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The powder met the requirements, with a maximum of 1 % of the particles smaller than 45 µm and 1 % larger than 150 µm, with only a negligible number of particles not meeting the sphericity criteria.
The caterpillar layers are formed by elongated grains flanked by smaller equiaxed grains, with segregation evident within these grains.
Segregation of Cr and Ti on the grain boundaries is due to their higher diffusion rate in these areas.
However, the microstructure images obtained by SEM and EDS analysis show a significant segregation of Cr on the grain boundaries and a gradual segregation of Ti, while Nb remains inside the grains.
Discussion So far, only a limited number of studies have been carried out dealing with the production and processing of multi-element alloys from alloy powders and subsequent printing by the DED method.

The coatings, which consisted of nodular grains having microcracks and pits, had either an amorphous or a microcrystalline structure.
Hence, a number of factors for successful trivalent chromium plating are currently being investigated [1-3].
Both inter- and trans-granular cracks are seen on the nodular grains shown in Fig. 1(a).
Numerous, fine oxide grains formed along the contour of the original coating surface (Fig. 3(a)).
The oxide layer with a thickness of about 8 µm consists of numerous, fine oxide grains.

The sintering was performed in vacuum of 10-6 bar for 2 h at 1050oC and 2 h at 1370oC producing 99% of theoretical density pins with an average grain size of 1,19±0,67mm.
Subsequently it was sintered at 1600oC for 4 h which have led to fully dense microstructure with 2,5±0,5mm average grain size.
The superficial roughness Ra of the disc was ± 0,25mm and the pin in the order of the grain size.
One possible source of systematic errors would be caused by differences in wear tracks diameter and consequent difference in frequency and total number of friction cycles.
The groove observed was covered with a layer of very fine wear debris, and the removal of this layer by cleaning uncovers the loss of entire grains by intergranular fracture as shown in Figure 3 (d).

Zr significantly diffused into TiN grain boundaries.
The results also suggested that the formation of metal–oxide in TiN grain boundaries significantly improves the barrier performance.
This decrease is attributed to the grain growth and defect annihilation of the Cu layer during annealing because the sensing current mainly represents the status of the Cu film.
After annealing at 750℃, the intensity distribution of oxygen starts to spread out evidently.Though N2/H2(10%) ambient can reduce the oxygen content in the Cu/ ZrN/Zr/ZrN /Si structures, a considerable number of oxygen atoms might locate interstitially or stuff at the grain boundaries of the ZrN/Zr matrix.
As a result, the fast diffusion paths of Cu along grain boundaries are suppressed efficiently.

However, microscopically each grain which can be considered as a single crystal has its own anisotropy.
A large number of single crystallites provide an overall material property which is the integration of the contribution from each grain.
Grain orientation and size distribution of ferroelectric ceramics in the microscale range were examined by EBSD technique, in which Kikuchi patterns were collected by the CCD camera attached to the FEGSEM specimen chamber.
If the grain structure is too fine the use of maximal accelerating voltage is inadvisable due to overlapping diffraction patterns collected from neighbouring grains.
The Zr and Ti decreases and the lead content increases at the grain boundaries.

Motivation The number of hybrid lightweight structures made of light alloys like aluminium or titanium shapes the development of future vehicle concepts.
The grain sizes show no uniform distribution and their size varies greatly.
It shows a nearly constant grain size and low elongation, Fig. 2 b).
The grains of cp-Ti are in the initial state predominantly in a globular form, the average grain diameter is about 50 µm.
The average grain diameter of the bimodal structure is about 2.5 µm.

Fig. 3 shows the cycle number dependence of the discharge capacities of the Mg2Ni0.6M0.4 (M= Cu, Co) alloys.
Fig. 4 elucidates the relationship between the discharge capacities of the Fig.3 Evolution of the discharge capacity of the as-cast and spun Mg2Ni0.6M0.4 (M=Cu, Co) alloys with cycle number: (a) M=Cu , (b) M=Co alloys and the spinning rate.
The enhanced discharge capacities of the alloys is ascribed to the refined grain by the melt spinning in the light of the grain boundaries possessing the distribution of the maximum hydrogen concentrations [8].
The enhanced hydriding kinetics is principally ascribed to the refined grains by melt spinning.
The huge number of interfaces and grain boundaries available in the nanocrystalline materials provide easy pathways for hydrogen diffusion, which accelerates the hydrogen absorbing process [10].

During sintering process, atomic diffusion was involved completely and also the re-crystallization and grain growth.
A decreased in amount of AIN results in a greater density and grain growth [4].
It is observed that AIN was required at certain amount to influence the decreasing of porosity and the number of grain boundaries.
From the powder microstructure, it shows that sintering increased grain growth.
In observing AIN peak, there was decreasing of AIN number by reflecting the increasing of AIN percentage in mixture.

Frozen state, containing a large number of ice crystals, the local folder 5 ~ 10mm thick layer of ice.
(3) garden gravel: brown, medium density - dense, saturated, the maximum particle size of 80mm, containing about 10% of fine-grained soils, gradation, (4) sandstone: completely weathered to strongly weathered, was gravel-like.
(3) garden gravel: brown, medium density - dense, saturated, the maximum particle size of 80mm, containing about 10% of fine-grained soils, gradation, (4) sandstone: completely weathered to strongly weathered, was gravel-like.
Frozen state, containing a large number of ice crystals, the local folder 5 ~ 10mm thick layer of ice.
Park gravel: brown, medium dense - dense, saturated, maximum particle size of 80mm, fine-grained soils contain about 10% of the general gradation sandstone: weathering ~ strong weathering was gravel-like.

Consequently, a large number of theories have been developed, so that one can hardly give an exhaustive list of them.
The number of variants N depends on the order of the symmetry groups of the parent austenitic phase and of the child martensitic phase.
So, the total phase strain of a grain is
Dependence of the irreversible strain increment due to one thermocycle under constant stress 50 MPa on the thermocycle number.
Dependence of the aggregate irreversible strain due to thermocycling under constant stress 50 MPa on the number of thermocycles.