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More specifically the amount of elements in the transverse and longitudinal faces was varied whilst keeping the total number of elements constant.
The grains in a polycrystal are irregular shaped and have different sizes.
Such a microstructure is difficult to reproduce in a finite element mesh, particularly because it requires a large number of elements to represent each grain and, at the moment, the computational effort required makes this impractical.
Ultimately, this deformation is imposed on a grain by its nearest neighbours.
Although CPFEM models the discrete distribution of grains and hence the constraint of neighbouring grains on a grain's response, changing the misorientation of nearest neighbours does not change the macro response, mean intergranular strains or the scatter of around the mean.

To this end, established grain-refining techniques such as the use of chemical grain refiners and electromagnetic stirring can be employed [1-3].
However, because of the applications for which they are used, these structures are subject to fatigue, so the design should consider the statistical distribution of the fatigue resistance that the material must have for a given number of cycles.
Grain size, shape factor and porosity for all the conditions studied.
Eckert, Grain size control in Al-Si alloys by grain refinement and eletromagnetic stirring, Journal of alloys and compounds. 487 (2009) 163-172. https://doi.org/10.1016/j.jallcom.2009.08.032
[12] ASTM E 112-13, Standart test methods for determining average grain size. (2013)

The adjusted parameters are grinding depth and abrasive grain size.
Relation between surface residual stress and abrasive grain size.
Fig.5(c) shows the relation between surface residual stress and abrasive grain size.
The surface residual stress of nano-ZTA under DG increases with abrasive grain size.
Under same grinding parameters, effective grinding depth for DG with coarse abrasive grain is larger than that with fine coarse abrasive, and the number of larger abrasive grains on unit area is less than the number of smaller abrasive grains on unit area, so coarse abrasive grains have more pressure than fine abrasive grains under constant grinding pressure on unit area, as a result, the value of residual stress becomes larger.

But if the matrix, namely binder phase, is well-distributed around tungsten grains and the strength of W-binder interface is high enough, initial crack propagating through the binder phase occurs along with the cleavage in W grains.
Seen in Fig. 4 (b), both the number and size of the pores in the as sintered specimen are actually small.
Nevertheless, the average W grain size coarsens slightly.
As known, W-grain growth becomes more noticeable at the high sintering temperature.
Furthmore, higher sintering temperature makes the W-W grains more effectively seperated by the binder phase and reduces the number and size of pores.

At a grain size of ~275 µm (i.e.
As ∆K increases, the number of Si particles on the fracture surface increases, reflecting the crack's preference for advancement via Si particles.
At high ∆K, when the plastic zone is large and the cumulative strain damage is high, the number of fractured Si particles increases even in the modified structures, and cracks propagate via both debonding and fracture mechanisms.
The behaviour of Al-Mg cast alloys is also related to the grain size.
Fracture toughness (~20 mMPa ) of the small grained material is slightly higher than that of the large grained material due to the ductile monotonic failure at grain boundaries associated with the upper Region III.

CPD can provide a large number of defects in the steel, suggesting that there exist a large number of defective grain boundaries and dislocations despite under boronizing temperature.
Therefore, the boron diffusion can be enhanced along the grain boundaries and dislocations because of a smaller activation energy compared to that for lattice diffusion at boronizing temperature.
The driving force for boride formation may be also enhanced when there are a large number of defects in the steel.
However, the structures with plastic deformation store a large excess energy in the grain boundaries and grain interior in the form of non-equilibrium defects, which constitutes an extra driving force for boride formation [7].
This arises because CPD can provide a large number of defective grain boundaries and dislocations in the steel, which results in accelerating boron diffusion and being helpful to form borides at boronizing temperature.

The second microstructure (figure 4) observed after annealing at 975°C shows a partially transformed microstructure which is characterized both by smaller equiaxed grains and larger irregular grains.
It is assumed that the former are recrystallized ferrite grains whereas the latter are transformed ferrite grains.
This single layer of surface grains represents a specific texture which is dominated by <100> and <110>//ND fibres grains.
This is not only true for the sold/vapour interface but also for the grain/grain interfaces in the surface monolayer.
In order to fully benefit from the potential of this degree of freedom a number of obstacles still need to be overcome.

Mechanical fracture parameters of fine-grain concretes with zeolite: Effect of composition and origin of cements ŠIMONOVÁ Hana1,a, SCHMID Pavel2,b, KERŠNER Zbyněk1,c and ROVNANÍKOVÁ Pavla3,d 1 Brno University of Technology, Faculty of Civil Engineering, Institute of Structural Mechanics, Veveří 331/95, 602 00 Brno, Czech Republic 2 Ditto, Institute of Building Testing 3 Ditto, Institute of Chemistry asimonova.h@fce.vutbr.cz, bschmid.p@fce.vutbr.cz, ckersner.z@fce.vutbr.cz, drovnanikova.p@fce.vutbr.cz Keywords: cement, concrete, zeolite, fracture test Abstract.
This paper introduces results of fracture experiments on fine-grain concrete specimens prepared from CEM 42.5 R Portland cement of different origin (five Czech Republic localities: Mokrá, Hranice, Radotín, Prachovice, Čížkovice), with natural zeolite admixture.
Material, test specimens, and fracture tests Test specimens with nominal dimensions of 40 × 40 × 160 mm of fine-grained concrete, whose composition was based on the standard EN 196-1 Determination of cement strengths, were manufactured to determine the values of mechanical fracture parameters.
It allows, via adjustments, a number of variables to be monitored (in addition to the estimated value of the static modulus of elasticity Ec of the approximately linear introductory passages of the P–d diagram) that quantify material resistance against crack propagation elements in different ways.
Conclusion Although cement CEM I 42.5 R made in various cement plants meets the requirements of EN 197-1, there were found differences in the composition and in resulting mechanical and mechanical fracture properties of fine-grained concretes.

In the wheat and oats grains irradiated at doses of 0.3 and 0.7 kGy this indicator was 1:6.7-1:37.3.
It is worthwhile noting that a dose of 700 Gy does not compromise the baking quality of the grains.
Between days 2 and 21 after the irradiation at a dose of 25 kGy, QRT titres in the grains (wheat and oats) ranged from 1: 21.3 to 1: 53.3, with the peak values recorded on days 7-21 versus 1: 0.7-1: 2 in the non-irradiated grains.
Significant numbers (37.5 ± 5.5) of cocci and bacilli, mostly gram-positive, were detected in the samples of non-irradiated meat on day 20 of storage.
The results of our studies are in agreement with the data obtained by a number of foreign researchers [2, 6, 7].

The bridge-link phenomena induced by the flaky grains occurred in three-point bending test.
The bridge-link phenomena induced by the flaky grains are shown in Fig.9.
0.025 0.050 0.075 0.100 Load / kN Displacement / mm 10µm 5µm 5µm From Fig.4, we may see that there are a number of plate-like Ti3AlC2 grains which consisted of many thin slices distributed in the sample.
Transgranular crack and grain torsion may be observed in the compressive sample fractured at 1100°C (Fig.6), and obvious plastic deformation occurred at 1100°C.
The bridge-link phenomena induced by the flaky grains occurred in three-point bending test (Fig.9).