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Oxidation of alloys involves a large number of phenomena, including the formation of external scales and internal oxidation.
ST10 shows a fine grain size that is 56.72 μm, meanwhile the ST12 shows a coarser grain size that is 100.88 μm.
This is due to the large grain size with relatively few grain boundaries did not form protective oxide layer but more porous structure.
If the outward metal diffusion is faster along the grain boundary than through the lattice, the grain boundary area begins to open up next to the void.
The internal oxide will go deeper to the grain boundary area for the coarse grain due to the faraway location of adjacent grain to stop the penetration path.

This paper introduces the performance metric of DSP parallel processing system and presents a model of coarse-grained speedup of DSP parallel processing structure.
A model of coarse-grained speedup of DSP parallel processing architecture is proposed.
means the average number of instructions supported by each communication.
means the average number of instructions supported by each of the communication channels.
means the average number of instructions supported by each synchronization.

The results showed that there were a large number of micro-cracks in the fracture surface.
The fracture location was in the fine grained area near the weld.
Fig. 5 Crack morphology in fine grained region.
Sample HV0.5 Base metal near the weld zone Fine grained zone Fine grained zone near the fracture Q345R Welded joint 190, 189, 195 162, 156, 155, 161, 163 165, 166, 150, 156, 158 SEM Observation and EDS Analysis.
In the study of the fracture morphology a large number of layered distribution of the crack appeared in conformity with the banded structure distribution.

Meanwhile, the addition of Y element to the Mg-1Mn-0.6Ce alloy could reduce the grain in evidence.
The Y element combines with Mg to form compound and concentrates along the grain boundaries to prevent the grain growth.
It exhibits that great number of gray sheet phase, white polygonal phase and some small acicular phase are formed in the (D) alloy.
It is noted that the yield strength is improved with grain size reduction.
Fig. 1 shows the refined grain structures of the studied alloys.

This new and emerging methodology starts from the predicted behaviors given by their atomic counter-parts, and resolves the effects of grain boundaries, and de-convolves the grain-grain mesoscopic interactions.
Every grain possesses a highly non-linear, multiphysical, time-dependent, anisotropic response, while it is spatially interlocked to the surrounding grains.
However, because each atom must be tracked individually, the number of units required to perform a valid calculation, even for nanometer-sized volumes, becomes prohibitively large (see Table 1).
Note that greatest variations occur at grain corners, boundaries, and in (111) oriented grains.
Part II: grain boundaries and defect pinning.

Grain-oriented alloys with lower thickness are used in high efficiency devices’ production.
Materials and Methods There were analyzed two types of electrical steels: M400-65A non-oriented alloy and MOH grain-oriented material.
a. grain-oriented MOH at Jp = 500 mT b. grain-oriented MOH at Jp = 1000 mT c. non-oriented M400-65A at Jp = 500 mT d. non-oriented M400-65A at Jp = 1000 mT Fig. 1 Total energy losses as a function of frequency in the case of both types of electrical steels, measured at two peak magnetic polarizations.
This process, being adequate to grain-oriented alloys, can determine some improvement of the energy efficiency of electrical transformers.
The work of Horia GAVRILA and Doina Elena GAVRILA was supported by a grant of the Romanian National Authority for Scientific Research and Innovation, CNCS/CCCDI – UEFISCDI, Project Number 10PTE/2016, within PNCDI III “Brushless servo-motors series utilizing soft magnetic composite materials”.

This resulted in a small number of coarse extremely long whiskers shown in figure 4a.
This supports the idea of 'flow lines'5 at sliding grain boundaries although the width of these bands (around 20 µm) is significantly larger than the grain size.
The only peak present is at a wave number of 14300cm-1, corresponding to magnesia.
If the core and mantle theory of Superplasticity is believed, the majority of the deformation occurs at the grain boundaries with extremely limited deformation in the bulk grains.
These undeformed regions are generally significantly larger than the grain size, which supports whiskers only being formed at sliding grain boundaries.

The optical and electrical properties of the films were affected by the number of printed layers.
It was observed that the ink contains FTO grains with the sizes in the range 20 to 30 nm.
It was observed that the films comprised of small grain size particle at the range of 20 to 30 nm with the less crack on the surface.
The L4 thin film may has compact small size grains, less void and uniform thickness.
The optical and electrical properties of the films were affected by the number of printed layers.

The austenite grain size was determined by the liner intercept method.
Fine dispersed carbide and nitride can pin austenite grain boundaries, thus growth of austenite grain is inhibited.
So niobium can refine austenite grain of heavy rail steel.
(a) Hot-rolling (b) Quenching (c) Annealing (d) Normalizing Fig. 1 Representative metallographs of heavy rail steel Fig.2 Relationship between the austenite grain size and niobium content The results show that, in the present study, the rolling, annealing and normalizing microstructure of heavy rail steel are all pearlite, however, a small number of samples contain a few proeutectoid ferrite, as shown in figure 1.
But when the niobium content is excessive, a large number of precipitates containing niobium appeared in the austenite grain boundaries, thus the properties of austenite grain boundaries are changed.

The thermo-mechanical processes associated with this kind of severe plasticity causes a refinement of the grains in the material often leading to a net reduction in the average grain size [6, 7] and property alterations clearly different from that in the coarse grained material [8].
Thus the dislocation density in the material is increased after SPD, likewise the effective grain boundary area increases accordingly with grain size reduction.
Due to the limited number of slip systems in Mg only 2 independent slip systems, namely the basal plane (0001) and one of the 3 close packed directions, can be activated at room temperature in the material.
The reason for this being a combination of two microstructural effects (i) the refinement of the relatively large second phases and their distribution at the grain boundaries, and within the grains of the α-Mg phase thus leading to mechanically induced precipitation hardening, (ii) as the number of passes increases, the plastic strain and thus dislocation density increases leading to dislocation hardening.
The present study has thus demonstrated that: (i) ECAP processing of AZ80 magnesium alloy results in the formation of microstructures which are dependent on the number of passes.