Search results

The surface of the mc-Si wafer contains many small parts of irregular grain regions under the RGB Color Model or Gray Model.
Therefore the linear combination of the three RGB passages will also contain irregular grain regions.
The grain boundaries of mc-Si wafers resulted from the disaccordant angles of surface incident light and reflect light instead of color inconformity.
Therefore the intervention of grain regions was totally eliminated from S-passage.
Comparing to the segmentation on gray images, the segmentation operation on S- passage could lower the number of suspected regions, improving the inspection efficiency.

The property of the ring blank is improved because the crystal grains are crushed from coarse-grained to fine grained under the action of the shearing and extrusion compound forming.
It is shown that the effective strain increases with the punch working angle decrease, which benefits to refining the grain.
(Item number: 50675146) References [1] H.
Volume 12 Number 2 1999: 87-90

Normalizing treatment after welding had played an important role in refining grain size to the weld regions and base metal, and the mechanical properties of the material had been improved.
It can be seen from Fig. 4(a), the microstructure of weld was typical columnar crystals, which included a large number of acicular ferrite and a small amount of pearlite.
In Fig. 4(b), (c),the microstructure of HAZ and base metal were pearlite, however the grain size of HAZ and weld regions were smaller than base metal.
It can be seen from Fig. 5(a), the microstructure of weld was transformed from acicular ferrite to proeutectoid ferrite and a large number of pearlite formed after normalizing treatment.
Conclusions (1) The welding seam microstructure with no heat treatment was acicular ferrite with fine grains, and the HAZ area was pearlite with finer grains.

Biological studies showed that the number of cells cultured on the surface of HA samples with 1.8 wt % Mg additive, probably due to the MgO content, was lower than on the pure HA ceramics.
After 7 days of culture the cell number (DNA content – PicoGreen test) and viability (XTT test) were determined.
SEM investigations showed that the material based on modified hydroxyapatite contained larger and smaller grains.
In SEM images, at the grain boundaries and on the surface of hydroxyapatite grains, many micropores (about 1µm in diameter) were visible.
• Biological tests showed that the number of cells cultured on the surface of HA samples modified with 1.8 wt % Mg, probably due to - MgO content, was lower than on the unmodified HA ceramics.

SSM are built for the given strain and initial grain size.
Investigations of saturation processes of steels by nitrogen, of liquid- and solid phase reactions in multicomponent iron alloys, of structure states and transformations during deformation and heat actions have allowed receiving a number of basic results [3-6].
For quenched and rolled samples: dLR, kf - average grain size and form-factor after longitudinal rolling with 50 % reduction; dRSR - grain size after radial-shear rolling with 65 % strain; dquen - grain size after quenching.
Decreasing of the diffusional mobility retards dislocation climbing and grain boundary and subboundary migration.
In cases marked by (3), the recrystallized grain size is too large for the dynamic recrystallization.

The hardness of multilayers increased with a number of interfaces, but only when interfaces were clearly defined.
The interfaces between layers, as a barriers for dislocation motion, were taken into consideration instead of grain boundaries.
The relationship linking grain size with yield and hardness is well known: (1) where: H0 is a hardness of polycrystalline material, D – grain size and coefficient k presents the impact of grain boundaries on strengthening.
It is replaced by a practically uniform, fine-grained mixture of the two materials.
The number of interfaces was varying by changing multilayers bilayer period from 500nm to 32nm, whereas the microstructure effect was studied on coatings with the same number of interfaces but different thickness ratio of ceramic to metal layers.

In summary, liquid phase sintering can constrain the grains growth and diminish grains size.
Clear grain boundaries and plump grains can be observed.
It can also be noted that the grains become slightly larger with increasing sintering temperature(the grain size of (a) is 1~6μm, and that of (d) is 1~9μm).
It is well known that large grains can effectively reduce the space charges and impurity defects in the grain boundaries, and relax the polarization reversal of ferroelectric domains.
However, the liquid phase in grain boundaries volatilize rapidly due to over-high sintering temperature, which produce a number of pores and decrease the density.

The grain is considered as a two-phase material (dislocation walls and cells).
The grain undergoes a deformation εεεε (with a stress σσσσ) composed of an elastic deformation εεεεe and a plastic part εεεεp .
It should be noticed that the subscripts g and h vary from one to N (N: number of active systems for each phase 'c' and 'w') for each term of the expression (13).
The grains 1 and 2 correspond, respectively, to one of the less and the most deformed crystallites.
The grain 3 has an intermediate value of deformation.

(d)We consider a ferrite grain without pearlite grains surrounding as an “isolated” grain, and corrosion reaction, which is disconnected with pearlite, will take place at its region since random atom arrangement and atom defect.
(d) A state function S(X) is used to denote the grain type of a cell, X.
We assume there are about 4500 grains in Ω
(4)Once S(X) changes, total number of cells whose S(X) values are same should be calculated to make sure that size of a grain is not too big
(6)If a ferrite cell is either the “isolated” grain ferrite cell or the cell at the situation of step (5), corrosion reaction will take place in grain region.

In actual application, the indirect method is generally use to determine the the carbon content.The main indirect methods are infrared spectroscopy, chemical formula the number of P atoms fixed method (EPMA) and powder X-ray diffraction contrast method.
With the increase of CO32- content, the crystallinity and the grain size of CHAP decreases.
(3) In equation (3): is driving force;is gas constant (8.314 J·K-1·mol-1);is absolute temperature;is the number of the ion of constituent units in sediments;is the solubility product of ion in solution formed by solid-phase;is solubility product; is degree of supersaturation. 1 2 3 4 Fig. 2 TEM image of CHAP 1-C%=6.079%; 2-C%=6.135%; 3-C%=6.334%; 4-C%=6.452% The composition of the sample.
Through XRD, TEM, FTIR characterization of the CHAP analysis shows that, with the carbon content (CO32- content) increased, structural distortion of CHAP is enhanced, the crystallinity is lower, the grain size and grain diameter are smaller, stability and decomposition temperature are lower also.