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The laser welding process resulted in the formation of equiaxed grains in the center of the fusion zone (FZ) and columnar grains near the FZ boundary, meanwhile some eutectic β-Mg17Al12 particles were observed in the microstructure.
Despite a large number of studies have been performed, several laser welding characteristic including pores and precipitation formation of Mg alloys still remain unclear.
In Fig. 2, it is also worth note that columnar grains are almost perpendicular to the fusion boundary in AZ31B joint.
The columnar grains whose close-packed direction line up favorably with the direction of maximum temperature gradient, tend to grow faster and restrict other columnar grains growth [16].
It is noted that columnar grains were almost perpendicular to the fusion boundary in AZ31B joint.

A number of examples on innovation for processing alternative resources developed in the author’s laboratory are also discussed.
There are a number of social and socioeconomic considerations that may affect the success of processing of alternative resources.
Recent Initiative and Activities There have been a number of ongoing initiatives around the world trying to address the issues.
There have been a number of cursory studies on sulfidation of weathered ilmenite concentrate under Becher process [5] and a selective sulfidation of the chrome spinels with a sulfide layer forming on the surfaces of the spinel grains have been observed.
A formation of sulfide rim is observed on the surface of chrome spinel grains, while the no sulfidation is observed on ilmenite grains.

A large number of α-Cr were re-precipitated at 800°C as shown in Fig. 4 after completely dissolved into the matrix at 950°C.
Cracks are formed both within the grain matrix and at grain boundary in alloy 6.
Large amounts of dislocations can be found on both sides of grain boundary.
Although inner dislocations cannot extend into adjacent grains, the stress they produce can force the slip system in neighboring grains to operate.
Dislocation a-Cr Grain Boundary (a) Grain Boundary Dislocation (b) Fig. 9 Longitudinal section of tensile fracture in NiCr alloys (a) Without P addition (b) 0.039P.

Channel Radiation Separation Detector PHA Angle (deg) Time (S) Speed (deg/min) Step TG KV mA Slit Crystal S Rh 40 95 std Ge FPC 25-75 108-114 45 8 0.1 P Rh 40 95 std Ge FPC 25-75 138-144 45 8 0.1 Si Rh 40 95 std PET FPC 25-75 106-112 45 8 0.1 Ti-U Rh 40 95 std LiF SC 25-75 10-90 240 8 0.1 Fig.1 The spectrum of x-ray fluorescence Table 2 Chemical composition (mass fraction, %) of TP304 steel C Si Mn S P Cr Ni Fe 0.04 0.51 0.95 0.03 0.03 18.85 8.21 Other Table 3 Welding solder and parameters Number Weldig Methd Welding current I / A Welding Voltage U / V Welding speed v /(cm.s-1) WeldingMaterial Material welding diameter (mm) gas flow (L/min) 1 TIG 90 14 10 18Ni9 Φ2.5 9 MAG 120 21 5 ER50-6 Φ1.2 15 2 TIG 90 14 10 18Ni9 Φ2.5 9 TIG 110 15 11 18Ni9 Φ2.5 9 3 TIG 90 14 10 18Ni9 Φ2.5 9 SMAW 120 28 18 J422 Φ3.2 Results and Discussion Alloy composition analysis.
The cooling rate and the parent material grain direction greatly influences the crystallization morphology, orientation.
Fast cooling rate, promote columnar grains formation, medium cooling rate to promote branch grains generated.
For Austenitic, composition homogenization reduced its stability, as a result of austenite grain size continue to grow, leading to coarse grain.
The weld metal are different and distribute unequally under TIG-MAG,TIG-TIG and TIG-SMAW welding methods, microstructure morphology and grain size of the solder layer are quite different.

In these trials the subsurface micro structural deformation caused by machining consists of deformed grain boundaries in the direction of cutting and elongation of grains.
Measurements were conducted number of times at various positions on the bar.
Figure 8 shows the deformed grain boundary.
The deformed grain was not uniform beneath the machined surface.
The hardness of 4B sample number (cutting condition: v = 180 m/min, f = 0.05 mm/rev, d = 0.1 mm and honed edge) is relatively equal to the 7B sample number (cutting condition: v = 180 m/min, f = 0.25 mm/rev, d = 0.5 mm dan chamfered edge).

