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Introduction Magnesium-based alloys have a number of advantageous physical and mechanical properties, which make them an attractive choice for many industrial applications.
Fine grains are present in the microstructure.
In contrast, the samples tested at 696 K show a coarse a duplex microstructure with fine and large grains.
Therefore, it will be convenient to cool rapidly the alloy after forming in order to avoid grain growth.
Summary and Conclusions 1) The optimal forming temperature of the ZK30 alloy is 641 K (368ºC) at 8.7 s-1. 2) According to the stress exponent found, the mechanism controlling deformation in the alloy is slip creep. 3) A rapid cooling is convenient after testing to avoid grain growth.

Table.1 The chemical compositions of the cutting ammunition (wt %) CuO Fe2O3 Al Ni KNO3 Al2O3 Others 7 23.4 51.6 4.7 7.8 1.5 4 Table.2 Length of cartridge (mm) serial number 1 2 3 4 5 Length 50 70 90 100 120 Table.3 The chemical compositions of Q235 (wt %)[2] Trademark Level C Si Mn S P Cr Q235 A 0.14～0.22 ≤0.30 0.30～0.65 ≤0.050 ≤0.045 ≤0.030 Results and discussion Test results as below: Figure.1 Relationship between length of cutting cartridge and injection time Influence diagram of changing length of cutting ammunition influencing on macroeconomic effect of punching: Figure.2 Relationship between length of cutting cartridge and cutting quality Macrograph of the hole as follows: a) 90mm b) 120mm c) 50mm Figure.3 Different length of cutting cartridge to macrograph of punching As the figure 1 show that if the length of cutting ammunition increase, ammunition content increases and combustion time is markedly longer, directly
In the combustion chamber, the mass flow rate is as follows: (1) Wherein: —The density of the combustion products either interface —The burning rate of cutting agent A—The combustion surface between the bottom of the grains to the calculate section the burning rate and heat transfer combined heat transfer coefficient formula of that: (2) (3) Wherein : —perimeter of the channels; , —stagnation temperature of burning gas So we can get that different lengths of the cartridge directly affect inside pressure of the combustion cutting ammunition.
Assuming the burning rate of pharmacy grains unchanged and approximate no erosion burning, proportional to the relation between convective heat transfer coefficient and combustion area of 0.8 powers.
Put the formula of to the above equation At the X-section we can get.Convective heat transfer coefficients gradual increase along the length direction of the grain and a maximum at the end of the charge[3].
Jet times gradually reduced with little mass of grains while the length of cartridge is gradually shortened in 90mm rang.

b a Fig. 1 Macro-morphology of the sample (a. outer surface, b. inner surface) groove groove sand Fig. 2 Local macro-morphology of tube inner surface Physical and Chemical Properties Metallographic Analysis Metallurgical structure, grain size and nonmetallic inclusions analysis were carried out according to GB/T 13298-1991, ASTM E45-2005, ASTM E112-1996 respectively.
b a Fig. 3 Cross-section macro-morphologies of specimens(a. horizontal; b. longitudinal) Table 1 Nonmetallic inclusions, metallurgical structure and grain size analysis results sample nonmetallic inclusions metallurgical structure grain size A B C D thin thick thin thick thin thick thin thick tube 1.0 0 1.0 0 0 0 1.5 1.0 tempered sorbite, ferrite, upper bainite, exist segregation 9.0 level Table 2 Crack analysis results sample analysis result tube Corrosion existed on both inside and outside of the tube surface.
The corrosion product on tube inner surface was very dense and had a large number of grooves which exhibited a certain direction.
H+ is deoxidized to H atom first at inclusions, grain boundaries, etc..

Most of these methods have a number of disadvantages, such as process duration, coatings thinness, low adhesion, necessity of high temperatures and energy intensity as a result [2].
Its basis is gray or very dark grains with geometrically irregular shapes of low-density material being in the matrix of the high-density material.
In gray areas contrast (Fig. 4c) reveals grains in light matrix more closely, and their material can prevail over the light matrix material in volume and weight.
While it is cooling due to heat shrinkage the layer is cracking and dividing into a geometrically irregular grain shapes.
In microgaps formed between the grains by capillary action comes copper, which is still in a liquid state, and is in near-surface micro- layer of material layers.

