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Since there is a proportional relationship between the number of blasting operations and the machining groove depth, the groove depth may also be adjusted by changing the number of blasting operations.
We used a set number of 100 blasting operations (number of nozzle scans) in this experiment.
Fig. 6 Effects of blasting distance and blasting pressure on machining ratio Fig. 7 Effects of scanning speed on machining ratio and groove depth Table 2 Micro blasting conditions Blast machine HOZAN, SG-106 Blasting nozzle (Ceramics) Hole diameter: 2mm Abrasive grain WA #800 Blasting pressure 0.5 MPa Blasting distance (Gap between nozzle and glass) 75 mm Scanning speed 15 mm/s Blasting quantity of abrasive grain 50 g/min Workpiece Glass Micro blasting of micro channels.
The solution we considered was to blast abrasive grains diagonally at the workpiece to form a U shaped groove (Fig. 9).

It can be seen from Fig.1 a large number of hard metal cutting tools can be coated simultaneously at the same time.
This is further demonstrated in Fig.4, where a number of diamond film coated YG6 cutting tools are presented, ranging from lathe cutters and millers, drills and end mills.
It must be noted that grain size of the diamond films shown in Fig.3 was about 1-2 microns, and is usually regarded as microcrystalline diamond coatings.
In the present investigation nano-microcrystalline composite diamond film coatings were also developed which has a average grain size less than 200nm [9].
The authors wish to thank the NSFC (National Science Foundation of China) for the financial support under contract number of 50872010.

Samples failure was caused by exceeding the timber strength in tension perpendicular to the grain.
For decreasing the probability of the crack occurrence during sample testing, reinforcement should be in the direction perpendicular to the grain [6].
Screws were oriented perpendicular to the grain.
As the number of samples is small, the presented results are prone to statistical error.
Aknowledgement This paper has been achieved with the financial support of the Ministry of Education, Youth and Sports of the Czech Republic – funds of conceptual development of science, research and innovation assigned to VŠB-TU Ostrava in 2013 under identification numbers SPP IP2213313, SPP IP2213314 and by the Student Research Grant Competition of the Technical University of Ostrava under identification number SP2013/104.

Microstructures of these alloys are similar and comprise aluminium grains in a matrix of Al-Si eutectic (e.g.
During age hardening, the grains of aluminium within the matrix material are strengthened by the formation of dense dispersions of precipitate phases such as θ' (Al2Cu) (Figure 1 (b)), β" (Al3(MgSi) [6], σ (Al5Cu6Mg2), and L/Q' (Al5Cu2Mg8Si6) , as well as a number of pre-cursor phases.
(a) shows the ααααaluminum grains bounded by the silicon phase and (b) finely dispersed θθθθ'''' precipitates within the αααα-aluminum grains in an [001]αααα orientation.
Towards the centre of a component, the Al grain size is larger and the Si plates are present in fewer numbers and larger sizes.
The silicon particles fragment and spheroidize, then undergo Ostwald ripening, decreasing in number.

Results and Disscusion Starting powder mixtures consisted of a-Si3N4, Al2O3, Y2O3 grains and 3 wt% of CNTs as addition to batches.
In all case, the average size of Si3N4 grains is ~ 500 nm.
At shorter holding times (3 and 5 min) 200 nm average grains size is characteristic (Fig. 2a,b).
At longer holding times (10 min) grain coarsening are revealed, silicon nitride grains with 500 nm can be observed by SEM (Fig. 2c).
In all cases, the average size of Si3N4 grains is ~ 300 nm – 500 nm.

In the HAZ of the sample equiaxed grains are visible at each side, but in the HAZ of duplex steel grain size is higher than 100 µm, and the ferrite content is significantly increased.
In the HAZ of the 2404 type duplex steel equiaxed grains can be seen.
There are acicular austenite at the boundary of large ferrite grains.
In the weld metal thin austenitic grain boundaries and thin Widmanstätten-like austenite within the ferrite grains present as shown in Fig. 1. j, k, l.
In the root of the 2404, a good performance appeared after 72 hour (Fig. 2. b).On the face of 2304 a hole appeared a hole in the HAZ (Fig. 2 c), although in the root number of pits was higher in the HAZ (Fig. 2. d).

The method provides us shorter slurry making time and finer microstructure of α grain with around 50 μm in its size.
EBSP images were also used to count the number of particles so as not to count the same grain with overlapping.
Figure 7 shows the number of primary particles and corresponding EBSP images.
In the case without vibration (a) and (b), the number of primary particles was low at the same level, and coarse dendritic structure was observed from the EBSP image (b).
In the case of vibration only while pouring (c), the number of primary particles in the center part of the slurry significantly increased.

One of the examples of extrinsic factor is grain boundaries which act as regions of enhanced scattering for conduction process as the boundaries of the grains consist of more magnetic disorders compared to the core [4].
By inspection on the SEM images, it can be concluded that Nickel substitution decreases the grain size.
Based on the SEM image in Fig. 1, it can be seen that nickel substitution decreases the grain size of the sample.
This will increase the number of grain boundaries thus, strengthen the scattering of the carriers resulting in an increase in the overall resistivity [13-15].
Acknowledgment Universitas Indonesia financially supported this work under research grant “Hibah PITTA 2018” with grant contract number 2241/UN2.R3.1/HKP.05.00/2018.

Presented model considers the microstructural ingredients that are immobile dislocation density, effective grain size and dislocation cell size as the variables to address the creep.
An increase in the number of immobile dislocations is a key indicator of strain hardening in low stacking fault energy materials (LSFE).
The overall/total flow stress can be obtained as the sum of different strength contributions, i.e., from dislocations, Grains and cells, and solid solutions.
Furthermore, by incorporating the twin boundary concept [15], the grain boundary strengthening contribution is calculated using the modified Hall-Petch contribution and is represented as [10], σHP=KHPGsmTgeffGRT=KHP GsmTgGRT1+2Ktlngg012
Moiz, PhD thesis, The influence of grain size on mechanical properties of Inconel 718, 2013.

It revealed, that especially the grain refinement by multiple recrystallization and final transformation kinetics needs to be modeled in a very detailed manner.
Finally, the amount of microstructural constituents, the ferrite grain size, the interlamellar spacing of pearlite and the mechanical properties are evaluated.
As a result, the development of rod surface and core temperature and austenite grain size of steel grade 50CrV4 is shown in Figure 4.
Based on a huge number of Gleeble experiments and industrial trials, the final microstructure and mechanical properties can be predicted with a sufficient accuracy, so that in many cases the effort for destructive materials testing can be reduced.
The resulting finer grain size after TM-rolling also gives a higher ductility or forming limit at similar strength levels.