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Considering the large number of SMAs discovered, an important part is covered by Cu-based ones [11-13].
In the second schedule, the sample was loaded and unloaded up the same final strain for a defined number of cycle, then deformation was increased for other cycles.
Microstructural investigation at room temperature evidenced a typical austenitic structure, as suggested by calorimetric measurements, with large grains (average size 0.5mm), limited by the presence of the pores: in some cases smaller ligaments are constituted by a single grain.
At increased strain, a lower number of critical events were recorded, generally at higher strain than for F1.
Guilemany, Effect of cobalt addition on grain growth kinetics in Cu-Zn-Al shape memory alloy, Intermetallics 6(5), 1997, p 445-450 [6] J.

In addition to the point defects, there are defects called dislocations associated with the displacement of the atoms number in a crystal.
The lattice at the grain boundaries of the polycrystal is even more distorted.
Cement stone consists of non-hydrated grains of cement, crystalline intergrowth and tobermorite gel.
In the bulk of the cement stone there is a large number of different intergrowths of limited size, interconnected by a tobermorite gel and fine-grained hydration products of a different composition.
In addition, the presence of the mineral additives’ particles, unreacted grains of cement, pores, capillaries, discontinuities in the cement stone.

The grain size of the oxides obtained was assessed by dynamic light scattering (DelsaNanoC).
Analysis of the grain size of the samples before and after mechano-activation (Table 2) reveals that even a relatively weak mechanical treatment (22g) decreases the grain size 2-3 times.
Comparison of the grain size and the crystallite size calculated as coherent scattering domains (CSD) from the XRD-data shows that only weak deformation allows one to obtain defect-free grains, while an increase of the centrifugal acceleration leads to appearance and accumulation of defects in the grain.
The z-axis is a scan (diffractogram) number N.
The M21A10 sample features smaller grain size than М23А10 having similar CSD sizes (Table 2).

In those experiments, there were no significant stretching, bending or rotational plastic gradients, nor grain sizes or confinement effects since single crystalline samples were free-standing.
As sample dimensions become smaller, the surface-to-volume ratio and the relative number of atoms near the surface become larger.
0 1 2 3 4 5 6 7 8 9 10 11 12 13 Au from Grain B /( )YLγ σ 1 .0 7 1 s Y Y L σ γ σ σ = + 2 35 MPa 1.485 J/m Yσ γ = = (e) 0.00 0.02 0.04 0.06 0.08 0.10 0.12 0.14 0.16 0 1 2 3 4 5 6 7 8 9 10 11 12 Au from Grain C /( )YLγ σ 1 .0 6 1 s Y Y L σ γ σ σ = + 2 57 MPa 1.485 J/m Yσ γ = = (f) Fig. 1 Normalized yield stress vs. normalized pillar diameter.
From Table 1, the non-dimensional number /( )YLγ σ , which is related with the GSE on the yield stress, is of order 10-2 at the micrometer scale.
However, the non-dimensional number /( )ELγ , which is related with the GSE on elastic modulus, is of order 10-2 at the nanometer scale.

The optimal process parameters are as follows: Source material is Φ 5mm × 30mm tungsten and molybdenum wire, the number of W:Mo is 2:8, spacing is 10~15mm; Rare earth Dy using an independent plate source and evenly arranged on the Φ 100mm the barrel auxiliary cathode; the source voltage is -850~-900V, the cathode voltage is -700~-750V, the limit vacuum is 2Pa; the working pressure is argon gas, gas pressure is 30pa, the insulation temperature is 1020℃; the holding time is 4.5h.
Source material was Φ 5mm × 30mm tungsten and molybdenum wire, the number of W:Mo is 2:8, the spacing was 10~15mm, evenly arranged on the Φ100mm the barrel auxiliary cathode.
The alloying layer thickness grow little in 1050℃ compare with 1020℃, however, the sample matrix grains significantly roughened.
Figure 5 is the effect of temperature on grain size.
Fig. 4 Relationship between holding temperature and thickness of alloying layer 100μm (c) (b) (a) 100μm 100μm Fig. 5 Temperature of Permeability metal affect on the grain size (a)untreated matrix organization of 20 steel; (b)1020℃;(c)1050℃ Effect of different substrate on alloying layer thickness.

