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To prevent abnormal grain growth, 0.25 wt% MgO was also added.
Influence of alumina grain size and volume fraction of SiC.
For alumina, the pullout dimensions increased with grain size.
around 2µm, and was independent of grain size.
Inspection of Fig. 2 suggests two sources of the reduction in grain pullout on adding SiC to alumina: (i) a reduction in size of each individual pullout, and (ii) a reduction in the number of pullouts present at any given time.

Then, from each ODF, a new list of discrete orientations is generated, and the ratio between the absolute numbers of entries in these lists is chosen equal to the respective volume fractions of the recrystallized and the deformed grains.
The total number of grains in this new list is chosen to fulfill the standard input for the GIA and CORe grain pool.
The median of the size distribution of the previous grains after a CORe calculation is assigned to the reconstructed grain list as the new grain size.
Generally, the simulated grain structure is consistent with experimental observations with respect to both the recrystallized volume fraction and the grain size.
Acknowledgement This research was carried out under the project number M42.5.09375 in the framework of the Research Program of the Materials innovation and institute M2i (www.m2i.nl).

This method enables the production of ultrafine grained (UFG) materials with grain sizes ranging from ~100 to 1000 nm in bulk.
An average grain size of UFG copper analyzed by TEM was 300 nm.
After a large numbers of stress repetitions in excess of 8×105 at sa = 90 MPa and 2.8×105 at sa = 120 MPa, damaged areas with slip band-like traces were crated at the hole-edges.
This area was composed of slip band-like damaged traces that increased their length and number with further cyclic stressing.
At sa = 240 MPa, on the other hand, the crack paths had numbers of long SBs/shear-cracks extended nearly parallel to the crack paths.

Texture evolution depends on the number and type of slip and twin modes active in each crystal.
Grain shape can evolve differently from grain to grain depending on their anisotropy and orientation and on average grain shape can depend on pass number and ECAE route.
Grain stress and interactions with neighboring grains change with grain shape, which in turn, impact grain re-orientation by changing the number and type of activated systems.
Depending on the route, pass number, and material, there are certain conditions in which grains are calculated to become severely distorted, for example, after three to four passes of route A [32].
The number below each pole figure indicates the number of ECAE passes and the letter indicates the route.

In order to avoid the grain-size effect, the ECAP-processed alloy was annealed to coarsen the grains.
The ECAP implementation results in the formation of ultra-fine grained structure of the alloy with an average grain size of 2.0-2.4 µm.
However, at lower deformation temperatures, the plasticity of the alloy noticeably decreases because of a limited number of the effective systems of deformation.
The averaged grain size of the MA2-1 alloy for the different regimes.
The different routes of ECAP of the alloy result in the formation of ultrafine grained structure with an average grain size of 2.0-2.4 µm.

The macrostructure shows that samples with spheroidal and vermicular graphite show much smaller grain size than the flake graphite sample F.
This shows that, for a similar cooling rate, a larger number of austenite nucleus have developed over the same period of time per unit volume, suggesting that a greater nucleation rate of austenite characterizes the solidification of hypereutectic spheroidal and vermicular cast irons.
Two families of grains of different size are observed, as shown in Figure 2.
Some large grains having a size similar to that of gray iron sample F, and other much smaller grains.
A large number of colonies exist within a grain of the macrostructure, assuming that a grain is a portion of the volume having similar austenite crystal orientation.

It seems that the final size of the colonies at the end of the transformation is correlated to the number of α-alumina seeds in the starting γ-alumina powder.
But the above observations suggest that a grain rearrangement process is coupled with the phase transformation.
Unfortunately, at the end of the sintering, the microstructure is always composed of micrometric grains.
For higher contents, the excess of the dopant has to be rejected to the surfaces and grain boundaries of α-particles which grow at the expense of γ-grains.
To benefit from this effect and with the goal of producing sub-micrometric grain size dense ceramics using isothermal sintering, further work with controlled density of nucleation sites and co-doping to limit grain growth is planned.

The size of recrystallized grains having orientations of the rolling texture was considerably smaller than the size of grains having other crystallographic orientations.
Such grains were, on average, smaller than grains of other orientations (see Fig.4).
The largest average size was recorded for P- and CubeND-oriented grains.
The larger number of nucleation sites in the A6.4 sample resulted in a smaller average recrystallized grain size, 13 µm, compared to that in the recrystallized A3.6 sample, 19 µm (see Fig.4).
Once formed, P and CubeND grains were able to grow to a significantly larger average size than grains of other orientations (see Fig.4).

Mechanical milling can bring about grain refining and change of lattice parameters.
Cu grain sizes are characterized by the peak of the XRD points of the composite.
The peak 1 and 2 of Cu the grain size peak changing with milling time.
After a long time of ball milling, grain was introduced in serious grain distortion, high density defects and nanometer fine structure, grain at high distortion stored energy state and the sintering activity improved which facilitating sintering densification.
For the composites being milled the grain continued to be refined and grains boundaries increase.

After FEG–SEM observations, these overestimates are mainly due to additional intergranular cavitation along grain boundaries.
It is expressed in term of the number of cavities per unit grain boundary area and per unit time and given by: N0=α'εmin with α'=Naεfin , Na=dgNmπdH (2) For various stress and temperature values, the parameter α' is determined using the image processing software of FEG-SEM micrographs which allows us to measure the area fraction of creep void and the cavity size distributions.
Ten FEG-SEM images (about 250 observed grains) with magnification X500 were analyzed to determine the number of cavities per unit area of polished section, Nm.
The number of cavities per unit grain boundary area, Na, was then deduced using Eq. 2. with dg the average diameter of austenitic grains and dH the harmonic mean of intersected cavity diameter.
The upper and lower bounds of the time to failure can thus be predicted by: 0.301 h(α)kbTΩDbδ∑n2/5ωf0.5164N03/5≤ tf≤0.354 h(α)kbTΩDbδ∑n2/5ωf2/5N03/5 (3) with Ω the atomic volume (1.21·10-29m3 [6]), h(α) the factor which depends on angle formed at the junction of a void and the grain boundary (0.697 [6]), Dbδ the self-diffusion coefficient along grain boundaries times the grain boundary thickness δ (Db°δ = 7.7·10-14m3s-1 and Qb=159kJ/mol [6]) and ωf the critical area fraction of cavities in grain boundaries (0.04 [7]).