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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.

Meanwhile, computational modelling has been introduced to predict the hot tearing, and a number of criteria had been developed [4-8].
This suggests a force relaxation taking place during the solidification due to the rearrangement of the solid grains and the remaining liquid under the imposed solidification stress.
%Al alloy (Fig. 7 (a)), the surface of hot tear is very smooth and clean with some evidence of fractured grain bridges.

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.

Typical Mechanical properties of Cast and PM TiAl alloys Rotating bending fatigue tests were conducted at both room temperature and at elevated temperature (650 oC), the number of fatigue test specimen is both 6 for two different near net shape processes (cast and powder metallurgy).
The microstructure of PM TiAl alloy is normally lamellar with uniform grains with no texture.
The grains of PM TiAl are much smaller than that of cast TiAl.

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.

Wu Zhenyu et al. [17] investigated tool wear on wt.15%SiCp/Al composite in the milling speed range of 10-180m/min with ultra-fine-grain carbide tools.
Wu Zhenyu et al. [17] reported that the number of the crushed, and the detached SiC particles increased with the increasing of cutting speed, which resulted in the increase of cutting vibration, cutting forces, cutting temperature and the value of surface roughness.
Reinforcement volume fraction, cutting speed, reinforcement particle size, cooling condition, tool material grain size, heat treatment of the matrix and tool wear were these significant factors which influenced the machined surface quality.

The process parameters are adjusted so that the deposit has a columnar grains structure perpendicular to the interface.
It has been suggested that the factors, which may influence the stabilisation, are size, valency, and concentration of solute cations and crystal structure of the solute oxides, where the valency and concentration determine the number of oxygen vacancies created by the formation of substitucional solid solutions[13].
Ta2O5 has been found to affect the phase stability and the electrical properties of ZrO2, and Nb2O5 has also been found to dramatically change the grain boundary electrical conductivity[18].

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).