A large number of scholars did a lot of researches on cathode materials of SOFC.
Fig. 2-a showed the diameter of BaCe0.9Ta0.1O3+δ ceramic grains were around 3μm.
With the increase of doping amount, the size of ceramic grains was also growing.
However, the grain size of BaCe0.70Ta0.30O3+δ (Fig. 2-e) ceramic reached to 9μm.
The crystal grains closely combined together throughout the whole crystal boundary.

The structure of the welded joint formed by laser welding has a gradient highly non-equilibrium coarse-grained structure based on a-phase, grain size reaches ~600 × 280 µm (Figs. 1a and 1b).
The welded joint responds poorly to etching, a large number of pores are observed.
The welded joint structure is consertal after welding, fine grained nodular structure of ~1 - 3 μm size is near fusion zone (Fig. 4b).
The structure refinement with dislocation and α+β plate formation occurs inside coarse grains in the middle of the welded joint after Treatment 2 (Fig. 4c).

Bioceram Zirconia Al2O3 79, ZrO2 19, Others 2 Density g/cm3 4.25 3.98 6.08 Average Grain size micron 0.4 1.3 0.2 4-point Bending MPa 1200 600 1400 Fracture Toughness KIc MPa・m 0.5 4.7 3.7 4.2 Hardness Hv 1700 1900 1400 Young Modulus GPa 350 400 210 Characteristics Unit JMM-ZTA Bioceram Alumina ZrO2+HfO2 + Y2O3＞ 99.0 Chemical Composition wt% Al2O3 ＞ 99.5Fig.3 SEM photograph of JMM-ZTA crystal
The horizontal-axis shows the Hertizian contact stress obtained by each load applied, while the vertical-axis is the wear factor calculated by the volume of wear divided by the number of slides and load.
In a full dense density, the relationship between strength and diameter of crystal grain follows the Hall-Petch's law.
The SEM photograph shown in Figure 3 indicates that the average diameter of crystal grains of the JMM-ZTA is 0.4 µm which is far smaller than that of high purity alumina i.e. 1.4 µm.
As to the maximum tensile stress at the end of the contact area, assuming the Hertizian contact, the critical weight Wc required for spreading of cracks in the grain boundary, according to Hamilton et al.[4], is shown in the following formula. 3 23 )101(24       +    = d cK E R W Icc µ π (2) where, R is the radius of the tip of the pin, µ is the wear factor, d is the length of a pre-crack, E is the Young's modulus, and c is the constant.

A large number of domestic and foreign scholars’ experiments show that alloy’s properties can be improved and enhanced with the particles added[8-12].
The Zn/Al eutectics were distributed on the grain boundary, in Fig.1(a).
Higher magnification by SEM of as-spray-deposited TiB2/Zn-30Al-1Cu composites, Fig.2(a), revealed some particle-like compounds both on the grain boundaries and in the grain interiors.
Fig. 3 shows the TEM photographs of the particle-like compound phases on the grain boundaries.

The size of the grains is ranging from 50 nm to 200 nm.
The combination between ceramic grains is more closely.
A large amount of large grains can be seen in the two images, which is the proof of generating of CuAlO2 main phase.
Smaller particles indicate that the reactions can produced a small number of CuO mixed phase.
It can be found that the arrangement of ceramic grains are more denser and porosity content of ceramic is more less from SEM tests.

According to this group of researchers, a composite polymer electrolyte system with low filler concentration (1 wt % of TiO2) can be imagined as a conducting medium where filler grains were randomly and uniformly distributed.
The presence of the filler grains gave rise to additional favorable conducting pathways in the vicinity of the surface of the grains.
The number of such additional high conducting pathways increased with increase surface area of filler grains.