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Table. 2 Tensile strength of specimens under different conditions Samples number Tensile strength [MPa] Yield strength [MPa] Elongation [%] Casting alloy 350 205 13 No. 1 563 450 18 No. 2 635 505 19.5 No. 3 460 375 12.5 XRD analysis.
After the cold rolling processing, we also observe that there are many nanoparticles with diameters in the range from 2 to 20nm in the matrix, the dispersal nanoparticles can pin the sub-grain and dislocation, the yield behavior of the alloy is determined by the configuration of dislocation in the copper matrix and its interaction with the dispersal nanoparticles.
In the melt solidification process, a possible reason is that iron nanoparticles may act as nucleating centers during the solidification of the copper matrix, then lowers down the critical nucleation energy, raises the diffusion activation energy and nucleation rate, resulting in a decreased dimension of the grains of the copper matrix.
It is noted that the energy system of Cu-Sn-Zn-Fe-Co alloy with plastic deformation is in the high-energy state, when taken ageing at 673Κ for 4h, the tin element diffuses into the copper matrix through the high diffusion rate passageway (such as the high density dislocation, grain boundaries, phase interface).Hence the segregation of tin element in the copper matrix and the existence of hard and brittle phase eliminate, the disappearance of these benefits to improve the strength of the alloy.

The interpretation of the Me-atom self-diffusion is difficult because of the unknown grain boundary contribution to the total diffusivity and rather high temperatures.
We define the formation energies of single point defects as: (3) (4) where is the formation energy for the carbides (-1.79 eV/f.u. for TiC and –1.77 eV/f.u. for ZrC), N is the number of MeC formula units per supercell, and REF denotes the reference state of pure Me (hcp) or C (diamond structure).
This contradiction may indicate that in one of the experiments reported in [4] the contribution from grain-boundary diffusion was higher than in the other.
Grain-boundary contribution usually results in a higher value and a lower activation energy value.

Procedure for microsections preparation consisted of grinding on the SiC abrasive papers with grades 120÷2400 and polishing on the diamond suspensions with mean grain size 6 μm, 3 μm and 1 μm.
Final polishing step was done using Struers Op-U colloidal silica suspension with mean grain size 0.05 μm.
After Na addition, the number of shrinkage pores increased (mean shape factor of the pore flat section = 0.752).
Adamiec, Methodology of quantitative evaluation of porosity, dendrite arm spacing and grain size in directionally solidified blades made of CMSX-6 nickel alloy, Mater.

Sample Annealing temperature FWHM Lattice parameter (A) Grain size D(nm) Dislocation densi4y (δ) × 1014 (lines/m2) 1 4000C 0.7804 a= 4.170 11.25 79 2 4500C 0.7628 a=4.170 11.51 75 3 5000C 0.7073 a=4.805 12.38. 65 Grain size was calculated the following equation.
The grains can be found in a variety of patterns with approximately the same proportions.
The films transmission and absorption are affected by the number and speed of dipping and annealing temperatures.

The result is a growing number of components produced from different titanium and aluminum alloys for aerospace applications in particular, in addition to a greater interest to utilize the technique in automotive and medical applications.
� Simple constitutive equation (Eqn. 3), which does not account for many features associated with superplastic deformation, like strain hardening, anisotropy, grain growth and cavitation [4, 9-11, 13]
Microstructure is accounted for by the grain size (d) and cavitation by correcting the stress value to account for the area fraction of voids.
The model accounts for microstructural evolution (grain growth and cavitation), strain hardening and variable strain rate sensitivity index m.

The resultant overpressurization can create large-scale travelling pressure waves that cause propellant grain fracture and projectile impact loads because of motion and redistribution of propellant bed, even catastrophic failures under high loading density propellant charge conditions [9].
A number of previous studies had conducted to investigate the ignition and flame spreading process associated with anomalous behaviour [9-11].
The igniter chamber where a small quantity of ball powder was burned was sealed by a diaphragm and a multiple nozzle plate from the flow chamber which contains the sample granular propellant grains.
(3) where, kp is permeability of the packed pseupropellant bed, dp is average diameter of the packed pseupropellant grains, u is fluid velocity of flow in the direction of pressure gradient, Lp is the experience coefficient from experiments.

In addition, it is very well suited for the SLM process that the maraging steel achieves its mechanical properties by a martensitic matrix that contains a high number density of nanometer-sized intermetallic precipitates, so it need to be quenched rapidly from the austenitic region to temperatures below the martensite start temperature.
An epitaxial growth of extremely fine cellular grains or dendrites across the hatchoverlap regions is observed.
These austenite grains are observed to nucleate on laths and parent austenite grain boundaries.

The cuticle layer represents the outermost surface and it consists of a number of proteins.
The average grain size is 2-3 μm.
SEM investigations confirm that the average grain size is decreased from micrometers to 100 – 200 nm.
The average size of globular grains is ~ 200 nm and the nanograins is ~ 70 nm.

The absence of reflections from aluminum on a diffraction pattern suggests that the aluminum film grew fine-grained (Fig. 4а).
It must be noted that in a number of works the crystal structure of the Ni2Al3 phase is considered as the B2 NiAl phase with the ordered arrangement of constitutional defects on the B2 underlying the lattice [19]. 25 35 45 55 65 75 85 2Θ (deg.)
Microstructure of multilayer and heterogeneous alloys consists of grains with different composition.
At temperatures of the phase transformations the intensive processes of intermixing, structural reconstruction, and phase formation occur at grain interfaces.

The desired final grain size in the product is 35mm.
The optimum ram velocity for achieving the above grain size is found to be 160mm/s when billet temperature is 1080oC.
The measured average grain size was 38mm, very close to the designed value.
This is a first of its kind dual purpose system in the country and has been applied for a number of applications.
Acknowledgements This paper is written based on the innovative ideas and consistent efforts of a large number of dedicated scientists at IGCAR, mostly from the Metallurgy and Materials Group.