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Foam concrete aggregates must meet the following requirements: high dispersion and homogeneousness of grain composition.
The use of sand containing grains of large size can lead to destruction of cellular structure and deterioration of strength and thermal characteristics of foam concrete.
The data presented show that for a number of wall concretes, only by-products of the fuel and energy and metallurgical industries can be used, without spending and saving irreplaceable natural resources.
A number of wall concrete was obtained on the developed cementless ash-silica binder: ash-slag concrete, wood-cement concrete, non-autoclave foam concrete, whose properties are listed in Table 8.
New compositional binder and fine-grained concrete based on it from secondary mineral resources.

The heat treatment process and coding number of every sample see Table 2.
The grain size measured is 12 rate.
So the formed spherical austenite grains in the martensite are more and finer.
Under this experimental process, the grain size is 12 rate quenched at 830°C.
The reason for this may be relative to the refinement of austenite grain and the non-uniform of carbon density in the austenite grain

The required force for deforming a grain depends on the particular grain orientation towards the loading direction (Schmid factor).
(a) undeformed (b) 10 % (c) 20 % Fig. 2: Deformation of grains in the simulation.
A polycrystalline model geometry is created, which is based on data as the average grain diameter or as the grain orientation distribution.
This scattering behaviour in terms of the normalised standard deviation decreases when the number of grains is growing (Fig. 5b).
(b) Standard deviation over grain number.

AF/PSTM is a new number of SPM, compared with former photon scanning tunneling microscope (PSTM [7]), it uses two symmetrical laser beams to illuminate sample to eliminate the optical artifact dues to incline angle of sample surface.
That is to say, the exotic grain is not on the grating surface.
The image of grains dia met ers of diesel oil additive are bigger than that of good gasoline additive in common, although most of the grains are smaller than 500nm, there are several grains are smaller than 100nm.
The grains of ropy gasoline additive image are uneven, the biggest is several micrometers, while the smallest is smaller than 50 nm, and the micrometer grains are in the majority in mass.
Above three topography images of additives imply that the smaller the grains are, and the even the grains are, the better efficiency they will achieve.

Similar crack growth experiments were conducted on a number of specimens at various stress levels, and the experimental data were recorded.
Grain growth was observed in the fusion zone.
On the other hand, the stir zone of the friction stir welded joint shows very fine equiaxed ferrite grains with grain boundary martensite (Fig. 3e).
The fine grains are outlined by sharp grain boundaries.
Large number of crack initiation sites is visible in fracture surface of GTAW joint compared to their counterparts.

The grains boundaries is β-phase (Fig 5a).
In some grains equiaxed α-phase are found (fig. 5c) [22].
HIP was conducted for a decreasing of pores and inside defects numbers.
Grains size influence from fractional composition.
Microstructure DLD metal contains fine acicular α-phase inside β-grain.

But the mechanical test results showed that the Vickers hardness number of welding seam was greater than the standard.
Under the same scale (500X), the size of different regions of welded joint was obvious, particularly fine grained region and coarse grained region.
Fig.2-Fig.3showed the metallographs of base metal and fine grained region were normal,but there were some carbide precipitates in the grain boundary.
The crack was intergranular in coarse grained region, and ended at fine grained region of HAZ.
Too many small cracks locate in the vicinity of the main crack, and the sizes of some cracks are in about grain size, others are as large as some connected grains.

Metallographic study was conducted using optical microscope for laser modified layer thickness and grain size.
A number of different laser sources such as Nd:YAG (Neodymium:Yttrium-aluminium-garnet), CO2, fibre laser and HPDL (High Power Direct Diode) laser system have been widely studied.
Grain refinement occurred in the modified layer as shown in Fig 1 (c) where large grain size observed in the substrate region [B].
At 500x magnification, the reduced grain size in molten pool [A]was unnoticed.
Heat affected zone labelled as [C] was visible at the higher magnification with finer grains formation.

Still, we observe a few particles, which seem to be nucleated at austenite grain boundaries.
The dislocation densities directly determine the number of available nucleation sites and, therefore, the number density of the precipitates.
However, it does not reach the observed number density.
Phase Tstart [°C] Number density / m-3 Rmean [nm] Exp.
Phase Tstart [°C] Number density / m-3 Rmean [nm] Exp. obs.

Consequently, viewing the surface of the film, the number of grains is reduced as the film thickens.
Grain boundaries in diamond film have been reported using this method by Geier et al [10].
The general procedure is to choose a surface of position B for examination, for example one of the FEA protrusions, polish the surface using ion milling to determine the Kikuchi pattern for a sufficient number of positions, mapped against the SEM picture, to determine the grain boundaries.
The Kikuchi pattern allows the grain orientations and distributions to be obtained and mapped.
• EBSD provides a useful method for determining the crystal orientation and grain boundaries of films, may be used to map the film texture, and can also provide a 3D reconstruction of the grain structure of the film.