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As a result, small grain size is achieved by adding cubic carbides in the starting powders so that the WC grain growth is inhibited during sintering.
The introduction of inhibitors into WC-10%Co cemented carbide caused that the hardness and TRS are drastic fluctuations in the value of number.
It is obvious that the average grain size of the alloys with VC, TaC and NbC are less than that of the Alloy 1#, in which no grain growth inhibitor is added.
Meanwhile, The WC grain growth of the WC-10%Co powders during vacuum sintering occurs by Ostward ripening with dissolution of smaller WC grain and reprecipitation on larger grains in liquid Co.
WC grain growth and grain growth inhibition in nickel and iron binder hardmetals [J].

There are two (interrelated) processes leading to change of microstructure: 1) the production of a very high number of dislocations, leading to a high dislocation density, 2) the "fragmentation" of the original crystal grains into much smaller structural elements leading to what is sometimes called "nanocrystalline" material.
This is why they are often called "grains".
For these, the term "non-equilibrium grain boundaries" has sometimes been used [6] ∗ .
∗ After a mild annealing treatment one obtains small real grains surrounded by large angle grain boundaries.
It would be analogous to grain boundary sliding and superplasticity - again with the reservation that no true grain boundaries are involved.

In addition, neighboring grains have different energies and these neighboring grains define the grain size.
According to it, two layers of grains and grain boundary form an inhomogeneous dielectric specimen.
Grain boundaries have low conductivity whereas the grains are more conductive.
It contains different mechanisms related to grains, grain boundaries and electrode contribution.
Nyquist plots at different temperature suggested that conduction mechanism in material was due to the increase in number of grains and thus the resistance.

It is found that the intermetallic compound particles are located along grain boundaries of the equiaxed grains.
The grain sizes of all alloys increase with the holding time mainly because of the coalescence effect between grains.
The grains are very large with a number of liquid phase regions existing inside.
The grain size of this alloy slightly increases with holding time.
Moreover, it is found that the cold-rolling has a strong effect on the grain size, morphology and liquid phase in the α-Al grains of the Mn containing alloy.

The grain size of about 1 µm was obtained in the Zn-0.3 wt.% Al alloy and a relatively coarse grain size of 10 µm was also obtained through a subsequent aging treatment.
According to the internal variable theory of structural superplasticity, the grain boundary characters of fine and coarse-grained materials were different from each other.
There have been an extensive number of reports on SSP in the various classes of materials including metallic materials, ceramics, and amorphous alloy [5-8].
A relatively coarse-grained material with the grain size of 10 µm was also prepared through a subsequent aging treatment of the fine-grained material to investigate the grain size effect.
This result strongly suggests that the character of grain boundary can also be changed with the severe grain refinement.

Abrasive grain was estimated as a sphere with diameter d0.
Spacing of abrasive grain.
If abrasive grains of the number m grind the space between A1 and Am until the Am cuts the same line of B1 cutting, then the average spacing scratch generated by abrasive grain b becomes b =(ω/m)cosθ.
The abrasive grain mesh of the diamond wheel used three kinds of grain numbers; 100, 270 and 500.
The hardness of the diamond wheel is expressed as the strength of a bonding agent supporting each diamond grain.

Bold numbers reveal the exceeding of the minimum requirement from the standard ASTM B348-02 grade 23 for this property.
Boron effects a drastic reduction in grain size as visible in table 1.
These particles act as obstacles for grain growth by pinning of the grain boundaries [8-9].
The fatigue experiments reveal the effects of porosity and grain size.
The numbers in parentheses denote the amount of samples that survived at a specific stress level (run out).

According to literature, the level of grain refining achieved by these processes is very limited (about 5 μm) [6].
A novel processing route of controlled reversion annealing of the heavily cold-deformed martensite in metastable Cr-Ni austenitic stainless steels has been employed resulting in highly refined austenite grain size by a number of researchers [2,10-13].
Moreover, by increasing the ASTM austenite grain size number, the amount of strain-induced martensite is reduced[22].
Short annealing treatment would serve to revert strain-induced martensite (a¢), formed during heavy cold rolling, to strain-free, sub-micron sized austenite grains, which contribute to improvement in mechanical properties (strength-ductility combination) through grain refinement/ grain boundary strengthening mechanism. 3.
Ferreira, Microstructure evolution in nano/submicron grained AISI 301LN stainless steel, Mater.

The application of pressure results in decreasing thermal activation and, thus, in the grows of number of dislocation sources and, finally, in the increase of DSH.
We show that the proposed model not only explains a number of known effects, but also suggests new ones.
One of the ways of increasing the intensity of substructure grain refinement is the increase of its amplitude [6].
As expected, we have some improvement of grain refinement (curve )(ed ), but structure failure has still increased (curve )(eθ ).
Varyukhin: In Ultrafine Grained Materials II, ed.

Introduction It is well known that hexagonal close-packed (HCP) magnesium and its alloys have complicated deformation mechanisms, because deformation twins are activated to supplement the limited number of available slip systems for a homogenous deformation [1,2].
The microstructure and grain size of the solutionized alloy were examined by optical microscopy (OM) and the average grain size was found to be about 90 µm.
The {10.1} and {10.2} grain families, favorably oriented for basal slip, show the soft grain orientation behavior involving stress relaxation, while the {10.0} orientation reveals the hard grain orientation behavior taking on additional load.
The highest strain occurs in the {11.0} grain orientation.
In Fig. 3a, the lattice strains for all five grain orientations are linear up to an applied stress of ~30 MPa, after which the slopes of {10.2} and {00.2} grain families decrease as the grains start to yield.