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The grain size of 0-1.5 mm was used because of the preparation of test samples for the determination of tensile properties according to the ČSN EN ISO 527-2 standards (1A and 1B specimen).
The thickness of the specimens is 4 mm and any grain size larger than 1.5 mm could result in measurement inaccuracies [3].
Both the number of pores and the size of pores increase.

The starting microstructure of the steel, comprising partially recrystallized ferrite grains with streaks of fine spherical carbide in them, is shown in Fig.1, and the steel composition listed in Table 1.
However, after etching with 2% nital, in those samples oxidized at temperatures above 800°C, the surface region in the substrate immediately under the scale appears to have more grains occupied by the Fe/Fe3C eutectoid (Fig.4), indicating that carbon was enriched in this region after heavy oxidation of the steel.
Strictly speaking, at temperatures between 600 and 660°C, according to Equation (4), there should not be a single activation energy number for the overall oxidation rate constant because the wustite-magnetite thickness ratio varied significantly within this temperature range.

Tin electrodeposition has been applied in industry as a coating on a large number of metals, particularly steel (tinplate), to impart corrosion resistance, increase appearance or improve solderability.
Thus, the morphology of the metal grains tends to grow more uniform and more compact in a magnetic field because the convection supplies sufficient metal ions to each grain during the growing process.

Introduction Reduction of the greenhouse pollution, lowering the amount of scrap produced during the fabrication of components and diminishing the number of processing steps are important aspects currently taken into account by the manufacturing sector [1].
Optical micrographs of the Ti-5.41Fe/Ni (left) and Ti-7.57Fe/Ni (right) alloys, respectively, sintered at: a) and b) 1200ºC and c) and d) 1300ºC From the micrographs shown in Fig. 3 it can be seen that the microstructure of the sintered Ti-5.41Fe/Ni and Ti-7.57Fe/Ni alloys is compositionally homogeneous and it is composed of alpha grains and α+β lamellae, due to the stabilising effect of the alloying elements (i.e.
From the micrographs of Fig. 3 it can also be noticed that the residual porosity left from the sintering process is mainly located at the grain boundaries and the pores are spherical in shape.

The effect of cooling rate on the structural features of the 3XX series of aluminum alloys such as grain size, Secondary Dendrite Arm Spacing (SDAS), eutectic silicon structure and the morphology of iron and manganese phases has been investigated by many authors [1, 2] and correlated with thermal analysis characteristic parameters [1, 2, 5-9].
The general consensus from the previous work is that an increased cooling rate results in refined grain size, modified silicon particles, and a decrease in the SDAS [1, 2, 5].
It appears that silicon does not substantially influence the shape and number of copper enriched eutectic peaks.

In addition, we noted that the grain sizes ranging between 50 and 500 µm and the texture is orientated along the rolling direction.
The diffractions conditions are summarized in Table 2: Table 2: Diffraction condition using Set-X diffractometer: Cathode Cr Filter Collimator Plane {hkl} Number of Y angle Y step Acquisition time (s) lka=0.292 nm V 1.5 mm {311} 15 +/-5 100 s Modelling of the laser shock peening process The Finite element method (FEM) was first introduced by Braisted and Brockman [1] to investigate the residual stress field induced by LSP.
In the future work, the validity of this 3D model, should be confirmed on another Al alloy with better XRD behaviour (smaller grains, less texture).

A number of assessment methods were employed, including resistance drilling, to identify and quantify the extent of deterioration and potential impact on structural capacity.
Vertical side posts typically are set in notches in the top face of the sills, with a gap left so that the longitudinal wall planks can be nailed into the side grain of the floor planks.
Knots and slope of grain tend to be the grade-limiting defect for lumber in older structures, and nearly all of the structural lumber and timbers used in the construction of the two trams contained large knots and could not be assigned an overall high structural grade.

Meanwhile small austenitic grain size results in large number of high angle boundaries in the matrix which also can prevent the microcrack propagating. 20um Fig. 1.
At the same time through heat transferring and electromagnetic field migrating into the interior area, surface overheating phenomenon that results in the formation of coarse austenite grains can be avoided and temperature difference between the surface and the interior area is reduced.

According to the machining accuracy requirement, a spherical electroplated diamond grinding wheel, Ø50mm in diameter and 60# of grain size, is adopted.
If the stiffness permits, a large cutting depth is suggested to diminish number of passes and to improve process efficiency.
As the rotational speed of workpiece increases, the cutting thickness of each abrasive grain on the wheel increases correspondingly, and so does the grinding force [7].

But a few number of studies in particulate composites have been undertaken with particles and particle size distribution [6] .
Table 1 The physical properties of graphite blocks Samples Mean particle size of NG /(μm) Density /(g·cm-3 ) Tensile strength /MPa Bending strength /MPa Electrical resistivity /(μΩ·m) thermal conductivity /(W/m·K) ∥ ⊥ ∥ ⊥ NM-1 817 1.863 3.895 22.267 8.90 2.67 30.4 411.9 NM-2 425 1.909 6.807 26.712 7.23 2.58 50.2 498.2 NM-3 290 1.876 5.074 21.097 10.37 2.92 43.5 473.1 NM-4 198 1.870 4.593 19.269 10.93 3.47 31.4 452.9 NM-5 156 1.845 4.335 14.803 11.51 4.04 29.3 343.5 ∥ Parallel to the direction of pressure ，⊥Perpendicular to the direction of pressure Fig. 1 Typical PLM micrographs of graphite block Fig. 2 FESEM images of the fracture surface of graphite materials Electrical properties of composites The resistivity of graphite/mesophase pitch composites is affected by many factors, the main two of them are scattering of graphite grain boundary and concentration of carriers.
The scattering of graphite grain boundary will be narrowed as the graphitization degree of several samples increases, the concentration of carriers will be increased as the graphitization degree of several samples increases.