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The figure (Fig. 4(b)) shows that the surface ceramic coating has a lamellar structure which has been formed by accumulating large numbers of flattened splats.
In laser remelting process, the surface ceramic coating is heating, melting and recrystallized, and forms fine grains (Fig. 5(b)).
The deepness of molten region and grain size are correlative to the process conditions, such as laser power, size of laser spot, scan velocity and materials’ thermal-physical properties.

Application of unconventional processing methods results in grain size reduction and increase of yield stress.
Chemical compositions of alloys with differentiated chemical composition for plastic forming were elaborated and they contained mainly Al, Mn, Zn, Zr, and rare-earth elements that create thermodynamically stable phases on grain boundaries.
These numbers show the extent to which lithium additive caused deterioration of electrochemical corroion resistance of magnesium alloy AZ31.

The HA peaks are better resolved after calcination as a result of the growth of the grains.
The HA peaks are sharper than for the sample calcined at 500 ºC, indicating that the temperature of the substrate during deposition was high enough to cause grain growth in the coating, but no phases associated with the decomposition of HA are detected.
A small number of dense particles can be seen in the coatings, as well as hollow spheres with a dense skin, distributed in a matrix of unmelted, porous aggregates.

The crack growth behavior is affected by metallurgical factors, such as grain size, material microstructure, inclusion etc[12].
It is also worth to consider that the grain size of the material is 0.1 mm and the transition crack length is 0.065mm.
In axial loading case, crack length is steadily increased with the number of cycle under axial loading case.

There is the hypothesis that the cyclic loading and moisture conditions cause deterioration in accumulated force can cause a complete fracture of the prosthetic crown after a critical number of cycles. [1], a fact that was not observed in this study with the parameters used for cycling Mechanics, based on previous studies [16,17] in which the applied force in mechanical cycling was similar to 80 N at a frequency of 4.0 Hz and 1.000.000 cycles.
The degradation propagates from the surface into the zirconia through the contour of the grain.
Under stress occurs the transformation of the tetragonal phase to monoclinic of a grain, increasing its volume by 4.5% leading to expansion of this tensioned region, which should compress the crack and prevent its spread, but with moisture penetration, crack propagates to deep layers, resulting in an increase in surface roughness and compromising the mechanical properties of the material [5,8,20].

At higher magnification boundaries of the primary austenite grains, the individual needles of tempered martensite and M23C6 chromium rich carbide particles were observed (Fig. 2).
The previous austenite grain boundaries and individual needles of tempered martensite are also visible.
These particles were found in the images of the replica after electrochemical dissolution in a minimal number.

The materials used for brazing were fine grain graphite R 6710 plates from the German company SGL Group and the CFC NB31.
The number of samples investigated per system listed in Table 1 (TiC, TiC0.2, Ti and uncoated graphite) was four.
The bar in Figure 6b labels the shear strength range of the used fine grain graphite.

In Spite of that, We still have to think carefully about the factors as the big difference of absorbing gas ability between liquid and solid state of gold alloy; big difference of specific density and melting point between gold and alloying elements; big alloy thermal conductivity; high volume and linear contraction in the process of preparation gold alloy target billet, which will lead to many problems like severely macro-segregation and micro-segregation, coarse dendrite microstructure, big unhomogeneous of grain size and distribution, inclusion, serious central shrinkage cavity and porosity, serious surface defect, high reject rate that made by casting crack and so on.
With more than ten years，effort, China have got great achievement in the target making field of precious metal, these Chinese companies are able to product a series of target production like pure gold,1N14, 2N18, rose gold, rhotanium; in addition, they have applied for tens of patents and published a great number of papers.
producing high value-added gold alloy targets are very strict and can be concluded as follows: 1) Develop new advanced gold alloy production: To meet the market requirement in production of gold alloy coating film materials, the combination effects of major adding metals and micro alloying elements should be investigated carefully to improve the gold alloy’s chromaticity, wear resistance, corrosion resistance, high performance of optics and thermodynamics; In addition, the dosage of Au should be as less as possible. 2) Low impurity concentration: Strictly control the concentrations of C, H, O, N and the quantities of their compounds in gold alloys, special attention should also be paid to control the concentration of some harmful compositions as Ni, Cd, and As. 3) Control the microstructure of target: Gold alloys target should have the characters of high surface quality, low porosity and central shrinkage cavity, higher density, high solid solubility and low segregation, uniform fine grain

When substitutional elements are partitioned there is little doubt concerning their effects: the rates of transformation are essentially controlled by the slow diffusion of these elements, either in the parent austenite [1,2] or in a contacting austenite grain boundary [3] or both, and are typically insignificant on the time scale of modern heat treatments.
This method, which was used in the past by a number of investigators [14-16], consists of reheating the specimen into the austenite one phase region in an atmosphere of wet-H2.
The growing ferrite grains traverse many crystals of the parent austenite, thus eliminating any strong interfacial structural effects.

This is a pink coloured granite having medium size grains, compact and showing an irregular fracture.
The other granite variety used in this work is known as Blanco Alba; a fine grain, white-greyish coloured granite.
All the mica has been converted into an amorph phase as well as the 85% of the Na feldspar, the 60% of the K feldspar, and the 57% of the quartz (these numbers correspond to the Rosa Porriño variety).