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Laser shock peening is a relatively new surface treatment technique that has been shown to be effective in improving the fatigue properties of a number of metallic materials [5,6].
The grain structure in this region was elongated, with some considerable distortions that may be attributed to mechanical action from the welding tool.
The HAZ was unaffected by mechanical effects from the tool, and had a grain structure similar to the parent material grain structure.
The fatigue behavior was determined by measuring the fatigue crack length versus the number of cycles for several conditions.

There are a number of film growth technologies to prepare CuIn(S,Se)2 thin film, such as spray pyrolysis[5], solution growth technique[6], etc.
The upper layer was the CIS while the bottom layer included carbon except for the small grains CIS.
The EDS analysis shows the composition of the CISS thin films number sulfurization conditions S/(S+Se) 1 400℃, 10min 0.406 2 450℃, 10min 0.491 3 500℃, 10min 0.578 The EDS analysis shows the composition of the CISS thin films (Table I).
As the temperature of sulfurization become higher, it can be observed that the preparation of CISS grain growth more fully in comparison to CISS, that's because the use of sulfur source was H2S vapor, its activity was greater than solid Se source which used for selenization.
This activity not only can let S partly replace Se for CISS formation, but also can make film generate better crystalline grains because of recrystallization.

The measurements were converted into Vicker's Hardness Numbers (VHN).
Technical Profiles of the Composite Resins and Porcelain Evaluated Material Category Brand Name Filler Weight (%) Filler size (µm) Manufacturer Microfine (MF) 3M Silux (3MS) 55-65 0,04 3MEspe, USA ClearfilAP-X (CAPX) 84,5 7-8 Kuraray, Japan Fine compact-filled (FCF) Pekalite (P) 75-85 6 Kulzer, Germany Ultrafine midway- filled (UMF) 3MFiltekZ250 (3MF) 83 0.01 - 3.5 3MEspe, USA Ultrafine compact-filled (UCF) SureFil (SF) 82 0,8 Dentsply, Germany Conventional aluminous Vitadur Alpha (VA) High leucite, large grain porcelain Vita Zahnfabrik, Germany Results The mean VHN, SR values and wear amounts were shown in Table 2.
Increased filler levels in resin materials usually resulted in increased hardness numbers[2].
Kelly et al [16] stated that many important physical properties are directly dependent on how the ceramic is made Conventional ceramic VA is described as a large grain porcelain and is also comparatively high in leucite content.
This properties may be related to its high leucite and large grain ceramic contents.

The number of pulses was 3 and 10.
Research Results and Discussion The structure of the initial silumin specimens consists of grains of Al-based solid solution containing silicon and other alloying elements, grains of lamellar Al-Si eutectic, and precipitates of intermetallic compounds and silicon [5, 6].
In the grain volume of the substrate, a dislocation substructure is detected (Fig. 2, a, section 2).
An optimum electron beam treatment mode for the TiCuN coating – silumin substrate system was found to be that with an electron beam energy density of 10 J/cm2 and number of pulses of 10.

The rollers were manufactured from ShKh15 (1 C-1.5 Cr-0.3 Mn-0.2 Si) bearing steel with the profile radius of working part – 5 mm, diameter – 40 mm The treatment regime of rolling was: the specimens rotated with velocity of 3.3 rev/s, the longitudinal feed of the roller  0.11 mm/rev, the number of passes – 3.
The phase composition and average grain size of the surface layers of specimens after MPT+R were studied on the diffractometer DRON-3.
The fatigue life curves were constructed in coordinates: stress – the number of cycles before the damage.
At that time carbon localizes on the grain boundaries and intensifies theirs interatomic interaction [15].
a b Fig. 1 Microstructure (a) of 60Kh2M steel and microhardness (b) of 50KhN (1) and 60Kh2M (2) roll steels after MPT+R The grain size on surface was 25-30 nm what confirmed NCS of surfaced layer.

