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Among the advantages of this technique as compared to other tools such as transmission electron microscopy, is the fact that accurate, quantitative numbers can be provided for the characteristics of the precipitate size distributions, measured on a very large number of particles.
Al3Zr precipitates are used as anti-recrystallisation agents due to their ability to pin grain and subgrain boundaries.
Since Zr and Sc atoms have very different atomic numbers, it can be expected that the chemical inhomogeneity inside the precipitates results in a specific small-angle X-ray scattering signal.
Once these parameters are known for a given metallurgical state, the average precipitate composition is known and the precipitate volume fraction fv can be calculated from the integrated intensity Qo : ()2mp 2 o v 2 Q f ρ−ρπ ≅ , where ρp and ρm are the electron densities of the precipitate and matrix and ()∫ ∞ = 0 2 o dqqqIQ is calculated from the experimental data. 0 50 100 150 200012345678 5°C/min 10°C/min 430°C/min Time (h) Precipitate radius (Å) 0 100 1 10 -3 2 10 -3 012345678 5°C/min 10°C/min 430°C/min Time (h) Precipitate volume fraction 0 20 40 60 80 100 012345678 Time (h) Zr/(Zr+Sc) in the shell (%) 5°C/min 10°C/min 430°C/min 10 100 1000 10000012345678 5°C/min 10°C/min 430°C/min Time (h) Precipitate number density (µm-3 ) Figure 5: Precipitation kinetics at 450°C of the AlZrSc alloy, as a function of the heating rate: (a) precipitate size, (b) precipitate volume fraction, (c) composition of the
These features of fast nucleation and slow growth and coarsening enable to obtain a remarkably stable microstructure of fine Al3(Zr,Sc) dispersoids, which have proven to be very effective in controlling the grain size of many Aluminium alloys.

In terms of nucleation and growth, when a layer is cooled to 700°C, a large number of fine β-particles nucleate.
This results in a smaller amount of growth of the columnar structure, that results in smaller columnar grains at the top layer.
The martensitic decomposition is a classic “nucleation and growth” process, and when a layer is cooled to 700°C, a large number of very fine β-particles nucleate.
The regions close to the upper edge are the last to be printed and hence are subjected to a lower number of reheating/cooling cycles.
The less repeated heating results in a lower amount of growth of the columnar structure, and subsequently smaller columnar grains on the top layers are obtained.

It is known that when mechanical strain exceeds the irreversible strain, cracks will form at high-angle grain boundaries and cause the degradation of critical current [12].
The samples were numbered 1#, 2#, and 3# respectively.
Parameters of the samples used in monotonic tensile experiment Sample number 1# 2# 3# Critical current Ic0 (A) 158.96 156.43 152.34 Strain 0.485% 0.458% 0.439% Normalized critical current 96% 96% 93% Fig. 2 Normalized critical currents and stress versus strain relation in copper reinforced Bi-2223/Ag (77K, self-field) Fig. 3 Stress-strain curve in copper at room temperature Critical currents versus repetitive tensile stress relation.
The samples were numbered F1, F2, F3, and F4 respectively.
Effect of tensile strain on grain connectivity and flux pinning in Bi2Sr2Ca2Cu3Ox tapes.

For the oxidation of metal M in H2O giving MaOb, the global oxidation reaction can be written as follows: (5.3) Let is the differential of the number of mole of water vapour that enters the reactor, is the differential of the number of mole of water vapour consumed by oxidation and is the differential of the number of mole of hydrogen molecule produced as a result of the oxidation.
From Reaction 5.3, we see that the number of mole of H2O consumed equals the number of mole of O used to form the oxide which is the one obtained from the experiment, thus giving (5.6) where is the differential of the number of mole measured from the thermogravimetric experiment.
From Reaction 5.3, we can also see that the number of mole of H2O consumed equals the number of mole of H2 gas produced by the oxidation reaction.
In that case, the -Fe2O3/(Cr,Fe)2O3 with the thickness higher than 5 mm was found at the heart of the alloy grain while the -(Cr,Fe)2O3 close to the steel grain boundaries remained partially protective.
It can increase the oxygen permeability in the ferrite matrix or refine the oxide grain boundaries.

