 HV0.05 at the 1.65 mm depth (hardness of a base material was 370-410 HV0.05).
Wear depth of remelted Ti alloy; results for three tests and mean value (cross line) The laser treatment of the Ti-6Al-4V alloy in cryogenic conditions results at these conditions in relatively thick and hard surface layer originated from the appearance of very small grains, nanograins and amorphous structure, and an appearance of oxydes, nitrides and oxynitrides, as shown in another research.

Experimental conditions Macro strain (µ) Experimental conditions 0 643 1251 1611 1902 2590 3173 3356 3496 Incident beam size 0.05 mm × 0.5 mm Collimator size 0.05 - 2 mm × 1.0 mm Number of measurement point 3 points (0.1 mm step) Measurement time at one condition 15 min/point (total: 45 min) Figure 2.
Some oscillated (hkl) planes correspond with any slip plane, {111}, {112}, or {123} for α-Fe or {111} for γ-Fe (see in e.g. [12]), suggesting that the formation of dislocations began on local grains which were specific planes.
Other possibilities for oscillation of the lattice strains are stress in a direction other than the loading axis, or rotation of grains by tensile loading.
This result could support the existence of the rotation of grains despite being in the elastic deformation zone.

The crushed rock layer with a specified grain size beneath the pavement layer is composed of a poorly-graded open coarse rock matrix.
The depths of the open grain crushed rock and pavement layers are H and H1.
Usually, it is assumed that local thermal equilibrium exists between the earth fill or crushed rock and the air and that Darcy’s law can be satisfied approximately as long as the Prandtl-Darcy number of crushed rock layer is larger [19].
The average grain size of crushed rock matrix is 6—8 cm.

Analysis of ZnAl type alloy microstructures with different additives has been thoroughly covered in a number of works [1-3,5-8], though less is known about the Al content in castings made of ZnAlCu after gravitational cast, and also about the influence of annealing on the morphology of the microstructure and hardness.
The usual mechanical grinding and polishing with diamond wax and polishing belt with grains 3 and 1 μm and with a very fine finish strap and OP-AN liquid suspension were used to prepare the samples for metallography.
Heat treatment eliminated the dendritic microstructure of ZnAl27Cu2 alloy, grains of light phase α and dark eutectoid composed of phases α + η and phase ε were observed, Figs. 18 and 19.
Fig. 15 Microstructure of ZnAl27Cu2 Fig. 16 Detail of phase ɛ in ZnAl27Cu2 Fig. 17 Lamellar eutectoid in detail with white grains in ZnAl27Cu2 Fig. 18 Microstructure of ZnAl27Cu2 after heat treatment Fig. 19 Microstructure of ZnAl27Cu2 after heat treatment Fig. 20 Particles based on Fe in ZnAl27Cu2 after heat treatment Fig. 21 Microstructure of ZnAl40Cu2Si2 Fig. 22 Microstructure of ZnAl40Cu2Si2 ZnAl40Cu2Si2 alloy Microstructure of the alloy with the highest Al content of 40 % alloyed with Cu and Si had dendritic morphology in the cast condition too, Fig. 21, 22.