Then the images captured were processed by professional software - TEMA Lite package (unfortunately with limited to ten number of particles tracked in time).
This is a result both of the normal carrier gas velocity profile and of the dynamic phenomena occurring between grains transported in quite big concentration, too.
The bounced back grains slow down and their track chaotically changes what causes the particles jet cone expansion.As was observed on recorded short movies, some particles accelerate much whilst others significantly slow down (the acceleration characteristics were analyzed during the experiments, too).
Fig. 2 The snapshot of air-polypropylene jet for p1 = 0.1 MPa and p4, = 0.02MPa and particles velocity graph; the numbers 1-8 indicate the powder particles chosen for image analysis.
This is particularly visible for the so-called slip coefficient which shows the dependence between carrier gas and transported particles velocities.This difference indicates that carrier gas accelerates the material grains to a much lesser extent that was previously thought.

It is especially important to achieve a high mechanical strength and since this is favored by a fine-grained microstructure, the aim is to produce a glass ceramic containing crystals of small dimensions which are closely interlocked.
The production of large numbers of small crystals rather than a smaller number of relatively coarse crystal poses the requirement for efficient nucleation stage of the heat treatment.
Fig. 1 indicate that there is an optimum duration of 5 hours heat treatment process at 550 °C with 10 % of weight of silver in order to produce a green glass ceramic having the finest-grained microstructure and highest mechanical properties of hardness which is about 213.6 Hv.
It is strongly dependent upon the optimum %wt. of silver act as nucleated agent with suitable heat treatment temperature to control the crystal growth with finest-grained microstructure.

Wave number：σ/cm-1 1：Oleic acid+ Si3N4 2：Si3N4 3：Oleic acid Wave number：σ/cm-1 Fig.1 Surface roughness as a function wheel speed Fig.2 Organic infrared spectroscopy testing for various feed rates (depth of cut 40mm) [4] results of Si3N4 ceramics surface[6] New processing methods High-speed and ultra-high speed grinding process is considered to one of being able to obtain high removal rate as well as effective economic methods.
Single grain can reduce the maximum undeformed chip thickness when the wheel speed is increase, so that the grinding force and the surface roughness get decreased, that is to provide conditions that improve the material removal rate and surface quality of materials.
As for the requirements of efficient processing which on ultra-smooth surface without damage, such as silicon nitride ceramics for hard and brittle machining, a Semi-bonded machining technology of abrasive are proposed [17]( Fig. 4 - 5).Abrasive grain is in a state of Semi-bonded , having a "trap" effect between hard abrasive surface and the large particles, namely when the hard and large particles penetrated make the abrasive into the surface, initiative to prevent or reduce the large particles damaging the processing surface.
The current ultra-precision machining of silicon nitride ceramic method, no longer confined to the diamond grinding wheel, but rather extended to study a variety of grain grinding wheel.

In the present work, gold nanoparticle (Au NPs) was synthesis by pulsed laser ablation (PLA) by using Q-switched, (Nd: YAG) (E=80mJ) (λ=532,1064nm) and Number of pulses (500)pulse of the gold metal target in deionized water.
Formation of the pure Gold nanoparticles is confirmed using AFM image analysis whose showed that generated Au nanoparticles were a spherical shape whit average size in nanoscale, It also showed results in atomic force microscope results show that the grain size increase by decreasing wavelength.
Laser ablation is done at (E= 80mJ, λ= 532nm, 1064nm), The number of laser shots applied at (500) pulses. to the metal target surface morphologies of the films were analyzed using an atomic force microscope (AFM), the nanoparticle solution absorbance spectra measured by (Uv-Vis) type (SP8001), The experimental setup of the PLAL process was shown as in Fig.1 Fig. 1 Show Experimental setup for nanoparticles synthesis by PLAL Results and Discussion AFM Morphology Figure 2,3 displays images of the atomic force microscope in 2D,3D and the cumulative statistical distribution of Au NPs produced in DDDW by PLAL method using Nd-YAG laser respectively.

Srivatsan et al. [9] has reported that the formation of TiB2 effectively inhibited the B4C grain growth.
The ZrB2 addition and smaller grain size were considered the major influencing factors on the increase of the flexural strength.
The fracture toughness was improved significantly due to the B4C grain refinement and more ductile aluminum existing.
The TEM images showed a number of striations, which were confirmed to be twins with twin planeas shown in Fig. 4.
Besides that, the improvement of fracture toughness was well related to the B4C grain refinement, the difference in thermal expansion between the B4C matrix and the ZrB2 particle, and the existence of the twins in B4C matrix.