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The MZ 1 specimen composed of YSZ 1 powder is characterized by the TC defect structure with large numbers of micropores and microcracks, while MZ 2 specimen with YSZ 2 powder contains only a few microdefects and is fairly densified as compared with the other TBC systems.
the same TC powder as MZ 2, on the contrary, a number of the macrocracks have already extended or penetrated through major part of the TC over the length of 100µm vertical to the TC / BC interface.
The 240~400 numbers of microphotographs per one specimen were taken until completing the test.
It was confirmed that the initiation site of TC spalling should coincide with the region subjected to the more extensive plastic deformation in the alloy substrate for all the specimens tested, of which magnitude is probably different depending on the crystallographic orientation for each grain.
Such a deformation might depend strongly on the relative crystallographic orientation to the loading axis of individual grains with relatively large size in the alloy substrate.

According to a dispersion relationship of the helicon wave, the electron density is proportional to magnetic field if the parallel wave number is fixed.
The Hiden probe measures the electron and ion currents to provide electron and ion number density measurements [18].
The probe has an error of ±50% for electron and ion number densities and ±20%for electron temperature [19].
Fig. 5(a) shows there are a large number of small dots adsorbed on the surface of big grain.
Compared to Fig.5 (a), the average grain size decreases with the increasing RF power.

The basic value is the number of AE events per a period of time.
This parameter is a simple indicator for determining the degree of damage to a material, where generally applies that a larger number of AE events indicates a higher degree of material damage.
Fig. 2 The number of AE events during the static modulus of elasticity test, the vertical axis shows logarithmic scale.
Kalina, Effect of the by-pass cement-kiln dust and fluidized-bed-combustion fly ash on the properties of fine-grained alkali-activated slag-based composites, Mater.
Karel, Shrinkage of Fine-Grained Composites Based on Alkali- Activated Slag, Non-traditional Cement & Concrete, Brno, 2017, 20-21

No difference in grain structures among the three different planes was observed.
The average grain size was about 20μm.
It should be noticed that the basal planes, on which slip is easy to occur, for the 45-degree and transverse specimens are oriented at 45゜and normal to the loading direction. 103 104 105 106 107 108 40 60 80 100 120 140 Number of cycles to failure, N f (cycles) Stress amplitude, σa (MPa) Longitudinal Transverse 45-degree Longitudinal Transverse 45-degree Interrupted tests Table 2 Tensile properties of AZ61.
The relationship between the crack length and number of cycles normalized by the fatigue life is shown in Fig. 7.
Therefore, it is suggested that the longitudinal specimen has less number of slip systems and consequently indicates higher fatigue limit compared to the 45-degree and transverse specimens.

Since the coarse (larger than 1 µm) IM particles provide sites for crack initiation, the lower toughness and resistance to propagation of fatigue cracks are related to their size and larger number in the matrix.
Because the limits to reduction of these impurities are set of cost, many commercially available 7xxx alloys contain significant amounts of Fe and Si, which react with Al and alloying elements to form a large number of IM phases [1,2].
The plots of crack length, a, vs. number of cycles, N, were made and average crack growth rates, da/dN, were computed.
The EDS analysis in TEM confirmed that both small precipitates in the former dendrite interiors of the cast structure and relatively coarse precipitates at the grain boundaries were those of the η-MgZn2 phase, Fig. 1c.
A general view of the fractured specimen surface illustrated in Fig. 3 shows that in the other alloys microcracks are initiated more readily than in the alloy 1 because of the higher number of larger particles.

In this paper, the isothermal solidification dendrite growth model coupling the forced flow-field for binary alloy was established, calculating the phase field and solute field equations by the finite difference method; the flow field equations were calculated by Sola algorithm; in order to save calculation time, reduce the computational volume, double grid method was adapted to calculate the phase field, solute field equations and flow field equations, respectively; take Al-Cu binary alloy for example, the simulation results can capture the interactions of the liquid metal flow and multiple grains dendrite growth under forced convection environment.
In this article, the binary alloy multi-grains dendrite growth isothermal phase-field model which Feng Li et al [12] proposed was coupled with the flow field, the phase-field equation can be expressed as equation (1): (1) Where, M is solid interface migration rate, Φ is phase field order parameter, t is time variable, ε(θi) is a parameter associated with the interfacial energy, fΦ represents the first derivative of free energy density on the phase-field order parameter, and its representation form is as equation (2): (2) Where, R is gas constant, T is temperature, Vm is molar volume, h(Φ) is potential function, W is phase field parameter, g(Φ) is residual free energy function, c represents the concentration of solute in the alloy, the subscript L, S represents for liquid and solid phase respectively, the superscript e represents equilibrium state.
Correspond to the x and y axis (the horizontal direction is x) in coordinate system, the computational grid number of phase field and solute field both are 1200×1200, the grid size is 1 × 10-8m (Δx = 1 × 10-8m ), set the initial nucleus as the ball with the grids number radius R=10.
Because of different thickness of the grids, resulting in different space and time accuracy of flow field, phase field and solute field numerical solutions within the calculation region, for this reason, space factor Nw and time factor Nt were introduced, ， (10) (11) (12) (13) (14) (15) Where, V represents the flow velocity, the subscript f indicates the numerical solution of the calculated flow field grid, I, J, T and i, j, t represents the space and time node in different grids, respectively, in formula (12), (13), n is a natural number less than Nw, in formula (15), n is a natural number less than Nt.

According to the degree of influence of additives used to reduce ice formation in the slag in concretes, containing cements can be ranker number: SX (5%) + SP (0.6%) > NC (5%) + SP (0.6%) > SP (0.6%).
In such cements clinker particles are first hydrate to form a hydrosilicate gel the coating grains of slag and clinker.
Because highly basic silicate forming a shell around the grains of slag and lime is dissolve at, the site of primary hydrate, film is amorphized, enriched with alumina and silica.
According to the degree of influence of additives used to reduce ice formation in the slag in concretes, containing cements can be ranker number: SX (5%) + SP (0.6%) > NC (5%) + SP (0.6%) > SP (0.6%).

Meanwhile, TEM and STEM images showed that a large number of secondary phases appeared after the homogenization, which were mainly distributed in the inter-dendrite area.
The primary phase of Al-Zn-Mg-Cu alloy were Al2Mg3Zn3 and Al2CuMg distributed in the grain boundaries, and the primary phase of Al-Zn-Mg alloy was block-shaped Al2Mg3Zn3[3-5].
A large number of secondary phases precipitates during the homogenization
Evolution of Grain Boundary Phases during the Homogenization of AA7020 Aluminum Alloy.

Strain gauges allow recording strains at a limited number of discrete points and do not provide sufficient amount of data, thus increasing the cost of the analysis.
Such approach has a number of disadvantages – the strain must be within a certain range, the deformation is averaged over the strain-gauge length, the measurement is limited to the strain-gauge location and the surface of the loaded element must be smooth enough to attach the gauge.
For that purpose a mortar composed of lime and Portland cement in ratio 7 : 3, and common river sand of grain size 0-2 mm in binder to aggregate mass ratio 1 : 3 was prepared.

Both of these proceses produced inperfect protective layers, but we proved that a PLD DLC film over the diamond layer does reduce the number of pinholes in the coating.
The DLC grains cluster around the pinholes and forms hills over them.