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In several studies [1, 2] the chemical analysis of number of numismatic materials have been performed with different methods (XRF, ICP, PIXE, NAA).
The standardless mode with the ZAF correction, which uses fundamental factors to correct the effects of atomic number (Z), absorption (A) and fluorescence (F) was used for chemical analysis.
All the coins of pure Cu have a recrystallized structure; the grains are not oriented and have the size of 10 - 80 microns.
All the Cu-Zn coins (Fig. 1) have recrystallized structure, with polygonal grains, slip lines and twins.
In some coins a moderate amount of recrystallized grains and slip lines have been detected.

The mean friction coefficient increases from 0.048 to over 0.1 according to the number of produced workpieces (Fig.3).
The dimensions of the black spots are consistent with the size of the WC grains.
Profilometry measurements show that WC grains have been removed in the form of scratches over 5µm deep.
The crack is propagating according to the WC grain boundaries when the indentation load is released [12].
The main surface damages appear first at the transition fillet including grain removal and Fe adhesion.

The boron diffusion in the Fe2B phase is of anisotropic nature and grains may exhibit finger-like growth with a (001) texture [13].
Therefore, the boride grains with the )001( direction perpendicular to the surface of the specimen grow faster.
The growth of the boride grains with other orientations is slower and soon suppressed because their growth meet other grains, resulting in a )001( texture structure.
In brittle polycrystalline materials, the microstructure affects the indentation cracks in a number of ways, such as crack termination at porosity and/or grain boundaries normal to the crack path and crack deflection along grain boundaries.
Niihara et al. [17,18] for the Palmqvist crack regime, the Young's modulus of the surface layer has been related with the HV number for the different applied loads and indentation distances from the borided surface.

Process of DLOM In order to improve efficiency, the laser only enters phase 2 after a certain number of layout at work station 1, shown in Fig.3, the layout numbers n can be calculated by: (1) where L is the width of platform 1 (the constant), W is the distance between the layout and the margin of work station 1 (the constant), and A is the distance between the external edges of adjacent layouts (the constant), bi is the width of each layer (the variable).
It is also observed that the grains in the welding zone are finer than those in the substrate.
Oversaturated C diffuses towards the austenitic grain boundary and combines with Cr forming Cr23C6 at the austenitic stainless steel heated temperature of around 450-850℃ under regular welding processing.
When the Cr content of less than 12% near grain boundary, it lost the corrosion resistance and almost complete loss of strength when stress in the subject that will fracture along grain boundaries[12].
And the resistance welding process, however, can be done in a very short time duration, which will not cause a lack of Cr at the grain boundary by avoiding the diffusing and clustering of C and Cr.

This alloy composition bears number of electrons per atom (e/a) equal to 7.655 which is chosen so as to achieve close to room temperature austenitic start (or martensitic start during cooling) [5], desired for practical applications.
It was observed that at the grain boundary there was a relative increase in the Nickel and Manganese concentration.
This was also supported by the higher content of element Ga in the grain matrix (table-II) as compared to the grain boundary.
The micrograph shown in fig-5a indicated granular structure with the grain (a) Martensitic plates 0.1µm (b) Fig-5: TEM micrograph showing (a) Grains interface (SAD at inset for grain matrix) and (b) grain boundary region Fig-4: Differential Thermal Analysis plots of as-Spun ribbon showing martensite to austenite transformation.
As the ribbon had indicated different elemental distributions at the grain matrix and the grain boundary therefore examination was carried out for the grain boundary and it was interesting to find welldefined stripe like morphology typically of martensitic phase [11] as shown in fig-5b.

The unit cell is a face-centered cubic arrangement of tetravalent cations with oxygen anions occupying tetrahedral sites, leading to a large number of octahedral interstitial voids.
The grain size of both layers is inhomogeneous and may result from the short dwell time during sintering that the process of grain growth is limited.
These two semicircular arcs are associated with the grain and grain boundary impedances in sequence.
RgCg and RgbCgb with the subscripts g and gb denoting the grain and the grain boundary, respectively.
All of the electrolytes exhibits two semicircle arcs corresponding to grain and grain boundary, respectively.

Therefore a great interest in new composite materials has been observed for a number of years.
Besides of metallic base matrix and calcium pyrophosphate in pores, the inclusions of new phases are visible on the grain boundaries as well as inside the grains (Fig. 2.c).
The chromium volume in steel grains decreased.
Inside grains there are visible numerous precipitates of iron-chromium posphides.
There are shown austenite grains and pores on the picture of non-modified sintered steel 316L.

Basically, glulam is obtained by stacking a number of laminations on top of each other and gluing them together so that they form a beam cross section of the desired shape.
Table 2 Test results of the beams Material type Ultimate moment [kN·m] Bending Strength[N/mm2] Modulus of elasticity [GPa] Failure modes Pseudotsuga menziesii glulam 21.4~35.4 36.7~60.7 average＞40 12～15 Bending failure Yi polar glulam 22.4~33.1 51.0~59.1 average＞55 10.2~10.7 Tension failure of lumber in finger joint Fast-growing Polar giulam 8.0~10.5 48.3~56 average＞52 9.5~13.2 Finger joint, knot or grain slope Fast-growing China fir glulam 9.6~16.4 23.75~41.55 average＞30 6.9~12.25 Tension failure of lumber in finger joint Remark: Table 2 is organized by referencing other literature. [1, 7, 9, 10] As can be seen in Table 1, it is stronger along the grain than across the grain.
All the timber listed in the the diagram are particularly strong in tension and compression paralled to the grain, and they have great bending strength.
Moreover, the failure of almost all the glulam beams were due to the defects, such as knots, grain slope and finger joints, in the tension area.
Pseudotsuga menziesii and larch can be recognized as good original timbers of glulam which not only have high modulus of elasticity but also good most outer bending fiber stress, rift grain tension, shear and compression of cross as well as rift grain.

Characteristics of morphological and geometric phases were evaluated using Good Grains software.
The average grain size is about 230 µm (with a spread of 100 to 400 µm).
The carbide phase inclusions are located both along the boundaries and along the grain body.
The complex carbide chromium-molybdenum phase, located at the grain boundaries, has a particle size of about 1 µm, and in the grain body is up to 3 µm in grain body.
The heat resistance is also directly dependent on the number of strengthening phases.

The island of internal oxidation was found owing to oxygen easily getting into substrate along grain boundary because of high defects in grain boundary and then high oxygen concentration.
Mass-gain as a function of the number of 1-hr cycles at 900˚C are presented in fig.2.
Oxidation corrosion was aggravated along grain boundary due to oxygen getting into substrate.
Grain boundary defects and the carbide were found in grain boundary, and then oxygen easily concentrated in grain boundary and then easily gets into substrate [1, 11].
Inner oxidation was found along grain boundary due to grain boundary defect and high-oxygen. 3) The hot-dipping aluminum sample composed of outer Al-rich layer and Ni2Al3 layer after diffusion annealing at 950˚C.