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Dissimilar aluminium alloy materials were successfully friction stir welded with very good joint efficiencies by number of researchers.
Their results indicated that the recrystallized grains in the weld nugget zone (WNZ) of the joints exhibited the largest size in the middle part and the smallest size in the lower part.
Sato et al. [6] reported the formation of basin-shaped nugget on friction stir welding of AA6063-T5 plate and Mahoney et al. [7] reported elliptical nugget zone in the weld of AA7075-T651 and the metallographic studies showed that the grain size in the stir zone is much finer than that in the base metals [8].

The pearlite is surrounded by ferrite, predominantly at the prior austenite grain boundaries.
Graphitic nodules number decreased in this area as well.
Results of hardness profile measurement using Vickers method with indentation force 0.98 N (HV0.1) are compared in Fig. 5 EN GJL-200 EN GJS-700 CuNi Fig. 5 Hardness profiles of evaluated cast irons after laser surface hardening The hardness measurement was realized in a defined matrix, which does not eliminate the positioning of indenter in soft structural areas (like graphite particles or ferrite grains).

AFM results show the grain size and roughness increase from PZT to PSZT, PSZT-PZT and PZT-PSZT.
The grain size distribution and the average roughness have strong correlation to the observed ferroelectric properties as well as to the derived mathematical relation between Pr vs Vc, but further work must be done to construct a theoretical framework explaining the behaviour in terms of exact structure and surface interaction between layers. 4.
Future research can be done to focus on increasing the number of layers of PZT or PSZT from the current 4 to 6, which is often the maximum thickness of these thin films before cracking occurs.

The difference in grain size observed between outer and intermediate zones must be due the solidification rate in centrifugal casting: the liquid metal comes into contact with the cold mould walls and as a result solid nuclei form, creating a chilled region.
This could be due to the increase in the apparent viscosity of the semisolid slurry caused by the larger number of particles (self-induced viscous drag) [16], which limits the slurry's ability to discharge trapped gases.
Conclusions The results in this work show that the centrifugal casting conditions induced variations of grain size between the outer and inner peripheries of Al / SiO2-Al2O3 5 and 10 vol% SFGMMC.

However, a large number of researches and practical work show that in some key sections of the highway, such as connecting section between bridges and tunnels, highway emergency parking area, overpasses and the protection area of construction; a reasonable set of road lighting system can effectively enhance the driver's vision at night and improve driving environment conditions, thereby significantly reducing the incidence of fatal accidents at night.
Networked distributed control system realizes networked real-time monitoring and centralized management of the luminaries, and grain size control has achieved the degree of single lamp control.
Networked distributed control system realizes networked real-time monitoring and centralized management of the luminaries, and grain size control has achieved the degree of single lamp control.

Boron makes grain refinement easier, and the formation of borides improves the mechanical properties of the surface coating being formed
Brazilite containing zirconium oxide (ZrO2) makes the grain refinement easier.
Analysis of mineral basis established that the Far Eastern region has considerable deposits of mineral raw materials including waste products of mining industry that contain a sufficient number of elements (tungsten, boron, titanium, zirconium, etc.) for manufacturing welding surface materials. 2.

Table 1 Ratio of raw materials and sintering schedule of the samples Number Molar ratio of Al/B2O3/C Temperature (°C) A1 8:2:13 1750 A2 8:2:13 1800 A3 8:2:13 1850 A4 8:2:13 1900 A5 8:2:13 1950 B1 8:2.5:13 1800 B2 8:3:13 1800 B3 8:3.5:13 1800 Phase identification of each product was examined by powder X-ray diffractometer (X’Pert Pro MPD) with a monochromatic Cu Kα (λ=1.5406 Å) radiation source.
The different morphology Al8B4C7 grains were synthesized.
At 1800 °C, Al8B4C7 grains were hexagon plate-like with thickness of 5-10 μm and size of about 100 μm.

The process of measurement was the following: 1g delay composition pressed into metal shell was prepared into grain with a diameter of 40 mm and a length of 38 mm.
The grain placed on equipment of flaming velocity measurement.
The formulas used were (1) (2) (3) In these formulae: rA is the average burning rate (mm/s), ri is the burning rate of i sample (mm/s), n is the number of testing samples, α is the delay precision (%), β is the temperature coefficient (K-1), rminvalue + 70° is the minimum of burning rate at 70° (mm/s), rmaxvalue 50° is the maximum of burning rate at 50°(mm/s), and the testing temperatures were Thigh=343 K, Tlow =223 K.

Zn [% mass] Al [% mass] Cu [% mass] Zn [% mass] ZA8 90.6 8.4 1.0 90.6 ZA12 88.2 11.0 0.8 88.2 ZA22 75.3 22.1 2.6 75.3 ZA27 71.2 26.5 2.3 71.2 The Zn-Al-Cu type alloys are characterized by a number of advantageous properties comprising low fusion temperature, good castability, high strength and hardness, good fatigue strength, low density, low friction factor, low wear rate speed, and low production cost.
ZA12 and ZA27 alloys have a dendritic structure, the grain size and the size of the interdendritic area being depended on casting parameters.
Cooling rate has strong influence on the grain.

Moreover, phase transition is also governed by grain boundary concentration, which can be expected to be increased with greater surface area materials.
When the specific surface area increasing, the grain boundary concentration would increases, and these considered to be the anatase nucleation sites for TiO2 powders [12].
A large number of nanotube structures with uniform diameters around 10 nm can be observed.