The remaining questions concern the mechanism whereby H2O(g) alters the grain size and the way in which grain boundary diffusion occurs.
One possibility is that the presence of H2O adsorbed at the oxide grain boundaries hinders their movement and thus grain growth.
This would explain the extremely fine oxide grains formed in ArH2-H2O.
Furthermore, in both cases, grain size increases in the growth direction, i.e.
Evidently nitrogen can enter and penetrate dry Cr2O3 grain boundaries, but GasGascannot do so when large numbers of water molecules are present.

The histochemistry observation showed that there were many carbonic anhydrase positive grains in the cytochylema of macroghage after β-TCP ceramics powder being implanted.
On third day, a large number of β-TCP ceramics particles could be seen in the cytoplasm of macrophage.
The histochemistry investigation showed that there were a large number of carbonic anhydrase positive reaction particles in the endochylema of macrophage, which surrounded or infiltrated in β-TCP ceramics after 7 or 42 days for implantation.
As showed above, when macrophage came close to small material grains, they stretched out tiny processes to wrap the grains and phagocytized them into their body.
When getting in touch with a large material grain, macrophage stretched out tiny processes and covered the surface, then formed a cell-material sealing zone.

Size of former austenite grain was determined by GOST 5639-56 with ×100 magnification.
Size of former austenite grain conforms №6.
Sapmle number The contamination of nonmetallic inclusions, rating Size of austenite grain, rating Size of martensite needles, mcm Non-deformable silicates (fragile) Oxide spots 1 1b, 2b, 3a 1a 6, 5 2-5 2 1b, 2b, 3a 1a, 2a 6 2-4 3 1b, 2b, 3a 1a 6 2-5 4 1b, 2b, 3a 1a 6 2-4 5 2b, 1b, 2a 1a 4, 5 - 6 2b, 1b, 2a 1a 4, 5 - 7 1b, 2b, 2a 1a 4 - 8 2b, 3b 1a 4 - It is established, that chromium contains in the deposited layer in 1.32-1.45% amount, bars from growing austenite grain during surfacing prosses and, consequently, promotes forming fine-needled martensite structure during metal cooling, that is confirmed by better rating of hardness and wear resistance in comparison with samples which are surfaced by the wire with higher tungsten contain (table 1).
Samples №4-8 has hypopearlitic structure with former austenite grain size №4, №5.
What is more, there is big amount of retained austenite in the structure, that is located on boundaries of pearlite grain colonies.

Intra-granular misorientations arise due to the dislocation pile up within each grain in the microstructure.
Fig. 2 plots the distance from the grain boundary versus kernel average misorientation (KAM) and stress gradient.
Schmid factor mismatches were calculated between neighboring grains from VPFFT data.
Additionally, only points adjacent to the grain boundaries were included in the KAM calculation.
Acknowledgement This work was supported by DOE Award number DE-FG02-09ER46645.

The ultimate tensile strength (UTS) of nanocrystalline materials is a 2~5 times higher than that of coarse grain for Ni using electrodeposition, and a plastic elongation decreased from 40 to 4~1%, this is very interesting for materials science.
Fig. 9 is the microstructure photos of casting alloy No.1 and the alloy without Fe and Co[[] Wang Qiangsong,Wang Zidong,Zhu Junjun,etc al..Effects of Iron and Cobalt on Structure and Performance of ZCuSn3Zn8Pb6Ni1 Alloy.FOUNDRY, 57(12)(2008),p.1251-1256 ].It can be seen that ZCuSn3Zn8Pb6Ni1 alloy without additions of iron and cobat unfolds dendrite structure whose distance between the primary dendrite arm and secondary dendrite arm is 3mm more,while ZCuSn3Zn8Pb6Ni1FeCo alloy show typical equiaxed grain whose average diameter of grain is 20~60μm.The effects of grain refinement are prominent.
It is seen that the growth rate is very large for the smaller the radius of the particles.With such a large growth rate, it is very difficult to obtain the number of the dispersed iron nanoparticles in copper matrix melt during solidification.
Conclusion (1) In-situ iron nanoparticles can be formed during copper alloy solidification because of high undercooling,which would act as heterogeneous nuclei to achieve outstanding contribution for grain refinement
(3) Solution and water quenching treatment make the nanoparticles number increase and some preproduced precipitates grow because of exsolution and diffusion.