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The electrolytic copper of commercial grade M1k (99.95 wt. % Cu; 0.02 wt. % O) with a coarse-grained structure was used as a control sample.
The submicrocrystalline samples (smc) with an average grain size of 0.25 mm were obtained after such a treatment.
To obtain another structure type with grain size of 2–3 mm (mc), the smc-samples were annealed at 300 °C in argon atmosphere.
The fine Cu powder consisted of 0.15–4 mm particles of bimodal size distribution with the average number maxima dmax, 1=0.3 mm and dmax, 2=2 mm.
This might be one of the reasons for the difference in the properties of fine-grained materials from coarse-grained ones.

After machining, samples of 5x5 mm were sectioned by wire-EDM, then polished and etched for 35 seconds using Kalling’s reagent (number 2) to observe microstructural changes (affected layer and grain size) using a light optical microscope (1000X).
Affected Layer and Grain Size.
Grain Size and Affected Layer.
Grain size on the bulk material Grain size on the bulk material (a) (b) Figure 6: Grain size evolution from the machined surface to the bulk material: (a) different cutting speeds for a fixed feed rate of 0.05 mm/rev; (b) different feed rates at 70 m/min as cutting speed.
[4] WASPALOY, Special Metals Corporation, Publication Number SMC-011(2004) 1-3

For the course-crystalline (CC) and microcrystalline (MC) alloys increase of strength leads to decrease in room temperature plasticity that can be connected with a number of the microstructure changes - grain refinement, ageing, formation of solid solutions, increase of crystal defects density.
There is a high dislocation density within the grains and on the grain boundaries of ECAP sample (Fig.1a) whereas EPR sample grains have no practically lattice defects (Fig.1b).
On the contrary the grains of ECAP + EPR sample have many thin microtwins of B19'-phase (Fig.1c).
Note that EPR technique transformed CC and SMC structures to NC structures with close grain size.
The jump amplitude dependence on current density (Fig.4а), pulse duration (Fig.4б) and pulse number (Fig.4d) is clear because of increase of the parameters leads to rise in sample temperature and accordingly, to volume of the transformed phase.

The Nisa Granite is a very coarse-grained porphyritic, two-mica monzogranite to syenogranite [4].
In the study area there are the fine-grained biotite granodiorite to monzogranite, which is the granite SPI and the medium-to fine-grained muscovite>biotite syenogranite called the “Gáfete granite”.
Regarding the number of phenocrysts per unit area along the three outcrops of granite SPI, there are no significant differences and the average number of outlier phenocrysts per dm2 equals 3.8 in total set of points, with a minimum value of 1.4 and 6.0 maximum.
Ff-fracturing frequency, μA-arithmetic mean, sd-standard deviation, CV-coefficient of variation, Med-median, Min–minimum, Max-maximum, n-number of sub-parallel joint spacing considered.
(Continued) The drill core SFB1 displays a fine-grained granite.

Fig.8 The equivalent radius of processing Fig.9 Planting density of abrasive on point on the surface roughness the surface roughness Particle density determines the number of grains per unit area.
Density is larger, the number of grains per unit area of more, accordingly, the smaller the distance between adjacent abrasive.
The contour of the abrasive grains and grinding depth are the key factors.
The effect of size of abrasive grains on surface roughness is also very significant.
(3) Taking the smallest grinding depth in the finishing stages if possible and increasing the number of finishing.

Damage accumulation is dominated by microstructure related slip localization, grain morphology and microstructural ‘flaws’.
The average grain size for both heat treatment conditions is 60 mm.
Due to this intersection of slip bands the mean free path for dislocation slip is significantly reduced resulting in an increased cyclic strength at low number of loading cycles.
As can be seen in the TEM micrograph depicted in the center of Fig. 4, VHCF loading in the peak-aged condition results in the formation of isolated slip bands in favorably oriented grains which pile up at the grain boundary.
However, latest investigations on the importance of grain morphology on VHCF behavior of Nimonic 80A proved that the aforementioned mechanisms are affected by the misorientation between neighboring grains.

Aluminum is one of abundant resources and exhibits good specific strength with a number of alloying elements.
Furthermore, the α-Al grains become fine and spheroidized due to the recrystallization and deduction of interfacial energy between the α-Al grains and liquid phase.
When the alloy is solution treated, the crystal orientations of the fine dendritic α-Al grains located inside the FLP regions change to those of the near big α-Al grains (Fig. 9(b)).
Initially, the fine dendritic α-Al grains have various crystal orientations in the FLP regions (Fig. 10(a)), then the crystal orientations of the fine dendritic α-Al grains in the FLP regions change to those of the near big α-Al grains during the solution treatment (Fig. 10(b)).
(3) The Fe-IMCs are incorporated inside the α-Al grains by the extinction of the FLP regions during the solution treatment and are surrounded by the highly ductile α-Al grains.

From the analysis of the simulation results, a conclusion can be drawn that when conveying grain materials, horizontal single head screw conveyor should set an appropriate fill level and screw rotational speed according to the property of grain materials, to make the horizontal screw conveyor with a high transmission efficiency and low energy consumption.
According to the size of the grain quality be colouring, small quality grain for green, massive particles in red.
The granular flow state in horizontal screw conveyor can also use the number of the detection method to quantitatively measure the mass flow rate of the particles.
Mass flow rate, refers to in the unit time by the sum of of grain quality of a plane perpendicular to the screw shaft, this plane is usually located between two boundaries.
Show that under a certain filling rate, grain average total energy loss decreases with increasing speed, and reduce amplitude is obvious.

The grain to which the cell belongs.
The growth length, , for each grain boundary cell, i.
The driving force for the formation of a phase from the g phase is calculated by [7] (3) where m is the number of components in the system, is the fraction of the element i in a phase, and are the chemical potentials of the element i in g- and a-phase respectively.
All nuclei are set at the austenite grain boundaries.
Acknowledgement This research was carried out under the project number MC5.06257 in the framework of the Research Program of the Materials innovation institute M2i (www.m2i.nl).

Surface observation results show that the conversion coating presents in crystal feature, and the coating containning Ca was uneven with large grains and small grains.
To solve the pollution problem, a number of conversion coatings bath that are chromate free have been developed during these years, which including phosphate bath [6-8], rare-earth bath[9], and phytic acid bath[10].
For the conversion coating formed in the bath containning Ca2+ compound, the surface morphology is uneven with large crystal grain and small crystal grain.
No obvious holl appears among the grains, and the crystal grain were accumulate compactly presented in Fig.1(a).
The crystal grain is more uniform compared with the coating containning calcium.