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Metallographic microscopic observation and XRD indicate that the anodic oxidation begins along the grain boundary of the austenite, and then the micro-nano holes grow on the austenite and fill the entire austenite phase.
The two-step anodizing method has some problems such as a large number of preparation processes and chemical corrosion liquid contamination or high processing cost.
(e) The fifth stage that the porous channel forms and numbers of oxygen bubbles are floating up Perchlorate ions are reduced at the cathode to release chlorine. 304 stainless steel is oxidized to Fe2O3 at the anode and generates oxygen.
The surface of the sample after anodizing for 3 min can be seen that the corrosion begins along the grain boundary of austenite, resulting in a pale yellow austenite phase and black micro-nano pores on the austenite phase.
At this time, the grain boundary is not seen by the corrosion of 3wt% nitric acid alcohol solution, and all of them show uniformly distributed micro-nano holes.

The specific microstructure, with absence of texture and fine distribution of nearly equiaxed grains, point out that despite the markedly anisotropic nature of cubic zirconia, coatings can be considered as macroscopically isotropic.
Results and Discussion LPPS coating microstructure is similar to that of many bulk ceramics, with nearly equiaxed grains and a rather high density as compared to traditional Air plasma Spray (APS) coatings, whose lamellar grain microstructure usually leads to high porosity values.
If we also consider that the coatings are not textured and grains are sufficiently small (as compared to coating thickness) [5], we can thus treat them as macroscopically isotropic.
Journal Title and Volume Number (to be inserted by the publisher) 3 Figure 1.
However, LPPS coating Journal Title and Volume Number (to be inserted by the publisher) 5 0.0 0.2 0.4 0.6 0.8 1.0 1.152 1.153 1.154 1.155 1.156 (a) d420 [Å] sin 2 � � = 1.0 Å � = 1.5 Å � = 2.0 Å 0.0 0.2 0.4 0.6 0.8 1.0 1.182 1.183 1.184 1.185 1.186 1.187 (b) d331 [Å] sin 2� � = 1.0 Å � = 1.5 Å 0.0 0.2 0.4 0.6 0.8 1.0 1.152 1.153 1.154 1.155 1.156 (c) d420 [Å] sin 2� � = 1.0 Å � = 1.5 Å � = 2.0 Å 0.0 0.2 0.4 0.6 0.8 1.0 1.182 1.183 1.184 1.185 1.186 1.187 (d) d331 [Å] sin 2� � = 1.0 Å � = 1.5 Å 0.0 0.2 0.4 0.6 0.8 1.0 1.152 1.153 1.154 1.155 1.156 (e) d420 [Å] sin 2� � = 1.0 Å � = 1.5 Å � = 2.0 Å 0.0 0.2 0.4 0.6 0.8 1.0 1.182 1.183 1.184 1.185 1.186 1.187 (f) d331 [Å] sin 2 � � = 1.0 Å � = 1.5 Å Figure 4.

For supersonic dissolution of porous ceramics in the acidic electrolyzed water, DE was 30% and extension of grain boundary or micro-crack was observed.
On the ceramics, different shape-small grains are observed by ehing of grain boundary.
In both cases, extension of grain boundary and micro-crack are recognized, suggeting excellent body fluid permeation and bio- absorption in a living body.
When functionally graded HAp (fg-HAp), PDP-HAp and DDM were implanted into the subcutaneous tissues of back region in rats for 2-8 weeks, from histological evaluation, there was a significant difference in the cell number among them.
The numbers of giant cells in fg-HAp and PDP-HAp ceramics were more numerous than those in DDM granules.

Introduction Increased number of investigations and developments have been seen in the past decade in the field of magnetic nanoparticles.
The powder of NiSn-substituted Ba-hexaferrite with typical plate-like grains is shown in Fig. 1a.
In some cases the number of these inter-particle contacts is very large, thus leading straight to the formation of the target phase.
Thus, by prolonging the time of synthesis, a definite grain growth can be achieved, Fig. 2.
All this increases the "volume" of nonmagnetic regions on the grain surfaces [27,28].

