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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].

The review stresses concepts rather than voluminous facts and a number of theories.
Liquid precipitates form within grains and along grain boundaries during heat treatment.
New forms of grains appear at grain interior while new grains form at grain boundaries.
Brittleness stems from a fairly high ordering energy of the compound, which does not permit enough number of independent active slip systems to operate to fulfill the compatibility requirement of grain boundaries of B2-type crystal structure.
It also leads to reduction of electrical conductivity by reduction of ferrous ion numbers at the octahedral sites.

The experimental results showed that the electric current pulses during solidification changed morphology of dendrites and the equiaxed, non-dendritic grains formed.
The grain refinement and the formation mechanism of non-dendritic primary phase are discussed in this paper.
It is known that the nucleation of the phase is depended on the number and the size of the so1id-1ike clusters in the melt.
It is more intriguing that the grains are globular or non-dendritic in shape.
With the LVECP treatment, the solidified microstructure of AZ91D alloy is modified and the equiaxed, nondendritic grains are formed instead of dendritic

The results show that the mechanical properties of coarse-grained materials are more strongly affected by the current pulses than finer grained material.
In pure Mg, twins formed inside the grains.
Still, the number of twins was very low in comparison to pure Mg.
With the higher current density, similar to pure Mg, wide twins formed inside the grains.
The higher drop in stress in the plastic regime can be explained by the interaction between electrons and the larger number of dislocations.

The coercivity decreased as the number of precipitate decreased and the width of martensite lath increased.
However, some experimental investigations reported the effect of grain boundaries on the magnetic properties.
The magnetic coercivity versus the inverse of the width of martensite lath and number of precipitates.
Degauque et al. [12] noticed that the magnetic coercivity was inversely proportional to the grain size in high-purity iron and they insisted that the grain boundaries could be obstacles to the movement of the domain wall.
Takahashi et al. [13] also showed that the magnetic coercivity was inversely proportional to the grain size in α-Fe metal.

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.

When the temperature further reduces to 100˚C, the β phase continues to extend inside grain, and the lamellar β phase is basically formed inside individual grain.
Cooling to 50˚C, the number of β phase increases dramatically, and the lamellar β phase evenly distributes inside most of the grain.
The main causes resulted from the fact that the crystal defect on the grain boundary was far more than inner grain, and the aluminum atom diffused easily.
So, the β phase would be easier to nucleate and grow on the grain boundary.
The β phase breadthwise nucleate and grow near the grain boundary, and then grows towards the neighbor grains with longitudinal direction.

The original austenite grain boundary, discontinued , finer Lumpy, it is nearly continuous in the grain boundary of austenite.
In pearlite, it is slightly coarse than that in grain boundary.
Grain boundary of original austenite is almost continuous.
VN or VCN continues to precipitate within austenite crystal and number of grains increases: Precipitation at grain boundary, including grain boundary of original austenite, probably also including interface of ferrite or austenite.
In this case, when number of positions for harmonized heterogeneous nuclei will hardly change for ferrite within grain boundary of austenite, dimensions of ferrite grains will be slightly greater at grain boundary of isothermal ferrite austenite, as indicated in Fig 1.

Thus to ensure the network to restore the situation in the application of fine-grained has lower error rate, thereby reducing the distortion of the application distribution.
Thus ensuring the network to restore the situation in the application of fine-grained has lower error rate[2].
b) Random sampling Random sampling is also in N click sampling a point, but will have a less than N random Numbers to decide whether point should be sampling.
c) Packet statistics in sample space of application group When the mes packet goes through the applicationgroup, each sample space will be recorded through the message number.
Thus ensuring the network to restore the situation in the application of fine-grained has lower error rate, thereby reducing the application and distribution of distortion.

Inclusions which located near the prior austenite grain boundary couldn't induce the nucleation of IAF, only the ones inside the prior austenite grain can promote IAF's growth.
Furthermore, prior austenite grain size is also an important factor affecting the nuclei of IAF [4-5].
Utilizing the intergranular ferrite which had outlined the prior austenite grains, we measured the prior austenite grain size, and the statistic histogram is shown in Fig. 5.
The size of prior austenite grain is about 50~70 micron during the three simulated weld thermal cycles.
The grain size would increase as the phase cooling time extend.