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Introduction Aluminium and its alloys are the most widely used nonferrous metals for a number of applications in automotive, aerospace and construction industries, where they are required due to properties such as an excellent oxidation resistance, workability, a very low density and high thermal and electrical conductivity [1].
In this case, the absence of sufficient number of nucleation sites within the melt enabled the formation of an ultrafine eutectic that was driven by the mechanism of homogeneous nucleation.
Substrate microstructure contained elongated grains typical for cold-rolled aluminium sheets.
By comparing the two systems, some tendencies were observed: (i) lamellae eutectic has a tendency to dissolute into fibrous eutectic, (ii) this fibrous eutectic are sensitive to crystallography orientations in aluminium matrix (see the grain boundary at Fig. 3b), and, (iii) they have a tendency to further decompose into a finer form.

It can be seen from Figure (b) that when the strain reached 0.15, the sample entered the yield plateau region, and it can be seen in Figure (c) that some holes was bent and deformed, collapsed, but not completely closed.With the continuous increase of the strain,it can be seen by combining with Figure 4(d) diagram that part of the holes was completely collapsed,and the hole walls were folded, with the instant density of the porous copper alloy rising. thus the stress-strain curve exhibited a faster rise, which gradually transited to the densification stage.When the strain finally reached 0.50, in addition to a small number of holes were not completely closed and other holes were completely collapsed and folded.
The pores became smaller after creep, and the porosity was reduced.A number of holes had cracks, but there were no significant changes in the alloy phase, grains and grain boundaries.Throughout the creep process, the porous copper alloy mainly showed in the reduction of the porosity, plastic deformation of pore walls and fracture.

In order to predict the distribution of residual stresses within functionally graded coatings, a general solution is obtained based on the classical beam bending theory [13], the advantage of this model is that the solution of residual stresses is independent of the number of layers in coatings.
base metal weld HAZ Fig. 2 Double ellipsoid model of heat source[20] Fig. 3 Computation result and macrograph of real sample Results and Discussion The substrate grain size could influence the adherence of enamel/metal.
The internal stress of the coating/metal system, which may cause the coating failure, could produce during fast cooling with uneven grain size [2].
Having coarse grain, high tensile stress (see fig.7) and pores appearing at the interface (Fig.4a and Fig.4b), the overheated zone was a dangerous zone.
In imperfect normalized zone, because the structure transformation did not carried out thoroughly, the microstructure was the mixture of coarse ferrite and fine pearlite and ferrite that couldn’t meet the request to the grain size and micro-cracks, which were shown in figure 4d by white arrows, appeared at the metal/coating interface, so there became one of the dangerous zones.

Aggregative Stability of Dispersed CNTs Suspensions Indicator name Cylinder No. 1 2 3 4 5 6 7 8 9 10 11 12 Concentration of plasticizer, g/l 0.1 0.2 0.4 0.6 0.8 1.0 1.5 2.0 2.5 3.0 4.0 5.0 Protective number of the suspension, *10-3 g/l 0.01 0.04 0.12 0.3 0.56 0.8 1.95 3.4 5.25 7.5 13.2 21 Aggregative stability of CNTs suspension, day 1 1 1 1 1 1 2 2 2 7 >7 >7 Evaluation In the course of investigations into the aggregative and sedimentative stability of water-polymer CNTs suspensions, it has been established that the plasticizer based on sulfonated naphthalene formaldehyde resins has a stabilizing effect.
Mechanism for the formation of DEL on the surface of CNTs (a) and the scheme of the structure of the micell of CNTs stabilized with sulfonaphthalene formaldehyde (b): 1 - aggregate of CNT; 2 - layer of potential-determining ions; 3 - counter ions of a dense part of a double electric layer; 4 - counter ions of the diffuse layer; 5 - CNT micell; 6 - gel-like film which consists of the radicals of the backbone chain R-SO3- When stabilized suspensions of CNTs with a lyophilized surface are added into the cement, an increase in the mobility of the cement paste is observed at the initial moment, which is due to the mutual repulsion of negatively charged particles of stabilized CNTs and hydrated cement grains (refer with: Fig. 5a).
The former ones acquired a negative charge due to the formation of an oriented layer of anionic plasticizer on the CNTs surface; the second ones - due to the flow of the process of hydrolysis on the surface of cement grains.
It has been established that when cementing with a stabilized CNTs suspension, mutual repulsion of negatively charged CNTs particles with a negatively charged surface of hydrated cement grains is initially observed.
With further hydration, the shell which consists of hydrated newgrowths is saturated with ions Са2+, charging the surface of hydrated grain positively, causing the attraction of CNTs, which leads to self-reinforcement of the hardening system. 5.

