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Large-scale deformation patterning in geomaterials associated with grain rotation Maxim Esin1, a, Arcady V.
Independent rotations of separate grains/particles can affect the pattern formation by adding the effect of rotational degrees of freedom to the mechanism of instability.
The numbers inside the disks show the angles of rotations in degrees.
It means that the rotations are microscopic (at the scale of the grain size) and do not proliferate to the macroscopic scale.
Viggiani: From grain kinematics to continuum mechanics.

Continuous network of grain boundary which is reason for poor mechanical properties was eliminated.
The homogeneous (grain) micro-structure with high angle boundaries (of some alloys) leads to super plastic forming in FSP.
The grain boundary was not visible in the FSZ in optical as well as in SEM microstructures.
The tensile strength values of FSZ were more for both the tool profiles, for less than 1.5 mm distance between passes, but if it is reduced further, the number of passes increase which results in more cost, tool wear and is more energy consuming.
The grain refinement occurred due to processing; extend of grain refinement was identical for all the parameters, distance between the passes have no effect on this. 2.

Two of them were coarse-grained WC with grain sizes larger than 6 µm and binder fractions of 10 and 15 wt. %.
The other two were fine-grained with WC grains of 0.5-0.8 µm and the same binder fractions of 10 and 15 wt. %.
Two of them were coarse-grained with WC grains larger than 6 µm and binder contents of 10 and 15 wt. %.
The other two were fine-grained, with WC grains of 0.5-0.8 µm and binder contents of 10 and 15 wt. %.
The test parameters were as follows: r = 3 mm, force Fn = 30 N, speed 154 rev/min, number of cycles 20,000 and the diameter of the sapphire ball was 3 mm.

Among the others SiC nano grains (intra- and intergranular), various complex new phases e.g. oxides, oxi-nitrides, carbo-nitrides, etc.
Grain size: The influence of the carbon grain size may be assessed from test results of the G3, G4, G5 samples, containing the same amount of C with increasing grain size.
In case of specimens G2, G4 and G5 the material could have been characterized by a number of cycles belonging to the onset of a steady state, as well as by a related constant value of the friction coefficient.
Inside the applied range of the total sliding distance and applied loads G1 and G3 samples showed no steady-state features, however similar behaviour may also be assumed for the extended number of cycles.
Using graphite additives of finer grain size resulted in better wearing performance of the nanocomposites.

Phases of the composites were mainly WC, W2C, M6C, M7C3 and (Fe, Ni).The WC grains formed in situ had rectangular or triangular shapes with size of 30-70μm.
There are a number of processes to prepare WC-based composites, including laser cladding [1], plasma melt injection [2], consumable electrode in-situ metallurgy [3] and so on.
The size of WC grains ranged from 30μm to 70μm.
Therefore, with further cooling of the melt pool, the Fe-based phase with little W appeared around the WC grains.
WC grains grew up in rectangular and triangular shapes, the size of which ranged from 30 to 70μm.

The phenomena of grain growth has been utilized in material processing for many years.
Briefly, our wish is to become a really active junction of a network including the largest possible number of academic institutions and specialized research laboratories.
From these papers of Cyril Smith we learned of the importance of grain boundary area reduction and the relationship of area reduction to motion by curvature; the importance of dihedral angles; the remarkable result in two dimensions with 120 degree trijunction angles, that the rate of growth or shrinking of a grain depends only on the number of its corners and not on its size or shape, and the importance of particles in slowing or stopping grain growth.
Grain shapes in opaque metals were revealed by fracturing embrittled specimens or in stereoscopic radiography that revealed grain boundaries coated by thin films.
Grain growth was only one field Cyril Smith has blessed us with his insight.

The Method of Creating and Measuring the Printability of Fine-Grained Concrete Valery S.
The Internet contains a large number of pages illustrating the achievements in this field of various research and industrial organizations, among which, with special respect, we would like to mention those belonging to China [6].
Results Evaluation of Printability of Fine-Grained Concrete Mixtures Table 2 shows the results of determining the suitability of fine-grained concrete mixtures of various compositions for printing.
The main results of testing the developed compositions of fine-grained concrete for construction printing are presented in table 3.
The proposed method showed its effectiveness when using different cements of the most popular types and small aggregates that differ significantly in grain composition.

