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The lattice preferred orientation (crystallographic texture), grain shape preferred orientation, grain size distribution and grain interlocking were investigated (on-site analysis from building facades and laboratory tests) to study the combined effect of gravity, daily thermal cycles and moisture on the decay of marble properties, and particularly on the bowing phenomenon.
Neutron diffraction patterns were collected in the range of 4° to 163° using wavelength of 1.62 Å with sample spinning to reduce effects of texture and obtain better grain statistics.
Due to poor grain statistics, known from earlier trials, the experiment involved not just the standard 3 perpedicular (normal) directions but many more.
For dolomite, due to its smaller volume fraction and weak diffraction signal, the number of directions was cut to 65 while measurement time incresed to 80 sec.
On the other hand, smaller natural temperature variations but in much greater numbers during long periods of time might result in even greater accumulated damage, as shown by some historical examples (for example, see Fig. 1).

High heating rates can be obtained [11] and, if precisely controlled, the grain growth is limited [12,13].
Literature data on the densification behaviour and grain growth of TZP based materials during SPS is limited [14,15].
In addition to ZrO2 and TiC0.5N0.5 grains, elongated hexagonal Al2O3 crystals are observed in all the composites examined.
Figure 4 shows a selected number of these XRD scans for materials with different TiC0.5N0.5 starting powders, different yttria content and different powder processing routes.
Substantially shorter radial cracks originating at the corners of the HV10 indentations in the high toughness grade are compared with those of a number of other grades in figure 7.

The criteria to reconstruct the subgrains of the deformed structure were defined by setting a grain tolerance angle of 2º and defining a minimum pixel number in a subgrain.
These conditions were determined by assuming that a misorientation of 2º is the minimum angle that can be resolved with sufficient accuracy under the given experimental conditions, whereas the requirement of a minimum number of pixels per subgrain is intended to obtain a normal distribution of subgrain sizes without an anomalous peak at the very low edge of the distribution which can be attributed to misindexing of scattered individual pixels for deformed or not recrystallized areas of the microstructure [9].
Lee et. al. explained this behavior by combining the theory of oriented nucleation and the orientation inhibition or orientation pinning mechanism suggested by Juul-Jensen [13] and Engler [14], respectively, i.e. the boundary mobility of recrystallized grains is enhanced or inhibited due to the misorientation relationship with neighboring deformed subgrains.
For Ti bearing IF high strength steel, as shown in Fig.6b and 6c, the grains, of which the individual size is two times larger than the sample average, are strongly dominated by the {111}<110> component, and among the grains with the size under average the {111}<112> component is prevailing, which is compatible with the hypothesis of a faster growth rate of the recrystallization nuclei of the {111}<110> component of high angle grain boundaries for neighboring deformed matrix.
The {111}<112> component is a major one for both the grains with two times larger than the sample average and the grains less than the sample average, which may be attributed to the higher tendency of the segregation of P or B because the segregation of solute elements has a significant effect on the mobility of boundary [15] and Ti-Nb bearing IF high strength steel has higher contents of solute P by the suppressed precipitation [12] of such precipitates as FeTiP due to the lower Ti content.

An approach involving the design of experiment was employed to minimize the number of experimental runs, which invariably eliminates trial-by-error associated with traditional experimental methods.
It can compact the powders to nanostructure ultra-fine grains, near-net shaped profile void of segregation with high densification capable of producing high structural bond that serves as barrier to coarsening of the grains [21,22].
A linear regression model shown in Eq. 1 was chosen as the applicable model based on the number of layers [27,28].
A number of 5 indentations was performed on each sample to ensure accuracy of the hardness data collected. 3.
Dong, Powder metallurgy route to ultrafine-grained refractory metals, Adv.

Numbers of automotive part involve rather complex shape which includes forming of sheet in several directions.
Experimental Procedure Tests for mechanical property and grain structure.
The grain structure of SPFH590 was observed on the cross section of sheet parallel as well as transverse to rolling direction using optical microscope and scanning electron microscope.
The fine grain of 5 mm average grain size was found.
Therefore, fine grain hardening is shown to be one of a mechanism to increase the strength of material.