High plasticity of alloys stipulates the possibility of the creation in them by means of intensive deformation of extremely disperse grain structure and dislocation cellular substructure, which is absent in Al-Mg alloys without Sc.
A number of the disperse secondary particles increases, and they stabilize the cellular dislocation structure.
The grains of superplastic materials must be of micron or even submicron size.
Since the temperature of superplastic deformation for aluminum alloys is 400-500 oC it is necessary to prevent the grain size growth in the process of deformation.
The recrystallization temperature grows strongly, the grain size in as cast conditions decreases, both characteristics of strength and plasticity increase, workability and production ductility increase as well.

However, in the actual situation, it is not an easy task to determine the temperature of atoms in advance because the temperature of atoms is affected by a number of factors such as the current density, substrate temperature and the geometry of the slit.
When Sample A is heated, the Cu film is subjected to thermal stress because of the mismatch in thermal expansion coefficients between the metals, and the hydrostatic stress concentrations occur at the grain boundaries due to the anisotropy of the grains in the polycrystalline Cu films.
The gradient of  is the driving force for atomic diffusion and it is known that Cu atoms diffuse more easily on the surface than via grain boundaries.
The weak spots in the oxide layer form pathways through which Cu atoms can migrate externally due to the lower compressive stress that operates at the interface, and such weak spots may be located at the grain boundaries in the oxide layer.

A population of grains is chosen with a distribution of orientations and volume fractions that match the measured texture.
Each grain in the model is treated as an ellipsoidal inclusion and is attributed anisotropic elastic constants and slip mechanisms characteristic of a single crystal.
Interactions between individual grains and the surrounding medium (which has average properties), are performed using an Eshelby type self-consistent formulation.
Since the properties of the medium derive from the average response of all the grains, it is initially undetermined and must be solved by iteration.
This study also highlights the benefit of obtaining diffraction spectra containing peaks from a number of reflections.

The yield strength of the sintered PD powder was higher than that of the sintered SSS powder [5] because the dispersed particles inherent in the PD powder suppressed grain coarsening of the matrix during sintering, resulting in a smaller grain size of the matrix in the sintered PD powder than in the sintered SSS powder.
Fig.1　Schematic diagram of how to load sample powders into MA jars Experimental Procedure Al powder (purity 99.9%, average grain size 30 μm) and Y2O3 powder (purity 99.9%, average grain size 4 μm) were used as raw materials.
Fig. 2(a-d) shows that the number of Y2O3 in i-MA decreased with MA time, suggesting that Y2O3 was dissociated by MA and dissolved in the matrix or became finer, but it remained after 48 h.

For the experiments, three different grain sizes (blasting no. 1: corundum of 0.12 – 0.25 mm grain size, blasting no. 2: corundum of 0,25 – 0,5 mm grain size and blasting no. 3: corundum of 0.5 – 1.0 mm grain size) were chosen and tested for comparison with the first test series.
Statistical design of experiments was carried out both to minimise the number of tests and to recognise the potential interactions among the possible influencing factors.

The base material consists of a cold worked microstructure, whereas the heat affected zone (HAZ) region consists of elongated coarser grains and weld metal with equiaxed grain structure.
The absorbed heat promotes grain growth and results in coarser grains in the heat affected zone.
Acknowledgements The authors would like to acknowledge the support from the Ministry of Higher Education Malaysia and Research Management Centre (RMC), Universiti Malaysia Perlis (UniMAP) for awarding the research grant under Collaborative Research Grant: project number: 9023-00025 undertaking this project.