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Fig. 2 (b) Application to biomedical engineering: Hip-joint endoprostheses Nowadays, the annual number of prosthesis replacements of hip joints has greatly increased, whilst, at the same time the amount of operations grows constantly, mainly due to the process of natural aging of the society and increase in the number of technological and transportation-related accidents.
Shock loading leads to intense fracturing of the initial grains and stacking, leading to void decrease and to consolidation
Micrographs showing: the particle shapes after compaction, the metal jet formation and plastic deformation of grains due to impact, a jet head of molten material entrapped in a cavity formed due to impact, a channel of molten material with a column-like “as-cast” grain structure and the microstructural characteristics of the compact at the aluminium punch plate/powder interface are shown in Figs.7(b)-(f), respectively.
The shockwaves originated from explosive detonation and propagated through the porous media, can create high shock pressures and high temperatures that result in fracturing the original grains and in sintering.

Hot rolling and heat treatment Mechanical property tests -10°C lateral impact requirement, flattening is an alternative test Room temperature impact, vertical replacement for landscape Surface quality No internal oxide scale or annealing residue on the inner surface, surface roughness depth <10% wall thickness Surface defect depth <12.5% wall thickness Organizations and precipitations Single-phase austenite structure, the number of precipitated phases is required No special requirements They have strong corrosion resistance to chloride-induced stress corrosion and can withstand corrosive media such as carbon dioxide and hydrogen sulfide.
Alloying Elements in Nickel-Based Alloys and Their Effects The ISO 13680 standard stipulates that a continuous precipitation phase is not allowed at the grain boundary in the microstructure of the nickel-based alloy for oil country tubular goods material and the total content of intermetallic compounds, nitrides and carbides does not exceed 1.0wt%, and the σ phase does not exceed 0.5wt% [6].
D.Kong et al. [10] studied the effect of Nb content on microstructure and mechanical properties, indicating that the grain size of nickel-based alloys decreases with the increase of Nb.
When the alloy composition is unsatisfactory, the heat treatment is improper and large number of harmful different precipitation phases are generated in the austenite crystal or grain boundary (Fig. 2) [12], pipes are prone to stress corrosion and local corrosion in highly acidic corrosive environments.
Since the nickel-based alloy contains many alloying elements, after the hot extrusion process, the second phases distributed along the grain boundary often generate, such as nitride phase, carbide phase and σ, which may affect the resistance of the material.

In addition, in situ synthesized TiB and TiC reduce the grain size of matrix alloy.
In Fig.3(c), the TiB whiskers and TiC particles mainly distribute at the β grain boundaries.
This reveals these reinforcements played a role of obstacles and restricted the grains growth at high temperature.
A large number of cleavage planes appeared in the fracture surfaces of TMC-1 (Fig. 5(b)).
Large numbers of cracked TiB whiskers and TiC particles indicate that in most cases cracks initiated in reinforcements at first, then (a) (b) (c) propagated to matrix alloy and resulted in failure at last.

Because powder-bed process is used for manufacturing, component surfaces have certain amount of partially-connected (fused) precursor powder grains (60-100 mm in diameter), which resulted in a relatively rough surface morphology.
As clearly visible from the images metal surface contains a number of powder grains strongly and rather loosely attached to the bulk metal (Fig. 1) providing a roughness with the spectrum ranging from nanometers to about 100 mm, a feature quite common for the powder bed AM processes.
As clearly visible from the images metal surface contains a number of powder grains strongly and rather loosely attached to the bulk metal providing a roughness with the spectrum ranging from nanometers to about 100-130 mm, a feature quite common for the powder bed AM processes.
A comparison of the HA films on titanium substrate surfaces modified by acid etching and pulse electron beam treatment revealed significant differences in the morphology of the films (roughness, grain size and shape) and the mechanical properties [12].

Kroll’s etchant (2 vol% HF, 6 vol% HNO3 in H2O) was used to develop the grain structure for imaging.
The number of mesh elements and load steps were increased until results converged.
The second graph of Figure 4 shows the effect of increasing the size of the representative volume by an integer number of unit cells in the x, y and z directions respectively, where the load is applied along the z-axis.
Etching reveals a grain structure typical of Ti-6Al-4V produced by EBM [9].
Figure 6: (Left) Etched cross section showing the grain structure of porous EBM Ti-6Al-4V.

