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Hydration is simulated based on spherical grains.
Average grain size was 5 μm.
Nevertheless, green concrete could be produced with high dosage of fine-grained RHA without loss of strength.
The number of trees is a reflection of pore fractionation: the number of transport routes through the specimen is hereby restricted.
The effect of increasing sensitivity of the approach by taking lager numbers of tree branches is also obvious; the smaller pores detected in this way connect branches of the trees declining the number of independent trees.

It was concluded that premature failure of the refurbished blades was due to the presence of γʹ -denuded zones alongside grain boundaries promoting preferential deformation alongside grain boundaries intergranular failure.
On the fracture surfaces a number of micro-cavities which can serve as creep failure mechanism source were noted [4].
The engine was installed and operated on liquid fuel till 2005, during that period the total number of starts was 933.
Backscattered electrons (BSE) were used to obtain atomic number contrast and topographic images of the damaged and fractured areas.
Grain size and carbides precipitations In addition, also grain growth (coarsening) is shown, coupled with high level of oxidation, degradation and deterioration.

In the process of grinding, abrasive grains cut into the workpiece, to extrude and score the material, which make the material flow to both sides of abrasive grains.
The increasing of grinding depth makes contact arc length between grinding wheel and the workpiece increase accordingly, and results in the number of grinding abrasive grains increasing, thus grinding force also increases accordingly.
The length of trajectory of a grain in down-grinding is shorter than that in up-grinding; and the average undeformed chips cut by a grain in down-grinding is thicker than those in up-grinding.
The reason is that in the process of grinding, abrasive grains cut into the workpiece surface to extrude and score the material that makes the material flowing to both sides of abrasive grains.
There are a large number of black small particles stayed on the workpiece surface, which is detected as iron oxide by PHOENIX-60S EDS.

Analysis suggested that making the weak reduction atmosphere at the grain boundary may decrease the grain-boundary resistivity.
Introduction Extensive studies concerning the PTCR BaTiO3 ceramics focused on their electrical properties and the effect of microstructure and composition of grain-boundary on the PTCR properties [1,2,3], as well as a number of applications have been made by using its unique property, such as heaters and thermal sensors in the early days, and more recently, overcurrent regulators of low-power circuits.
Several coarse grains about 10µm in size exist in a fine-grained matrix about 1µm in size about b, and the suface of the coarse grains is not very smoothly, and by increasing the sintering temperature the large grains have grown very well, meanwhile the rt risistivity of the sample is not increased visibly, which have made out in Fig.3.
It is perhaps that the phase of Barium lead has been synthesized outside the BaTiO3 grains.
So if the grains of sample have grown entirely, the rt resistivity of PTCR will not be improved.

Journal Title and Volume Number (to be inserted by the publisher) 3 In this paper, all studies are focused on the formation of the grain size, the volume fraction recrystallised and the subgrain size.
Recrystallized grain size and equivallent strain The predicted recrystallized grain size and the subgrain size corresponded well with the experimental measurement along the tranverse direction, as can be seen from figure 2 and 3.
It is easy to see from figure 2 that the difference between the calculated subgrain size at the centre 0.15 0.2 0.25 0.3 0.35 0.4 0.45 0.5 0 1 2 4 5 Distance to extrudate centre (mm) Recrystallized grain size (mm) 2.0 2.5 3.0 3.5 4.0 4.5 5.0 Equivelent Strain Grain size (predicted) Equivalent strain rate Grain size (experiment) 430 435 440 445 450 455 460 0 1 2 4 5 Coordinate r(mm) Temperature(C) 2.1 2.2 2.3 2.4 2.5 2.6 Subgrain size(um) Temperature Subgrain size( predicted) Subgrain size (experiment) Journal Title and Volume Number (to be inserted by the publisher) 7 (2.27 mµ ) and the experimental measurement (2.22 mµ ) is no more than 0.3%.
From figure 3, the recrystallized grain size shows a sharp decrease at the surface of the extrudate, and it is easy to see the recrystallized grain size is in inverse proportion to the equivalent strain.
Journal Title and Volume Number (to be inserted by the publisher) 13 3.

Microstructural model for the modification of the ferritic grain size, during the plastic deformation of the specimens.
The grain size measurement was performed automatically, by determining the number of intersections of their boundaries.
The average grain sizes measured in undistorted specimens were between 16.8 and 20.0 μm, hl = hr=ho.
The choice of the measurement zones was made taking into account the criterion of variation of grains elongation.
This process is evinced in the Fig. 7, where the micro cavities pass through the ferritic grains, forming the microcracks

This effect allows those grains more favourably aligned to 'pinch off' the less well-aligned grains as depicted in Figure 1 resulting in a columnar grain structure with crystal orientations reflecting the imposed temperature gradient.
From the initial chill interface nucleation, grain growth occurs with elimination of unfavourable <001> aligned grains in a starter block beneath the casting columnar, multi-crystalline structures are then developed in the casting.
The dimensions of the starter blocks permit a columnar grain growth of 25mm.
Wax assemblies are then shell moulded by a 3-axis automated robot, in a proprietary shell system comprising two prime coats and a number of concrete coats.
The resulting starter block grain structure from the trial moulds was a fine, uniform grain size, across the section, right up to the edge (Figure 9).

It is observed that clear and complete bainite and carbide are mostly located in grain boundary (Fig. 3b).
A large number of micro-cracks are observed in a wide area around the macroscopic cracks (Fig. 4a).
Such micro-cracks are several grains long, largely located along the grain at the triple grain boundary.
They are all located at the grain boundary, especially around the triple grain boundary in the form of grain chain along the boundary.
A number of connected cavities form micro-cracks, as micro-cracks extend and merge; macroscopic cracks take shape.

Optimization of Fine-Grained Concrete Composition in order to Improve the Quality of Units’ Front Surface M.A.
In this article, the results of optimizing fine-grained concretes are given.
Special focus was given to the rheological characteristics of concrete mixture which make the biggest impact on the front surface quality class of units produced from modified fine-grained concretes.
Analyzing the defects in the surfaces and the reasons for their appearance, it is possible to highlight a number of characteristics required to get a high-quality surface.
Full product specifications.” and GOST 26633-2010 “Heavyweight and fine-grained concretes.

Applying an annealing at temperatures between 420°C and 540°C, with 30 minutes maintaining time, allowed the investigation of phase occurred during the crystallization and the estimation of the crystalline grains dimensions. 1.
Treated samples were analyzed by X-ray diffraction in order to determine the nature of precipitated crystalline phases and the crystalline grain size.
Based on the diffraction pattern, by Sherrer’s relation was estimated the size of crystalline grains which were resulted from primary crystallization of amorphous phase.
Crystalline grains dimensions Chemical composition Heating temperature [°C] Grains dimensions [nm] Ni68Cr7Fe3Si8B14 420 46 Ni68Cr7Fe3Si8B14 450 69 Ni68Cr7Fe3Si8B14 480 83 Ni68Cr7Fe3Si8B14 510 239 Ni68Cr7Fe3Si8B14 540 279 Ni64Cr18Si13B5 420 209 Ni64Cr18Si13B5 450 210 Ni64Cr18Si13B5 480 220 Ni64Cr18Si13B5 510 279 Ni64Cr18Si13B5 540 381 It is noted, in the case of Fe containing alloy, the heating temperature situated near the crystallisation temperature leads to a crystalline phase with grain size lower than 100 nm.
Therefore, the presence of iron and thus increasing the number of transition metals contained in the nickel based alloys, increases the glass forming ability and the trend of nanostructuring by devitrifying of the amorphous phase.