Moreover, because the pre-burying copper pipe core is equal to the chilled iron, bringing cold effect, the crystal grain of cavity wall formed by corroding pre-burying copper pipe core are tinier.
(a) position not corroded（×300） (b) cavity wall corroded（×300） Fig.2 The microstructure of cavity wall corroded and position not corroded in the castings Seen from Figure 2, the microstructure of cavity wall formed by corroding pre-burying copper pipe core is identical with position not corroded in the castings basically, moreover, its crystal grain is thinner.
At the same time, pre-burying copper pipe core contact with high temperature aluminum alloy during filling mould, which is equal in the chilled iron to bring cold effect and can accelerate solidification velocity of aluminum alloy castings, and refine crystal grain.
So the crystal grain of cavity wall formed by corroding pre-burying copper pipe core is thinner.
Moreover, because the pre-burying copper pipe core is equal to the chilled iron, bringing cold effect, the crystal grain of cavity wall formed by corroding pre-burying copper pipe core are tinier.

The results indicate that When T74 tempers are performed, the alloy can obtain a good comprehensive performance with GPII zones, η' phases and η phases as the major precipitates in the matrix and coarser and discontinuous precipitates on the grain boundaries.
And the grain boundary precipitates become coarser, discontinuous and the width of the PFZ increases obviously, which is up to 20~30 nm approximately, as shown in Fig. 1(b).
In T74 temper, the discontinuous and growing grain boundary precipitates have been suggested to reduce the susceptibility to SCC.
Loss of coherency and coarsening of precipitates as well as discontinuous and growing grain boundary precipitates will lead to an increase in conductivity.
When T74 tempers are performed, the alloy can obtain a good comprehensive performance with GPII zones, η' phases and η phases as the major precipitates in the matrix and coarser and discontinuous precipitates on the grain boundaries.

From the crater surface to the interior of the steel target, the section can be divided into 3 layers: the Martensite layer, the deformed fine grain layer and the normal matrix.
The numbers in box are Vickers microhardness values.
Moreover, the grain size of (a) is larger than that of (b), the reason is that target steel grain heated by residual penetrator grows and the heating effect of (a) is greater than that of (b).
(a) (b) (d) (c) Fig.7 Microstructure of part area in Fig.5(×1000), with enlarged view of (a) and (b) put respectively in the upper left corner of them It is shown that the section can be divided into 3 layers: the Martensite layer, the deformed fine grain layer and the normal matrix from the crater surface to the interior of the steel target by observing Fig.5 and Fig.7.
Summary By observing the change of back of target and structure around crater in this paper, it is found that oxidation of back of target is severe, reflecting an evident heat effect, and from the crater surface to the interior of the steel target, the section can be divided into 3 layers: the Martensite layer, the deformed fine grain layer and the normal matrix.

Boron is typically used as a grain refining agent.
For a large number of these 3rd generation alloys the constitution can be written as: Ti – (42 – 46) Al – (0 – 10) X –(0 – 3) Y – (0 – 1) Z – (0 – 0.5RE), (2) where, X = Cr, Mn, Nb, Ta; Y = Mo, W, Hf, Zr; Z = C, B, Si; RE: rare earth elements.
The majority of the microstructure consists of lamellar γ/α2-colonies with globular γ-grains (dark contrast) and bo-grains (bright contrast) at their boundaries and triple points (SEM- image taken in back-scattered electron contrast) [4].
The aim of primary hot-working of cast ingots is to convert (or breakdown) the coarse-grained microstructure into a fine-grained and uniform microstructure suitable for subsequent wrought processing or heat treatments.
Although the numbers on the diagram are omitted, the impact of TiAl is clearly recognizable [6].

The criteria to reconstruct the subgrains of the deformed structure were defined by setting a grain tolerance angle of 2º and defining a minimum pixel number in a subgrain.
However, if subgrains of the {111}<110>component nucleate they will display a higher average mobility because neighboring deformed matrix grains belong predominantly to the {111}<112> component.
In Fig.7b only the grains are shown of which the individual size is two times larger than the sample average..
It can be seen that the orientations of these grains are strongly dominated by the {111}<110> component which is compatible with the hypothesis of a faster growth rate of this component.
It also can be seen that the smaller grains of the microstructure are dominated by the {111}<112> component, cf.