Each crystalline was then marked and the total number of crystals was counted using software.
The density of the crystals i.e. the average number of crystals per square micron was then calculated.
Variations in size and number of crystals are presented in Fig. 4.
From which we can see clearly: (1) when the Ua is less than 220V, the crystal size decreases rapidly with the increase of Ua and when the Ua is over 220V, the size of crystals increases slightly with the increase of Ua; and (2) with the increase of Ua, the crystal number increases rapidly when the Ua is less than 220V and the number decreases when the Ua is over 220V.
It is speculated that the melt-quenched titania crystallizes into grains and converts to anatase, and subsequently to rutile by virtue of local high temperature–pressure sintering in the proceeding microarc discharging.

Table 1 The formula of ABS (wt%) inorganic particle 0% 5% 10% 15% 20% number 0 1-1 2-1 3-1 4-1 ABS: Al2O3 100:0 100:5 100:10 100:15 100:20 number 1-2 2-2 3-2 4-2 ABS: Talcum powder 100:5 100:10 100:15 100:20 number 1-3 2-3 3-3 4-4 ABS: Kaolin 100:5 100:10 100:15 100:20 number 1-4 2-4 3-4 4-5 ABS: CaCO3 100:5 100:10 100:15 100:20 The modified ABS materials were made into 3D printing silk according single screw extruder after drying in drying oven in 80℃ for 4h.
That would increase the number of material defects and damage the compactness of the matrix and decrease the strength.
The load will directly concentrate on the inorganic particles and caused small silver grains (cracks) When the added inorganic particles are larger than the diameter of the matrix resin, which resulting in the increase of brittleness of the material and the decrease of toughness.
Round and smooth AL2O3 particles occupied a large number of dimple centers.

The commonly used metals are polycrystalline, because each grain orientation is different, apart from this, the microscopic and macroscopic defects such as the dislocation, mixing and second phase exist, there is anisotropy and heterogeneity in polycrystalline.
And the fatigue damage degree of base is proportional to the number of stress cycle.
We assume the number of stress cycle which is reached when the base is damaged under a certain level stress is.
The number of stress cycle is.
(2) As Eq.2 shows, is the number of stress cycle, is the number of stress cycle when the base is damaged.

Effects of the number of layers and layer interval.
Figure 4 represents the stress-strain curves for various layer numbers.
Since the total number of the layers is 24 and the layered material is 12, the material ratio is 0.5.
Stress-strain curves for various layer numbers keeping the cross-sectional ratio constant.
Ohno: Molecular dynamics simulation of shape memory behaviour using a multi-grain model, Modell.

In general, a number of factors influence the abrasion process.
These factors include mean velocity of sands, mass of the sand, concentration of the sands in a liquid flow, grain size and shape of the sands and angle of attack at which the sands collide with the surface etc [1].
The governing equations are described below[4] Continuity equation of liquid： (1) Momentum equations of liquid (2) Where represents the Coriolis force.is total pressure, is static pressure, is the volume density of the particle phase, is the number of particles per unit volume, is the particle mass and is the drag coefficient of unsteady flow.
Fig. 1 Francis turbine runner Table 1 Parameter of prototype Francis turbine Diameter of runner(cm) 175 Number of main blades 15 Number of splitter blades 15 Number of stay vane 24 Number of guide vane 24 Rated head (m) 231 Rated power (kw) 25000 Rotational speed (rpm) 600 Rated flow rate (m3/s) 13.1 Analysis of numerical calculation results Figures 2(a) is the streamline distribution in the runner.

For the 1Cr18Ni9Ti sample: from the perspective of impact frequency, the deformation rate of the gridding in every layer is largest in initial thousands of times, with the increasing number of impact, deformation rate decrease gradually, until zero; View from the layer in coordinates, more closer to the surface gridding layer, the deformation rate is larger, The average deformation rate of the gridding decreases continuously with the increasing layers deep.
After a certain number of repeated impact, the metallographic structure of Ni-2 laser cladding coating component was observed by TEM after cutting, brigandine sample, grinding, polishing and aqua ragia corrosion, which was shown in Fig.5.
The broken grain is the performance of deformation. 20 20 Before repeated impact After repeated impact Fig.5 Metallographic organization chart of Ni-2 laser coating before and after repeated impact Conclusions (1) There is obvious difference between the two repeated impact tests of 1Cr18Ni9Ti sample and 1Cr18Ni9Ti sample with Ni-2 laser cladding coating.