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The d-value of acidified Stellerite doesn’t change much (Fig.3), the number and position of the characteristic spectral line almost keep unchanged.
At last, nanometer particles polymerize and grow into nanometer grain and have a further transformation to micron grain.

All coatings were found to be fine grained (smaller than 0.17 micrometers), had less than 1% porosity and with the coatings being primarily WC with a small amorphous content present, ascribed to being metallic Co.
Notwithstanding each measurement point having an individual accuracy of better than 20 mircostrain the anomalous scatter between data points is attributed to the smallness of the gauge volume employed which is susceptible to grain size, systematic errors and orientation effects [5].
residual stress values determined in the substrates and HVOF coatings using XRD and SR techniques Material CTE [10-6/K] Reflection DEC [TPa-1] Residual stress in grit-blast substrates [ MPa ] Residual stress in as-coated coatings [ MPa ] S1 ½S2 XRD SR XRD SR WC WC-17Co 2 WC (101) -0.321 1.707 ---- ---- ---- ---- Aluminium 23 Al (311) -5.05 19.462 -160 ± 10 -200 ± 25 -16 ± 17 -160 ± 50 Brass Cu63/Zn37 19 Cu (311) -2.902 11.106 -123 ± 10 -303 ± 25 -54 ± 28 -40 ± 25 304L Stainless steel Fe/Cr29/Ni16/C6 17 Fe (311) -1.598 7.034 -159 ± 36 -458 ± 25 25 ± 19 22 ± 50 Mild steel SABS1431 grade 300WA 12 Fe (211) -1.26 5.72 -172 ± 23 -441 ± 25 31 ± 19 60 ± 50 Super invar Fe64 / Ni 36 ≤ 1 Ni (200) -1.910 7.539 -251 ± 10 -695 ± 25 74 ± 31 288 ± 25 To quantify the respective residual stress contributions associated with the two dominant processing steps, i.e. grit-blast and as-coated condition, the plastic depth resolved strain profiles (eigenstrains) [6] are considered in Fig. 4 for a number

., since the fitting of the model to the experimental data requires a large number of parameters), or whether a technique is entirely standard-less.
Such analytical works helped to understand the crystallinity, compositional structure and defects of polycrystalline CIS-based absorbers especially on grain structure, grain boundary, depth profile in the compositional grading, defect chemistry, and so on.

For a number of reasons, so far the application of the MIG method in welding of thin-walled elements made of high-strength plastic-worked and precipitation-hardened aluminium alloys has not proved fully satisfactory; this being in particular due to significant porosity (esp. 2xxx-series alloys) and too much heat supplied to metal, which, in turn, resulted in a high decrease in mechanical properties in the fusion zone (caused by a loss of advantageous output structure of alloy following precipitation hardening) as well as susceptibility to hot cracking (formation of low-melting eutectics).
Both filler metals contain zirconium stabilising the structure and preventing grain growth.
Only in case of the metallographic specimens of the joints made of EN AW 6082 alloy by means of the MIG-Pulse method it was possible to detect micro-cracks along the grain boundary.

The parameters mainly influencing this process are the laser beam diameter, the laser power and the number of repetitions [8].
Due to the fact that the individual grains have different orientations, they react differently to the remelting process.
The varying deformation of neighbouring grains forms a step structure [18].

Fig. 2 The curve of tensile strain Fig. 3 Iron density change versus temperature [8] The tensile stress created by stretching the material under the surface of grains, thus reducing the life of the material as well as deterioration of the mechanical properties.
When compressive stress on grain pressure is applied by changing their shape and causes their strength and better mechanical properties - thereby increasing longevity [2,11-13].
(8) Fig.6 Graphical dependence of residual stress on depth of cut Conclusion Creation of equations representing the influence of cutting parameters on the formation and size of residual stresses was carried out on the basis of verification values, which is considered to be sufficiently accurate values, but when watching various statistical parameters were set relatively small number, which is the extension of the experiment followed a recommendation by mutual combination of cutting parameters for improved and more accurate identification of traces of residual stresses in the material.

During the welding process, reinforcement elements can create a number of problems in the process.
SEM (scanning electron microscope) analysis of the AA2124/SiC/25p-T4 MMC showing: (a) base MMC, (b) weld zone [2] Regarding the microstructure of the composite materials with metallic matrix the following can be said: a better homogenization of the initial distribution of abrasive particles occurs, irrespective of rotational speed of particles type in FSW zone [6], [1], [2], [7], [14], particles were distributed more homogeneously in the WZ compared to those in the BM [7], the abrasive effect of the pin on the ceramic reinforcement led to a significant reduction of the size particles to the base MMC [12], [2], [3], [10] and grain refinement of the matrix aluminium alloy was observed [12].
- for AA6061/Al2O3 and AA6060/ B4C hardness always increased from the base material to the FSW zones, due to refining effect of the grain sizes of aluminum alloy and their embedding in the soft matrix, produced by severe wear and breakage of the reinforcement particles induced by the tool.[10], [12], [13].

This solid-state reaction depends on large number of parameters such as particle size and chemical analyses of raw materials, type of atmosphere, types and the amounts of mineralizers and sintering aids [4-6].
Also in this condition grain growth and intergranular porosity have been detected [9].
Microchemical analysis of grains by SEM+EDX in different zones of the sample was shown that spinel was completely formed.

Therefore, possible grain boundary effects have not been studied.
To establish an influence of grain boundaries on the elastic and inelastic properties, it was interesting to receive analogous data on chromium polycrystals of technical purity using the same experimental technique.
Both in the case of quenching and preliminary deformation, a considerable number of deformation defects should be produced in the samples.

Titanium Grade1 powder (grain size: 75-180µm) with 30 vol.% and 10 vol.% concentrations of B4C particles (grain size: 45-75 µm) were prepared.
Fig. 2 Multilayer test pieces (5 layers) with Ti+10 vol.% B4C powder on Titanium Grade2 substrate (left), cross section of the Ti+10 vol.% B4C deposition on the Titanium Grade2 substrate (right) Table 1 shows the welding parameters (pilot arc current, welding current, powder feed, travel speed, seam length and number of deposited layers) used for the test seams.