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Flexible sheet metal forming processes represent a big challenge, which have involved a number of researchers all over the world in the last decades.
Vanderhasten et al. [1] carried out tensile tests on superplastic Ti6Al4V sheet samples and revealed that the deformation behavior of this alloy can be classified into essentially four main domains: from room temperature up to about 650°C, characterized by no dynamic recrystallization nor grain boundary sliding; between 725°C and 950°C and with strain rates lower than 5x10-3s-1, corresponding to superplastic behavior; temperatures above 950°C and strain rates below 5x10-3s-1, corresponding to dynamic grain growth and disappearance of super-plasticity; above 750°C and high strain rate, classified as hot deformation mechanisms combined with dynamic recrystallization.
Fig. 1 Equipment used for the high-speed ISF The whole experimental campaign was performed taking into account a number of potential advantages deriving from the application of the high-speed ISF to the Titanium forming, such as: - the possibility to work without the need for properly designed dies; - the reduced setup time, with respect to the conventional hot drawing which requires the whole tooling heating; - the absence of an external heating source, since heat is self-produced by friction and high speed involved in the process.
Fig. 8 shows the through thickness microstructure of the sheet deformed at 500 m/min with a tool depth step of 0.1 mm (from outer radius to inner radius from left to right in the figure): it is evident that the microstructure does not change either in the morphology nor in the grain size, being still characterized by elongated grains of a phase and intergranular b phase, as it was in the as-delivered condition.
Therefore, the temperature increase due to the process was not high enough for reaching b-transus temperature or a significant grain growth.

In this paper, we introduce a policy for fine-grained access control which is able to support the specifications with sufficient policy constraints, and then we present a methodology based on semantics to detect whether there are policy conflicts and then produce the XACML policy document.
In this paper, we present a fine-grained policy and provide a methodology to verify whether it is right.
In summary, the main advantages of the policy are fine-grained, reusable, type-checked specifications of access policies.
There are three kinds of constraints when a role is defined: 1) Base number constraints; 2) Leading role constraints; 3) Mutual exclusion constraints For example, There is a policy—Entrypolicy which describes the roles in the system as the following: policy Entrypolicy { roles Other Secret: Other EnOwner: Secret } Views: View is a static construct to describe access rights, which are permissions or denials for operations on objects.

In order for a TCO to be used in photovoltaic applications, it must meet a number of requirements.
The scanned area is of 2x2µm² for all the sections of the sample and the average grain size was calculated after many random grain choice measurements with Gwyddion software.
In addition to the increase in grain size, also the grain shape was reformed; the grains transformed from spherical to pyramidal shapes as it is clearly shown in the pictures of the surfaces reported in Fig. 5.
As the distance varies, the thickness, grain size and shape appear to change.
Mainly, we noticed that as this distance increases, the roughness decreases, the grain size increases and the shape of the grains changes from spherical to pyramidal.

Fig. 2a shows fine grain structure of the as-received bars.
Mean grain size calculated from statistical data using log-normal distribution function is 38 µm.
The number of cavities significantly increased in a macroscopically necked region of the creep specimens.
Besides formation of cavities, intensive precipitation of a new phase can be seen along the grain boundaries (Fig. 2d).
Appropriate heat treatments leads to fine grains with convoluted microstructure composed of γ and α2 phases.

Lots of pores were found in the grain boundaries of all the films.
In our case, the green emission center at 510 nm (2.43 eV) is related to O vacancies, especially those O vacancies in the grain boundary and grain surface regions.
A large number of O vacancies are therefore expected to exist within these grain boundary regions.
The H atoms in the grain boundary regions are not as stable as the substitutional H atoms inside grains.
At 650 °C annealing temperature, a large fraction of the H atoms in grain boundary regions would diffuse out, forming O vacancies in grain boundary regions.

The grain sizes exhibited variation, with the largest grains measuring approximately 100 µm in diameter.
Additionally, annealing twins were observed within several grains across the material.
However, the grain size according to EBSD was much larger, and the largest grain widths were nearly 500 µm.
Grain size reduction post-SSP treatment is also visually discernible, with an observable increase in the number of grain boundaries closer to the surface.
Applying SSP treatment on the surface leads to deformation twinning and grain refinement

The post-tempered weldment exhibited improved grain refinement over the as-welded.
Compared with the as-welded sample, only the post-tempered sample showed smaller-sized grains.
The grains in the weld zone of the post annealed sample were found, on the average, to be the largest.
The presence of the Cr-rich carbide is almost negligible in the post-normalized and post-tempered samples while the post-annealed has a high number of the Cr-rich carbide at the core of the joint.
Also, annealing process resulted in grain coarsening which is unfavorable to mechanical properties [20].

The number of micro-inclusion is 36.5/ mm2 in normal billet.
The number of micro-inclusion is 58.5/ mm2 in compound casting billet which is 60.27% higher than normal billet.
After wire feeding, in liquid steel, there are more along grain boundry sulphide, and there also are aggregation Al oxide.
In tundish, the main micro-inlcusion in liquid steel is the oxide and sulphur whose particle size is 10μm, and also there is little along grain boundry sulphide.
After wire feeding, the number of micro-inclusions is 75.2/mm2 which is 31.8/mm2 more than LF refining.

Modern Technologies of Metal Processing in the Socio-Cultural Context Diaghileva T.V.1, Sokolov R.A.2,a, Novikov V.F.2, Deneko M.V.3 1The Department of Humanities and Technologies, Tyumen Industrial University, 625000, 38 Volodarsky street, Tyumen 2The Department of Physics, Methods of control and Diagnostics, Tyumen Industrial University, 625000, 38 Volodarsky street, Tyumen 3The Department of Foreign languages, Tyumen industrial University, 625000 38 Volodarsky street, Tyumen afalcon.rs@mail.ru, (corresponding author) Keywords: internal stresses, relaxation coercive field force, structure,proportionality limit, strength limit, grain size.
Nowadays there is a socialization of science due to the increasing number of scientific personnel and research institutes.
They identified the main methods for calculating the value of internal stresses and the average size of the grain structure [8-9].
The values are determined (figure 2) using the method for calculating the grains’ size (D) and microstresses.
There is a slight internal stresses relaxation and a decrease in the average grain size.

The original austenite grain structure is shown in Fig. 5 [15].
The fine austenite grain zones offer more nucleation sites.
Grain boundary character distribution.
It is known that different types of grain boundaries have different energy and mobility.
Further analysis [19] shows that the area percentages of the 'distortion-free' regions are 7.24% without and 5.42% with a 14-T field and the percentages in the number of the 'distortion-free' regions are 55.41% without and 51.64% with a 14-T field.