Search results

It can be seen from the figures that a large number of fine cellular grains are distributed as a "fish scale" shape, which is the typical morphology of selective laser melting technology formed after the solidification of laser scanning molten pool.
The difference of cooling rate between the edge and the center of molten pool leads to the uneven distribution of these grains in the banded structure

Such a film is advantageous for sensor devices since it has a large surface/volume ratio and thus has a large number of the reaction sites on the surface.
In the previous paper, we showed that the response can be fitted by a double-exponential function of time, which indicated that the sample resistance is controlled by a Schottky barrier at the boundary between the grains [8].
Hydrogen gas is considered to remove the fixed negative charge at the surface or grain boundary by the reaction H2 + O− = H2O + e− (3) where O− is the negatively charged oxygen atom, and e− a conduction electron.

Polishing speed, depth of penetration, feed rate, wheel properties such as abrasive material and abrasive grain size, are the dominant parameters for the spherical polishing process, as shown in Fig. 1.
As mentioned, the main spherical polishing parameters having significant effects on surface roughness, are the speed of the polishing ball, abrasive material, abrasive grain size, feed, stepover distance and the depth of penetration etc.
The S/N ratio, η, is defined by the following equation [8],       −= −= ∑= n i iy n stic characteri quality square mean 1 2 10 10 1 log10) (log10η (1) iy : observations of the quality characteristic under different noise conditions n : number of experiment The optimization strategy of the smaller-the better problem is to maximize η defined by equation (1).

The Ru-RuAl eutectic phase wets the grain boundary of RuAl which usually leads to a high ductility of the material.
This may be the result either of oxide layer exfoliation or of different orientation of grains or both (Fig. 2).
Acknowledgements This research is supported by the National Program PNCD II contract number 182/2012.

Table 3 Cooling rate of specimens specimen 1 2 3 4 5 6 △t[s] 50 71 69 56 37 29 CR[℃/s] 2.801 1.972 2.029 2.295 3.784 4.375 Metallographs We take a large number of photographs of every specimen from one side to the other in 100 times magnification.
For example, changes in carbon concentration or lattice, grain refinement, and so on.
Modelling of inoculation of met allicmelts: Application to grain refinement of aluminium by Al-Ti-B.

After a number of preparations some sets of technical parameters were selected for scanning.
And the large alloy phase possibly generated across crystal grain cracks.
Fig.2 Across crystal grain cracks Fig.3 Traverse crack Fig.4 Cracks caused by gas cavities 3.3 Effects of component 3.3.1 Effects of nickel Adding Nickel into Fe-Cr-C alloy can increase plasticity of the cladding coating.

Acknowledgements The open fund of Key Laboratory of Material Corrosion and Protection of Sichuan Colleges and Universities (Project Number: 2009CL05) References [1] Tiegeng Xiang.
Effect of initial grain size on the secondary grain growth in molybdenum sheet [J].Materials Science and Engineering, 1984, 68(1):45-53

The distribution of the grain size of the powder, obtained by HRSEM (50000x) quantitative image analysis, is shown by the histogram, Fig. 1b.
(a) TEM image of ZrO2:10%Eu 3+ (b) Grain size distribution obtained by HRSEM image analysis.
The differences in the images of the polyurethane matrix and nanocomposite indicate that with the increase of an amount of nanofiller, the degree of the phase separation in these materials changes and the number and size of the hard domains increases.

The background strongly depends on defective structures, in particular grain size and dislocation density [10].
Since heat treatments at 800 °C for 8.28 x 10 4 s (23 hours) do not change the mean grain size and scarcely affect the dislocation density [5], also repeated test runs do not remarkably modify these microstructural features and, consequently, the background level.
In the samples already submitted to IF test runs part of the material has been transformed and its fraction depends on the number of runs.

A number of factors such as the deformation history, microstructure stability, corrosion, stresses, creep behaviour and composition of scale play a important role in the life extension of highresistant steels [4,5].
The critical concentration of solute metal providing the formation of a protective scale during selective oxidation decreases with decreasing alloy grain size.
It is a result of fast diffusion along the grain boundaries, dislocations, martensitic laths, etc.