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The reason for the analysis was a sudden operational defect in a number of the coupling segments of a furnace conveyor belt.
The structure in both the directions is formed of polyhedral austenite grains and carbides precipitated both inside the individual austenite grains and on their boundaries.
As in the previous case, the structure is formed by polyhedral austenite grains with a portion of carbides precipitated inside the individual grains and on their boundaries.
The structure is formed of austenite with a large amount of M23C6 carbides precipitated both inside the grains and on their boundaries
- Generally, carbides precipitated on the grain boundaries are considered as completely undesirable, because they significantly reduce the content of Cr in the austenitic matrix near the grain boundaries.

Under dynamic loading failure can occur by a variety of mechanisms depending on the material constitution and state of stress, temperature, rate of loading and a number of other variables [5].
This could be due to recrystallization and grain growth caused by a rise in temperature above the recrystallization temperature.
At a distance of 3.6 mm away from the entry, deformation of the grains was observed (Fig. 4b), but no grain coarsening was seen which could be due to lower strains and lower temperature.
At a distance of 5.8 mm away from entry point severe deformation of grains was noticed (Fig. 4c).
A demarcation between deformed grains close to projectile target interface, and the non-deformed grains of the target can be seen in Fig. 4c (shown by arrows).

For abrasive grains often wear dominates brittle fracture, which is due to the characteristics of the material grain. [1, 2, 6] During the wearing of the wheel cutting surface can be observed two periods.
The first period is characterized mainly by breaking off or extracting (cleavage) of separate abrasive grains.
The surface of the workpiece is characterized by a number of depressions Zv and protrusions Zp.
Increasing the size of the the cutting force is given by increasing sharpness of grains blade and increasing quantities of grains in engagement through dressing.
By assumption these forces increasing with greater dressing value, that for wheel meant increasing sharpness of grains and increasing quantities of grains in the take.

Number of supplementary vacancies can arrive at a value which corresponds to the density of vacancies in temperatures near the materials melting temperature.
Some porosities, presence of second phase in copper grain boundaries, small alumina particles inside the grains.
Some porosity, presence of second phases inside copper grains (Ni and Al2O3 particles).
Presence of silver second phases distributed in copper grain boundaries.
(a) Presence of some porosity (scale = 50mm); (b) nickel and silver second phases in copper grain boundaries and inside the copper grains (scale = 10mm).

As shown in Fig.2 and Fig.3, the number of inclusions in the club head which close to the sectional parts in the lapsed drill string is very large.
Observed along the thickness direction, close to the inner can clearly see that the friction welding deformation flow line, and more carbon-poor bainite in the organization; the grain size of the organization is smaller, and the amount of carbon-poor bainite is fewer in the intermediate portion; near the outer, the grain size is finer, the organization is tempering sorbite.
Carbon bainite is a lower hardness of tissue, the fewer carbon-poor bainite and finer grain size, the higher hardness, this result is consistent with the preceding test.
Fig.3 shows the number of inclusions is fewer which are closed to sectional parts in lapsed drill string, the organization is tempering sorbite.
We can clearly see the entire fracture surface is covered by the large area of gray leaf spot during observing, site of the gray leaf spot can be observed in many micro cracks, only boss portion of the section can be observed a small amount of plastic dimple, it illustrates that only at this site occurred a small number of the microscopic plastic deformation during drill fracture, due to the influence of gray spots, other parts occurred brittle fracture [4].

These alloys are used both in polycrystalline form and as single crystals, in applications where the reduction of creep strain by elimination of grain boundaries is particularly desirable.
Small hole radii result in strong localization of deformation, so that crack initiation is determined by the deformation response of the relatively small number of grains experiencing high levels of (cyclic) tensile stress.
On the other hand, since the number of stress concentrating features can reach many hundreds, crack initiation is likely to be controlled by the 'weakest link', i.e. the particular assembly of grains that happen to be favorably oriented for cyclic slip and therefore sustain the highest level of damage.
Good qualitative and quantitative agreement is achieved, suggesting that both elastic and plastic components of strain within different grain groups are correctly captured by the model.
Multiple implementations of the microstructure (with the same statistical parameters, such as average grain size and texture) were considered.

Here we review a number of our investigations in the cutting processes of diabase and granite.
The grain breakage pattern observed may occur along the crystalline boundary or/and within a grain.
If the strength of crystalline grain is less than that of the crystalline boundary, the grain will be broken locally.
The fracture chips are formed easier in cutting coarse grain granite than fine grain granites.
Most of quartz grains reveal granular cracks.

Taguchi Method All manuscripts used the Taguchi method, a well-known robust-design technique, provides a comprehensive understanding of the individual and combined effects of various design parameters based on a minimum number of experimental trials.
The microstructure simulation conditions were enlarged grain size 100×100, and initial grain density of 0.01 mm2/mm3.
Figure 6(b) shows the simulation of the grain boundaries, dislocation density, grain orientation, and grain orientation and grain boundaries simulation of Fig. 6. p1, p2, and p3 of the average grain size were 3.52, 2.70, and 2.69 mm2/mm3, respectively, and p2 and p3 produced more detailed grain via the simulation.
And p1, p2, and p3 of the average grain size were 3.52, 2.70, and 2.69 mm2/mm3, respectively.
Therefore p2 and p3 produced more detailed grains via the simulation.

This difference in transition path is a function of material composition and processing, and among which grain size of the alloy has a strong influence.
Numerous reports over the last decade have established that the ECAE processing can be a technique for achieving very significant grain refinement in bulk polycrystalline materials with grain sizes typically reduced to the submicron/nanometer ranges, the levels that are not generally attainable in conventional thermo-mechanical processing.
However, the effect of grain refinement down to submicron levels on shape memory behavior has not been studied and reported in detail yet.
ECAE processing was conducted on these materials in order to elucidate the effects of grain refinement on transition temperatures.
The process can be repeated a number of times.

In the as-received condition the investigated steel was characterized by fine-grained microstructure of tempered bainite.
On grain boundaries there were also single large carbides occurring.
M23C6 carbides were nucleating on grain boundaries of former austenite and rarely on the boundaries of bainite packets.
Precipitations of MC (MX) were identified inside the grains of bainitic ferrite as well as inside the laths in packets.
In some areas the number of precipitated carbides was so big that they formed chains or the so-called continuous grid (Fig. 4).