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So squeeze casting is an effective processing technology to produce castings with full density and fine-grained-structure for Al-Cu-Mg alloys[2-6].
Typical microstructure of gravity cast specimen is presented in Fig. 1a, which is mainly composed of large equiaxed grains with an average grain size of 60-70μm, and the grain boundaries are decorated by continuous and coarse eutectic phases.
Micro-shrinkages at grain boundaries and porosities in grain are eliminated, while those are obviously observed in gravity cast specimen, as shown in Fig. 1a.
The eutectic phases at grain boundaries are generally dissolved into α-Al matrix and only a few compounds remain.
From Fig. 5b and d, a large number of dimples are found in natural aging alloy.

The grain boundaries are revealed distinctly by changing the direction of the main dendrite axes in the individual grains.
At magnification of 50x, grains with characteristic dendritic structure are observed.
The iron addition of 0.16 wt% causes grain refinement.
The results show, that due to grain size reduction, the alloy tensile strength increases.
Acknowledgements The financial support of the State Committee for Scientific Research of Poland under the grant numbers 11.11.170.318 – 11 and 11.11.180.653 is acknowledged.

The bright areas belong to matrix areas with high proportion of W (element with the higher mean atomic number).
The WC grains are located inside the "splats", where the temperature achieved is not high enough to produce the dissolution of the grains.
W2C has been indentified around the WC grains.
It has also been observed that in the nanometric coatings the WC grains present smaller grains.
Due to the plasma created with He is less energetic, WC decomposition is lower and therefore it is possible to retain a high number of WC grains in the microstructure of the coating.

The present study presents a quantitative study of the precipitation kinetics (size, volume fraction and number density) in a wide temperature range (450-800°C), realised by coupling systematically Small Angle Neutron Scattering (SANS), Transmission Electron microscopy (TEM) and Tomographic Atom Probe (TAP).
A great number of studies later in the 1970’s [2, 3] showed that the phase responsible for hardening was Fe2SiTi, which is a spherical, coherent and cubic phase.
It was then cold rolled up to 75% thickness reduction in the aim to have smaller ferritic grains.
The matrix remains fully ferritic all along the heat treatment, including the 900°C solution treatment, with a grain size of about 25µm.

Nowadays there are a number of measuring devices and procedures to determine both the value of the amount of dust.
This subject is studied by many experts worldwide, so there are already a number of measurement methods.
This is also stored and can therefore be taken any number of flat and curved surfaces of pipes, air-handling unit and end elements.
We distinguish four types of particles - grains of sand or plaster, sawdust, wood chips and fiber insulation.
Furthermore, it is possible to identify larger organic particles, e.g. pollen grains.

The permanent reflector blocks are fabricated from grade PGX graphite, a medium-to-fine grained, molded structural graphite.
These blocks are fabricated from grade PGX graphite, a medium-to-fine grained, molded structural graphite.
Also, inspection methods, criteria, and number of inspection in the material are defined in the inspection standard.
Also, inspection methods, criteria and number of inspection for visual inspection and non-destructive inspection are described.
(1) where X is the average strength, s is the standard deviation, n is the number of specimen, k1 = 2.326 and k2 = 1.645 are constants.

Physisorbed PTCDA molecules exhibited a stacked-grain structure covering completely ITO surface.
Metal oxide surfaces are beyond any doubt very complex systems owing to the fact that a number of challenges are present in comparison to metal surfaces.
A stacked grain-like structure of PTCDA molecules is commonly observed in this attempt.
The grain-shape structure of PTCDA molecule is originated from the interaction of the π- π electron stacking of PTCDA molecule and the dangling bonds of ITO substrate.
Further, the metallic tip is located on top of the single grain-like feature of PTCDA molecule and temporally the feedback loop was disabled (keeping the tip-sample separation constant during the voltage sweep).

It was noted that a large number of large-sized black precipitates were formed in the steel during the creep tests, especially during creep test at 180 MPa.
They suggested that in tempered martensitic 9Cr-4W steel W was enriched in δ-ferrite grains more than in the martensite.
Precipitate P21 being identified as M6C (Fe3W3C) carbide seems to be present within a δ-ferrite grain.
Black precipitates within δ-ferrite grains, as shown in Figs.5(e) and (f), can be also considered as the M6C carbides precipitating during the creep tests in the steel.
The precipitation of a large number of the M6C precipitates would consume solute W and Cr atoms in δ-ferrite matrix, resulting in a decrease in the stability of δ-ferrite and finally leading to a reverse-transformation of δ-ferrite back to austenite.

The carbonation characteristics of Ca-based CO2 absorbent hydrated by water were investigated as part of a multi-cycle performance study, and the change of the microstructure, pore radius and specific surface area of the absorbent with the number of cycles was researched.
Sorbent (CaO) derived from natural limestone markedly decreases in its reactivity over a number of cycles of reaction with CO2[9-12].
Much current and promising research involves the investigation of a number of different methods to either reduce the rate of decay in reactivity, to boost the long-term reactivity of the sorbent or to reactivate the sorbent[14,15].
May also see from the chart, Because parts of CaO crystal grain has not been activated, and has little big pore, which lead to the activity of the absorbent not obtain completely restoration。
The following results were obtained: (1) The conversion of Ca-based absorbent is enhanced because the treatment by hydration process with water enhanced the specific surface area and improved the particle size distribution; (2) The activity of the spent absorbent which cycled many number can be reactivated effectively by hydration process with water, and such process operates easily and is inexpensive

Especially the grain size, the dendrite arm spacing and the preferred growth direction may differ slightly even within one cast cluster.
A number of 2 - 5 neurons in the hidden layer turned out to be suitable.
The crack propagation in course grain alloys exhibits sometimes a discontinuous progress and may cause additional scatter [6].
The grain size, differing from specimen to specimen, is of superimposed influence. 5.
TH Darmstadt, 1983 [6] Müller, F., Scholz, A., Berger, C.: Creep Crack Behaviour of a Course Grain Nickel-base Super-Alloy.