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Due to the high number of aluminum-magnesium alloy applications, the welding process becomes an indispensable step for the formation of complex geometries materials.
In addition to intermetallic formation, fusion welding can present joints with several problems: grain growth, formation of solidification structures, generation of voids, welding distortion, high residual stress, and others [3].
According to Gungor et al. [6], welding aluminum alloys AA 6082 by the FSW process, the increase in the heat input results in natural aging of the weld zone with fine dispersion of precipitates inside the grains, which means that the hardness does not increase.

Research has shown that, there has not a large number of chemical reactions at the interface between the SiC particles and magnesium, but in some parts of the interface with high temperature, reactions would occur as follows: 2MgO + SiC==Mg2Si + CO2 (1) 2Mg + SiO2==2MgO + Mg2Si (2) In this experiment, there has not apparent chemical reactions between the SiC particles and magnesium during the laser welding process.
For the samples, the microhardness of the welded seams was higher than the substrate attributed to the fine grains and the solution of the white magnesium intermetallic compounds, which played an important role in fine-grain strengthening and solid solution strengthening.

Introduction Ti3SiC2 combines both the merits of the metal and ceramics and has a number of exceptional properties[1-3].
It is reasonable to understand that Al can serve as the melting pool during sintering due to its low melting point, Al preferably distributed at the grain boundaries after mixing, and Ti3SiC2 can nucleate and grow up on it.
Ti3SiC2 can nucleate at the grain boundary between TiC micro-twins[13].

FAPs with grain sizes of #100, #600 and #1000 were investigated for coarse, medium and fine polishing.
Experimental conditions Polishing Machine Polyem-1205(5-axial) Spindle Speed (RPM) 800-900 Workpiece SKD-11 Feed rate (mm/min) 400 Polishing length (mm) 120 Pressure (kgf/cm2) 5 Grain Size (Mesh) 100 , 600 , 1000(hydrophilic FAP) 100 , 400 , 800 , 1800(3M Pad) Initial surface roughness Ra 1.5639µm Experimental Results Polishing characteristics of the commercial thermo curable FAP.
Loading and glazing occurred on the pad's surface; therefore, active abrasive numbers were gradually reduced.

Electrodeposition reaction can be described as heterogeneous in nature, and the overall reaction consists of a number of sequential steps as convective diffusion, electromigration and electrochemical reaction at the solution/metal interface.
This value is nearly three times higher than that in conventional Invar alloy, which results from strengthening due to fine grains [11].
This value is nearly three times higher than that in conventional Invar alloy, which results from strengthening due to fine grains.

Rough processing was performed by single face lapping using a tin lapping plate with two types of abrasive grain (GC2000 and WA4000).
Table 1 Lapping and polishing process conditions Workpiece Quartz substrate (AT-cut) 5.2 mm in diameter㧘60 µm - 100 µm in thickness Lapping plate / Polisher Tin / Non-woven fabric Rotational speed of plate / polisher N = 60 rpm Rotational speed of workpiece n = 60 rpm Lapping / polishing pressure p = 82.1 kPa㧔2.0 kPa in the case of protecting film㧕 Abrasive grains / Slurry GC2000㧘WA4000 CeO2㧔Average diameter 0.7µm㧕 Formation of Protective Electro-Plating Film Fig. 1 shows the sectional profile of the polished quartz substrate measured by a stylus surface roughness measuring instrument.
Thinner quartz substrates could not be achieved even after a large number of experiments due to the lack of uniformity in the electron wax layer and the deleterious effect of small amounts of dust contamination in the wax layer.

‘G’ forces or Number is given by the equation, (1) Where ‘R’ is the radius of the arm in m, ‘ω’ is the arm rotational speed in rad/sec and ‘g’ is the acceleration due to gravity in m/sec2.
Brinell ball makes the indentation too deep from the top surface and also it will be wide so that the test measures an average value of the hardness over a larger surface area of the material, which will help in predicting the a more accurate value considering the different grain structures and also any irregularities in the non homogeneity of the material.
Ceramics International, 1997, V23, pp 73-83 [2] Sui Yanwei et al, Evolution of microstructure in centrifugal cast Al-Cu alloy, Article ID: 1672-6421(2010)01-043-04 [3] K G Basavakumar, ‘Effect of grain refinement and modification on microstructure and impact properties of Al-12Si and Al-12Si-3Cu cast alloys’-Trans.

Introduction The idea of optimized utilization of raw materials was adopted by number of research institution all over the world, what for the recycling is contemporary the main scientific interest.
Recycled material is mechanically crushed to grit, of which are subsequently using various techniques exploited grains of metal.
Usually are applied multiple procedures for metal grain acquisition (by floating, centrifugation, blowing, etc.).

It can be seen that the size of Mg grains is about 150µm which is bigger than that of the starting materials in Fig.3 (a) and (b).
It is considered that in the SPS process, Mg particles firstly melt under the high temperature created by the spark in the particle- contacting surface, and during the cooling, the melting magnesium is crystallized and the grain growth occurs.
Acknowledgement This work is supported by the National Natural Science Foundation of China under the grant number of 10574102.

The fine grain of superplastic DSS which undergoes superplastic deformation also enhances the diffusion of carbon atoms as it provides a larger number of grain boundary diffusion paths.