For thin slab production of particulars, in order to prevent the peritectic reaction,C content should be less than 0.065%. (2) Nb was the most efficient grain refinement of elements and precipitation inhibit the recrystallization of austenite during hot rolling process, effectively improved the ferrite core ,and ultimately resulting in grain refinement of ferrite.
Nb had significant precipitation hardening and fine-grain strengthening effect.
Meanwhile, in order to avoid excessively high Nb content mixed grain, Nb content designed for 0.045%~0.050% was appropriate. (3) In addition to Ti in steel , TiCN compounds formed in the high temperature phase refined the grain, O and S in steel also had a strong affinity with Ti to improve the shape of sulfide and significantly improve the toughness of the steel, improving performance and fatigue properties of weld heat-affected zone, Ti content designed for 0.015%~0.030% was appropriate.
（1）improve the beginning rolling temperature Nb has inhibited the recrystallization of deformed austenite, opened before rolling the original dynamics of recrystallization of austenite grain coarsening delay was causing organizations mixed crystals of Nb micro-alloyed steel CSP, so that the promotion of coarse grained austenite recrystallization kinetics was the key to improved steels with microstructural homogeneity.
Grain size was relatively small, the average grain size was 5.0~6.0 μ m.

For irregular TiC grains were in the absence of dislocation migration at room temperature, brittle fracture has to happen in irregular TiC grains under tensile loading, and transgranualr fracture becomes the only fracture mode of TiC through formation, propagation and connection of the microcracks in TiC grains, as shown in Fig. 2 (b).
Meanwhile, TiC-66.7 mol%TiB2 prepared in the current experiment is considered one hypereutectic composite according to the reported literature [7], so TiB2 crystal acts as the primary phase to grow independently from liquid TiB2-TiC, and the boundary of TiB2 platelet is in fact the instinctively-developed surface that is stacked with a number of interfacial defects [4].
Figure. 4 FESEM images of crack propagation paths and fracture surface of solidified TiC-TiB2 composites prepared under the high-gravity acceleration of 2500 g (a) crack deflection around TiB2 platelet (b) bridging and pullout by TiB2 platelet (c) pullout by a number of TiB2 platelets Becher [8] considered that the toughening behavior of crack bridging and subsequent pullout caused by non-cubic matrix grains was analogous to that of the whisker reinforcement, and their contributions to toughening ceramic were closely dependent on radius of the bridging ligament r, interfacial debonding length ldb and pullout length of the ligament lpo, volume fraction (Vpo, Vfb) of bridging and pullout the ligaments participate in.
XRD, FESEM and EDS results showed that the ceramic was comprised of TiB2 platelets as the primary phases, irregular TiC grains as secondary phases, some Al2O3 inclusions and a few Cr-based metallic phases.
As the high-gravity acceleration reached 2500 g, there was the ultrafine-grained microstructure in the current composite with TiB2 platelets smaller than 1 μm in thickness.

Genetic Algorithm and multiple regression analysis were adopted to achieve cutting force predicted model of multi-diamonds fast milling hard-brittle materials with defined diamond grains pattern by single diamond fast milling hard-brittle materials experiments.
Predicted model can afford another study direction for processing analysis of diamond tools, tools making and processing parameters selection from the view of diamond grain practice cutting.
Based on upper methods, extend researches derivates single grain cutting force and general cutting force formula by various mathematical methods [6-8].
In this paper, genetic algorithm and regression analysis were adopted to achieve cutting force predicted model of multi-diamonds fast milling hard-brittle materials with defined diamond grains pattern by single diamond fast milling hard-brittle materials experiments.
Conclusions Genetic Algorithm and multiple regression analysis were adopted to achieve cutting force predicted model of multi-diamonds fast milling hard-brittle materials with defined diamond grains pattern by single diamond fast milling hard-brittle materials experiments.