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Introduction Recently there has been an interest in developing metals with nanoscale grain structure so-called nanocrystalline metals.
Nanoscale and complex structure The method for manufacturing bulk nanocrystalline strong materials is to introduce large numbers of defects such as interfaces or dislocations, which interfere with the ordinary mechanisms of slip or twinning.
Black thin line represents misorientation angles >10º and dashed coarse line represents selected prior austenite grain boundaries.
The inverse pole figure colour map image in Fig 3 shows the bainitic structure formed at 250ºC from an austenite grain.
It is revealed that a prior austenite grain was divided by packets consisting of three blocks of which the orientations are entirely different to each other.

It is completely pure with ideal grain shape, what enables to create ideally dense structure in the polymer material.
Evaluation (number of ٭) Behavior of the material in the aggressive substances ٭٭٭٭٭٭٭ Material shows no changes ٭٭٭٭٭٭ Unsticking of the material from the microscopic slide ٭٭٭٭٭ Softening and unsticking of the material ٭٭٭٭ Color changes on the surface ٭٭٭ Unsticking + color changes ٭٭ Blistering of the material + unsticking + color changes ٭ Total material failure (cracks and loss of adhesion) Determination of Shrinkage.
The shape of the Dorsilit grains approximates the shape of the sphere, while the grains of the packaging glass exhibit sharp edges resulting from crushing the glass.
In the case of flexural strength, an important role seems to be also the distribution of different sized grains of the filler along the length of the sample and the amount and size of the filler at the point of greatest load of the samples.
The mass perfectly filled the space between the concrete wall and the anchored steel rod, and the glass grains likely get into the turns of the threaded rod, which increased the adhesion of the polymer anchor to the anchored rod.

Traditional production methods such as conventional solidification, for example, characterized by low cooling rates around 0.1-50oC / s, generally provokes inclusions, segregation and coarse grains in the solidified material, consequently requiring further thermal treatments to ensure grain refinement, which increases the production cost.
The convective heat transfer coefficient was calculated by the following equation: (26) where and , are the Reynolds and Prandtl numbers, respectively.
Then, a study of the effect of the number of nodal points and time intervals was carried out.
The cooling rate until the solidification start temperature determines the total number of active nucleus that can grow.
The higher the solidification speed larger is the number of nucleus and the greater the refinement of the microstructure.

From the nature of hot metal forming, temperature is the important and often dominant factor which affects the process kinetics and grain recrystallization dynamics within the material.
It was found that dynamic uneven recrystallization causes inhomogeneous distribution of grain boundary grooves which is reason for the formation of such defects as die streaks on anodized or painted aluminium extrusions [4,5].
The catalogue of a number of defects in aluminium extrusions is presented in work [6].
During a number of investigations, it has been proven that NIR (near infrared radiation) and SWIR (short wave infrared radiation) cameras are most suitable for temperature measurement on hot metal surfaces.
A number of defects as following: cracks, scratches, impurities, flakes can be detected using customized algorithms.

The bronze alloy also contains a large number of copper sulphide inclusions.
The characteristic twinning of grains and a large number of copper sulphide inclusions are visible in the bronze structure imaged by a light microscope PME3 (Fig. 4).
In this case, significant number of cracks occurred and the compactness is mainly provided by the cohesive layer of corrosion products on the surface.
Fig. 4 Twinning of grain and deformed copper sulphide inclusions in the axe bronze alloy (light microscope PME3) Fig. 5 Cracks in a metal core – a fragment of the bronze sickle ( X-Ray imaging) The bronze sickle was made from tin bronze with the average of tin content 10.6 wt. %.
Fig. 6 presents an image from a light microscope where is clearly visible that the sickle bronze alloy contains a large number of copper sulphide inclusions.

A Consensus Partial Least Squares Regression for Analysis of Near-infrared Spectroscopy Dan Peng, Qingchen Nie College of Grain Oil and Food Science, Henan University of Technology, Zhengzhou, China, 450001 pengdantju@gmail.com, lnqs2005@163.com Keywords: partial least square regression; consensus strategy; near-infrared spectra; prediction accuracy; optimization Abstract.
Set parameters for the calculation, including the number of the training set (H), the number of the prediction set (K), the number of sub-models (L) and the Criterion for the sub-models.
The Number of Sub-Models Fig. 2 The RMSEP changes according to the number of sub-model.
The number of sub-models is another important parameter to affect the stability and accuracy of a consensus model.
Therefore, the number 50 is used for further study.

Nugget and TMAZ exhibit small grains which result by the thermal and mechanical interaction with the tool.
The current state of the art shows a small number of studies for friction stir welding of Al / Mg dissimilar joints.
The average grain size was reduced from 28 μm to 4.7 µm.
This zone is characterized by the fine grains which results in higher strength.
Within TMAZ a strong grain refinement including an increase in micro hardness could be observed.

The applicability of heavy concrete and ceramic bricks processing wastes as well as such large-tonnage extraction of iron ore as sandstones granulation selection as mineral additive for non-autoclaved aerated concrete production as well as a number of accompanying issues of the of a high-quality pore space structures formation control are considered in the present article.
With regard to aerated concrete an attempt to replace cement with low water demand binder (LWB), in the production of which a clinker component, a number of mineral additives and a superplasticizer were crushed in a single technological cycle was made at the time.
At the same time the durable grains of quartz in rich contained in heavy concrete do not apparently have time to crush due to the presence of a large number of softer products (cement hydration products) due to which the increase in the specific surface is mainly ensured.
It was found that this plasticizer (and similar to it by the mechanism of interaction on cement systems) effectively dilutes the paste on the basis of fine-grained portland cement and even more effectively affects the paste from heavy concrete waste, significantly reducing the fluidity point.
The reason for this effect is a large number of positively charged centers on these materials surface particles which ensure efficient adsorption of plasticizer molecules [17-21].

A number of researchers have used experimental approaches for optimizing process parameters of the SLS process.
These properties include powder size distribution, packing density (the ratio of total volume of powders inside the packed bed to the total volume of the bed) and average coordination number (average number of neighbors of each particle inside the packing).
However, as the number of particles inside the system increases, the model faces significant increase in runtime.
In order to reduce the runtime for simulation of packing of large powder beds, the bed is divided into a number of grids each holding a relatively small number of particles inside them.
Moreover, σ = F(1)n πr2 = −F(2)n πr2 (26) is the normal stress applied on the particle grain boundaries.

Based mainly on field observations related to the conditions, a number of indices are used in prediction of the outburst.
To comply with the legislation, mitigate the risk of the outbursts and reduce the impact on mining advance, a number of technologies and methods have been developed since then.
The method has been successfully applied in a number of active underground coal mines in China [6].
The main roof of the seam is finely grained sandstone and about 2 m in thickness.
Key Geomechanical and Seam Gas Data A number of key seam gas data were required to assess the outburst risk of the #15 seam.