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The smaller grain size of the composite microstructure the higher hardness can be achieved.
Conventional vacuum sintering could be reliable and simple technology to produce cermets with average grain size >1 µm, but it becomes quite challenging to obtain submicron grains [4].
To minimize the number of variables hardmetals with same binder volume (24%) and mass (15%) fraction and similar average grain size (<1 µm) will be studied.
Each grain was separated manually by a thin line to avoid errors in the data analysis.
Results and discussion The indentation surface fatigue tests were repeated at least three times for each number of indentation loading cycles, respectively 1000, 10 000 and 100 000.

Although a great number of researches on Al-Cu alloys have been done, little research on improving mechanical property by the centrifugal force field is reported.
This is because with increasing the centrifugal radius and mould rotation speed, grain size decreases, and the variation amplitude of grain size increases [8].
When the dislocation glides from one grain to another, it is hindered by grain boundary resulting in pile-up of dislocation.
The finer the grain size, the higher the grain-boundary density so that the above hindrance role is greater and the casting is harder.
Moreover, the finer the grain size, the more the number of grain.

Hardness measurements were used to investigate the influence of high pressure torsion (HPT) number revolutions on mechanical properties.
The grains were elongated and stretched due to the severe shear strain.
The average crystallite size plotted versus number HPT revolutions Figure 12.
The calculated dislocation density plotted versus the number of HPT revolutions Hardness Figure 13.
Mechanical properties of an ultrafine-grained Al-7.5 Pct Mg alloy.

The purpose of the study is to determine the influence of the type of plasticizers used for water activation on the speed of structure formation and the strength of fine-grained concrete.
However, the availability of such cements in a significant number of cases is significantly limited and requires solving the problem of organizing their search and transportation in sufficient quantities.
The problem lies in the clearly insufficient number of existing methods of calculation, construction and organizational and technological measures to ensure a high rate of concrete hardening.
Aim of Paper The purpose of the research is to determine the effect of ultra-low doses of plasticizers of various compositions on the strength of fine-grained concrete and the rate of formation of its structure.
Shishkin, Research into effect of complex nanomodifiers on the strength of fine-grained concrete.

Introduction Grain refinement is one of the three major technology means of new type alloy, which internationally make traditional material upgrade and create [1] .
The small grain can improve the toughness of the material.
Through its analysis of process parameters, seeking some of the methods and points to improve the preparation of excellent refinement capabilities Al-Ti-B grain refiner, to obtain the desired process parameters.
Time 40min Analyzed in Figure 4 ,Figure 5, Figure 6 and Figure 7, the reaction time was 10min, A striking lack of reaction time, the size and the number of the generated TiAl3 is small; As the extension of reaction time, the size and the number of the generated TiAl3 becomes large, when the reaction time is 40min , TiAl3 assembled partly .
Superheat temperature reached 9300C, the morphology of TiAl3 phases had mutations, a large number of elongated needle appeared.

Grain size distribution, hardness and temperature profiles in the welded zones were determined in order to obtain the relationship between the grain structure and the hardness profile in these regions.
In each alloy, the average grain size in the weld nuggets was identical.
The Vickers hardness numbers of the welded zones in all specimens were measured on a cross-section perpendicular to the welding direction using a Vickers indenter using a 100 gf load applied for 15 seconds.
In all specimens, the average grain size in the weld nuggets was the same.
Microhardness numbers of joints across the mid-sections; (a) 2024, and (b) 5083 alloys.

For the last decade, there have been a number of studies aimed at understanding the kinetics of IGC [3] and exfoliation corrosion [4].
Increasing the 'strength' of a texture means there is a high tendency for grains to orientate themselves with a similar crystallographic orientation as other grains, as opposed to 'weak' texture where the grains orientate themselves more randomly.
A strong texture results in low misorientation angles between adjacent grains.
Therefore, the tendency for the corrosion path to branch off a susceptible high-angle boundary will be reduced if the number of low-angle boundaries is increased, making IGC more directional.
As mentioned above grains will develop a preferred distribution of orientations.

The measurements were done with an accuracy of 0.01 mm and numbers of loading cycles N were registered.
The grains form bands according to the rolling direction: elongated grains of phase α, 5-25 µm wide, and fine grains of phase β, 1-5 µm in diameter.
Fig. 2a shows the specimen surface under Ma = 11.2 N⋅m and the stress ratio R = -1 after a number of cycles Nf = 1753000 together with the final course of the crack about 250 µm in length.
At the fractures, transcrystalline cracks through grains of phase α predominate, but cracks along the grain boundaries are also observed.
The grains form strips arranged according to the direction of plastic working; elongated grains of phase α are to 50 µm in width, grains of phases β and S are fine and their mean diameters are 5-10 µm.

But they are strongly dependence on the number of GP passes and the pressing modes.
However, nearly all of the investigations were focused on the microstructures evolution and grain refinement of the materials.
The results are plotted in Fig. 1 against the total number of passes in GP.
In addition, the decrease in the dimple size should be associated with the grain refinement of samples processed by GP [21-22].
But they are strongly dependence on the number of GP passes and the pressing modes

The acicular ferrite grains formed in the austenite grains were trigged by the intragranular ferrite grain(s) formed around TiN.
The pole figure from the ferrite grain and the particle in Fig. 3(a) show that the (001) plane of a ferrite grain is parallel to the (001) plane of a TiN, and the (011) plane of a ferrite grain is parallel to the (001) plane of a TiN.
Fig. 4 shows an inclusion surrounded by a number of ferrite grains corresponding to Fig. 2(a).
The acicular ferrite grains formed in the austenite grains were trigged by the ferrite grains formed around TiN.
The acicular ferrite grains formed in the austenite grains were trigged by the intragranular ferrite grain(s) formed around TiN.