In the preparation of this material, chemical structure or molecular weight of the added polymer is expected to affect ionic interaction between polymer and iron salts, and consequently the grain size and morphology of the prepared magnetite core.
In the preparation of this material, chemical structure or molecular weight of the added polymer is expected to affect ionic interaction between polymer and iron salts, and consequently the grain size and morphology of the prepared magnetite core.
It is assumed that number of nucleation site is increased by ionic interaction between the sulfo groups in PSSS and the iron ions.

In micro structural studies, precipitations in grain boundaries were noticed which are probably because of Boron combinations [Fig.7].
Moreover, in Fig.7 a decrease in the size of proportional grain was observed in comparison with common non- Boron 2024 Aluminum alloys.
Conclusion 1- The Boron effect on 2024 Aluminum alloy which has gone under controlled quench, is to reduce the aging time to 40 min with hardness peak. 2- The equal heat treatment on Boron and non-Boron contained samples, illustrates %10 hardness increase. 3- The elongation with maximum hardness equals %26 which is one the conclusions of the current study. 4- The Aging process observations promises proportional heat stability, moreover, the resulted microstructure is stemmed from the effect of Boron on grain refining.
[9] Y ucel Birol, "Production of Al- Ti- B grain rifining master alloys from B2O3 and K2TiF6", Journal of alloys and Compounds 443(2007) 94-98
[12] S.H.Razavi, " Method for age hardening of super slloy", Patent number: 20030056864, Canada,March 2003

Fig. 1a exhibits microstructure with well-defined grains, intermetallic and lesser amount of porosity can be seen for Al7075alloy.
Increasing the vol. % of Al2O3 in the composite, increases hardness gradually which is related to high hardness of Al2O3 reinforcement and grain refinement [4].
This micrograph shows that the number of pits is more and pits size large with the increasing Al2O3 content.
Higher volume fractions of Al2O3 (beyond 10 vol. %) caused segregation of reinforcement alumina oxide particles at grain boundaries which restricts the interparticle contacts further inhibiting densification.
The hardness of composites increased with increasing vol. % Al2O3 due to refinement of grain size.

Experimental procedure The employed raw materials were high purity Al2O3 powder having small grain size of about 500 nm.
The attraction mechanism of the crack tip to the particles thus ensures that the crack path is formed through a number of ductile particles.
Toughening mechanisms of ductile particle could be divided as crack bridging, grain deformation, grain pull out, crack deflection and crack termination in the particle, and the effect of crack bridging toughening mechanism is more significant than others.
When the crack meets the brittle particles, transgranular damage may happens, such as No. 1 particle in Fig. 2; in the first particle; crack extending along the grain boundary may also happens (crack deflection), such as No. 2 particle in Fig. 2; No. 3 and No. 4 particles are crack bridging.

However, during the grinding process, the grinding state always changes due to the attrition of abrasive grains and the adhesion of chips to the grinding wheel surface.
In Figure 5 (b), the Grazing wheel, as the number of the passes increases, the maximum temperature gradually rises.
A remarkable increase in temperature resulted from the attrition of abrasive grains.
It is thought that the sharpness of the abrasive grains remained higher in this case because an excessive self-regenerating function occurred without attrition of abrasive grains.

Herein, its accelerated controlled distribution and following hardening on the grains of the process material are achieved.
As a GM, there can be used abrasive grit of fused alumina № 16-80; pure fire-clay with grain size 0.25...1 mm; siliceous sand of grade 1К1О202, 2К1О202, 1К1О203, 2К1О203 and others.
Drawed with jetting the spray of CA, the grains of the upper layer of the fluidized bed as heavier ones migrate to the lower layers, and the lighter unclad GM particles, which are affected by the next portion of the spray, move to their place.
In the result of the interaction, the products with pH less than 2, that form the clad layer of the grained stucco and have coagulating power to the sol-silicate solution, cause the accelerated and at the same time forming the enormous number of gel-processing centres.