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Low binding energy of 0.098 eV and large output intensity indicates a large number of weak hydrogen traps such as the crystal lattice.
During the annealing at the second cycle, hydrogen was redistributed from clusters to the pores and free volume of a larger number of clusters became “opened” for positrons.
Islamgaliev, Vacancy clusters in ultra-fine grained metals prepared by severe plastic deformation, J.

The use of laser drilling in manufacturing industry can be attributed with a number of undesirable defects including recast layer, heat affected zone, oxide layer and spatter.
The structure before the treatments (Fig. 1) is irregular, with pores and grains having boundary decohesion.
Acknowledgment This work was supported by the Ministry of Science of the Republic of Serbia under contract numbers TR-35040 and TR-34015.

The properties of the wires depend thus on a number of technological treatments applied in their production.
The images for the wires obtained from the CCR wire rod show the typical materials of fibrous grain structure with an insignificant number of separations.

Traditionally the weight reduction is reached by using light, but insufficient strength materials, for which a limited number of welding methods is applicable.
Parameter 1561 (АМg6) alloy R-1580 Al-Sc alloy Variance Mass of Al-constructions, ton 19 15.2 3.8 Cost of Al-alloy constructions, $ 19*5360=101 840 15.2*5448= 82 809.6 19 030.4 Number of the vessels in the program, units 35 35 - Total cost of the Al-alloys for the program, $ 3 564 400 2 898 336 666 064 Indirect economic effect.
Kodzhaspirov, On Dynamic Superplasticity of Aluminum Alloys with Initial Varying Grain Size Structure, InDefect and Diffusion Forum. 385, (2018), 78-83

The FSW process allows the joining of a large number of similar and dissimilar materials which are difficult or impossible to join by other processes.
It can be seen that ultrasonic treatment leads to a significant improvement in the fatigue properties of the friction welded joint, characterized by a disposition of the curves at a higher number of cycles [14].
While in ZIT at conventional welding (figure 3.a) several areas with large grains can be detected, at the one with ultrasonic assistance, the distribution is substantially finer (figure 3.b).

The equation 8 is implemented as the following integral (9) where: t - time of deformation, - time increment, - the values of the strain rate in the current time, m – index number of time step during numerical integration along the flow line.
Results of simulation of extrusion process (No. - number of the variant, V - extrusion velocity, t - temperature of the billet, tmax - maximum value of temperature in a billet during process, D - value of the fracture criterion, P – load).
Fig. 4 shows MgCa08 sample composed of Mg matrix (large equiaxial grains that crystallize in hexagonal hcp lattice) with homogeneously dispersed particles of Ca (black dots with white surroundings in Fig. 4b).

Based on findings in studies and research carried out by various foreign authors, it is evident that active fine-grained ingredients can be used as modifying binding components to improve the heat resistance of composites based on a silicate matrix.
At this point the formation of a larger number of cracks, although insignificant in width, already appeared at a temperature of 800 °C.
The visual assessment of the surface identified an increased number of narrow cracks in specimens exposed to temperatures of 800 °C and 1,000 °C.

Different cutting tools such as PCBN, ceramic, coated carbide and fine-grained carbide were used.
The sampling length and number of spans were set to be 0.8 mm and 5, respectively.
The S/N ratio η for the resultant cutting force can be calculated as follows: (1) where n is the number of repeated test and Frj is the average value of the resultant cutting force Fr in the jth test.

Their distribution depends strongly on the defects such as vacancies, dislocations and grain boundaries in the crystals.
Diffused or implanted element & temperature Total number of 57Fe to obtain one spectrum 57Fe depth profile & concentration Time after diffusion or implantation Radiation fluence Charge states of interstitial 57mFe Charge states of substitutional 57mFe Reference (1) 100keV 57Fe implanted RT&1073K 2×1015 /cm2 R=100nm △~100nm 2×1020/cm3 △t ~ days tmeas~100ns 57Co source /3.7GBq 5×106 g/cm2s 0 0 Present work (2) 57Fe diffused RT-1273K 1×1016 /cm2 D=1-500 mm △0.1-200 mm 1017-21/cm3 △t ~ weeks tmeas~100ns 57Co source /3.7GBq 104-6 g/cm2s 0/+1/+2 -1 /0/+1?
A depth profiles of 57Fe impurities and the numbers of collision events are shown in Fig.1 (b) as function of depth, which were estimated by a SRIM simulation [21] for the case of 100keV-57Fe+-implantation at room temperature.

Product development method [2] After the project is contoured, having established the main high level characteristics such as number of parts, life expectancy or price goal, it is time for the development team to define the product through the use of an analytical approach, translating the product goals into basic requirements to be accomplished (Fig. 2).
On grained surfaces the defect is less visible, but even here defects can be unacceptable.
Acknowledgement This work is supported by the Romania’s Operational Program for Human Resource Development (POSDRU), financed from the European Social Fund and the Romanian Government under the contract number POSDRU/159/1.5/ S/132397.