Strain (ε), numbers of crystallites (CN) and dislocations (δdis) These parameters (ε, CN and δdis) are generally used to complete the structural characterization of the prepared CuxZnyS thin films.
In the first model, the effect has been described in terms of the propagation of deformation through the grain boundary, which is caused by the dislocation pile-up against the grain boundary.
The work-hardening model is based on the fact that, at a given strain, a higher density of dislocations is accumulated inside the grains as the grain size decreases.
On the other hand, when the deposition time increases, the grain boundary decreases, which subsequently reduces the scattering of carriers at the grain boundaries and the deformations.
Li, Petch relation and grain boundary sources, Trans.

Despite the appearance of a number of publications on the study of the structural features and properties of metals obtained on the basis of 3D printing technology, there are currently no such studies carried out in this work [14-15].
Results and Discussion The structure of steel 08Mn2Si, obtained on the basis of 3D printing, is similar to the structure of steel in the rolled state after annealing and has a grain size of about 16-48 microns, a grain size difference is observed (6…8 mark grain size).
The structure of 07Cr25Ni13 steel, obtained using 3D printing technology, has a pronounced dendritic structure, the grain size is 80-100 microns.
Conclusions The structure of 08Mn2Si steel, obtained on the basis of 3D printing, is similar to the structure of steel in the rolled state after annealing and has a grain size of about 16-48 microns, there is a grain size difference.
The structure of 07Cr25Ni13 steel, obtained using 3D printing technology, has a pronounced dendritic structure, the grain size is 80-100 microns.

Saturation at 200 °C is probably due to the balance between the number of atoms arriving at the substrate surface and the number of atoms bolting out from the substrate surface by thermal desorption, and also due to lateral growth as the temperature increases.[7] Since the surface mobility of a particle is limited at a low temperature, the growth rate would be higher than that at a high temperature.
The grain size increases with temperature and the surface roughness decreases.
But the grain size and surface toughness is similar above substrate temperature of 200 °C because of the balance between the number of atoms arriving at the substrate surface and the number of atoms bolting out from the substrate surface by thermal desorption.
This result is due to the low mobility of a particle during film deposition at a low substrate temperature, which leads the film morphology consisting of tapered crystallites separated by voids as a result of inter-grain shadowing.

However, the number of commercially available Mg alloys is still limited especially for application at elevated temperature [3].
The poor cold rolling response of Mg is generally attributed to its hexagonal crystallography and the basic symmetry of hexagonal close-packed (HCP) crystals has the effect of limiting the number of independent slip systems and making twinning an important deformation mechanism [4].
A quick examination by etching in a NaOH solution occasionally revealed a few very small stray grains on the surface, but they were always removed from gauge section during machining process.
Results and Discussion Observation of the initial microstructures of pure Mg, Mg-0.1Y, Mg-1Zn-0.5Y, and Mg-0.1Ce alloy ingots, revealed very coarse grain structure.
In the case of alloys containing rare earth elements, some intermetallic precipitates are observed along grain boundary and in grain matrix.

Mo acting as a barrier impeding grain growth during re-sintering at750◦C.
Although after re-sintering the grain size is increased, it is still regarded as quite small, refined and homogeneous.
This decrease is mainly due to the not obvious grain growth in the process of re-sintering.
Fig. 2 SEM images and EDS patterns of samples after repressing and re-sintering: (a) SEM images of Cu-3wt. % MoS2; (b)SEM images of and (c) EDS patterns of A phase in Cu-3wt. % MoS2-7wt. % Mo Tab.1 The properties of samples in each step of repressing and re-sintering Sample number Density [ g/cm3] Electric conductivity [%IACS] Micro hardness [HV] First sintering Re pressing Re sintering First sintering Re pressing Re sintering First sintering Re pressing Re sintering 1 7.86 8.25 8.28 67.3 77.8 80.2 51.3 93.1 88.6 2 7.79 8.06 8.10 42.7 54.4 57.3 90.8 123.1 119.1 Electric conductivity is increased due to the higher density.To obtain better physical and mechanical properties, higher density and unconspicuous grain growth is very necessary.
corresponding powders with 3wt. % MoS2 and 7wt. % Mo Tab.2 Properties of samples prepared by two kinds of techniques Sample number Density [g/cm3] Electric conductivity [%IACS] Micro hardness [HV] Vacuum hot pressing Repressing and re-sintering Vacuum hot pressing Repressing and re-sintering Vacuum hot pressing Repressing and re-sintering 1 8.41 8.28 80.6 80.2 95.9 88.6 2 8.18 8.10 63.8 57.3 127.7 119.1 Summary The Cu/MoS2 composites with homogenous and dense microstructure and higher mechanical properties have been prepared by vacuum hot pressing technology.