Results showed that: compared to conventional zinc phosphating process the solution was stability, all the ferrous iron was formed the film, and FePO4 had not precipitated in the phosphating system; the phase of the phosphate film was formed by the small grain which was Fe2Zn(PO4)2·4H2O and Zn3(PO4)2·4H2O mixed in the proportional spherical crystals to instead of the Zn3(PO4)2·4H2O-based that was needle-like or leaf-shaped loose crystals.
These literature used a number of ways to alleviate these shortcomings without break the original formation mechanism.
SEM Analysis of phosphate film In Fig.3(a) the SEM micrograph showed that the traditional zinc phosphate film was irregular leaf-shaped crystals, large and loose grain, and in Fig.3(b) the phosphate film in this study was uniform, dense small spherical crystal particle accumulation.

(3) where, P is the final product size distribution vector, K is the number of crushing layers.
During the breakage process of jaw crushers, if the particles size is well-distributed and the influence of grain distribution ratio is neglected.
The parameter Xi can be calculated by Eq. (6), where xi is the particle size, xmin is the minimum size of the grains that undergo breakage and xmax is an upper limit value of the feed size.
This is because the eccentric shaft velocity influences the actual compression ratio and the number of crushing layers.

The powders were then spreaded in a mortar and sieved in a #100 mesh sieve to standardize the size of the grains.
The tablets were metallized with carbon to be submitted to Scanning Electron Microscopy (SEM) for a visualization of the characteristics of the grains, as well as EDS to identify the chemical components which are present.
With the Vickers microhardness tests of sintered Ca2AlZrO5,5 it was possible to determine an average hardness number of 160 Kgf/mm².
This number is considered reasonable compared to other ceramics with similar properties already researched.

Table 1 Impermeability test result of concrete name number Volume mix amount Test age d Osmotic pressure MPa Water seepage depth mm 1 0 28 1.2 27 2 40 28 1.2 21 3 45 28 1.2 19 4 50 28 1.2 28 5 40 28 1.2 43 6 45 28 1.2 58 7 50 28 1.2 56 Attention：（1）1 was normal concrete without fly ash; （2）2,3 and 4 were separation fly ash; （3）5.6 and 7 were original state fly ash.
Table 2 Carbonation test result name number Compressive strength 180 days age Average carbonation depth mm Resist carbonation effect coefficient 28 days No carbonation Carbonation 28 days 3d 7d 14d 28d 1 62.5 67.2 0.5 1.0 1.0 1.5 2 65.3 76.7 2.4 2.5 3.2 4.2 2.8 3 64.8 69.8 4.4 4.3 4.3 4.4 2.7 4 63.7 64.1 4.6 5.5 5.6 5.8 3.9 5 63.5 75.1 1.0 1.6 2.2 4.2 2.8 6 58.1 69.4 3.1 4.4 4.8 5.1 3.4 7 51.3 62.7 4.5 5.3 5.6 7.2 4.8 This was carbonation time and depth graph of relation 1 under all age.
Because mean grain size of separation fly ash Dsv was 6.0μm, mean grain size of original fly ash was 16.4μm.

Now the analysis and research of the number of particles and various characteristic parameters on the microscopic image is among the hot topics around the world recently[3].
(c)grinding 15min X200 (d)grinding 20min X400 (a)grinding 5min X200 (b)grinding 10min X200 Fig 1 SEM Images of Ball Mill Slag Powder B Digital Processing Research of Particle Image Histogram Equalization Histogram of the image is used for calculating the gray-scale probability and number, improving the quality of the image and weakening other irrelevant information, thus it enhanced the outstanding information of the image, and provides us with a lot of statistical information about image and characteristics parameters of the micro particle.
Tab.1 Micro- appearance Quantization Parameter of Slag Morphology quantitative parameters computing method Shape factor Roundness factor Flat degree Edge angle Surface roughness P represents the perimeter of the grain boundaries, A represents the particle size, L and B respectively represents the maximum and minimum particle diameter Fred, represents minimum circumscribed polygon perimeter of particle, represents the circumference of the equivalent ellipse.
An exact method for characterization of grain shape[J].