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The surface morphology at inner and outer bend also had shown slip bands inside grains as shown in Fig. 6.
Fig.3: SEM photograph showing numerous micro cracks near to the crack edge (a), secondary crack near to the fracture edge (b) Fig.5: SEM photograph showing fatigue striations on fracture surface Fig.4: SEM photograph showing the presence of slip bands on the surface and secondary crack propagation along the slip bands Optical microscopic observations Optical microscopic observations on the un-etched specimen revealed that the raw material used for fabrication was clean with respect to non-metallic inclusions .When electrolytically etched with oxalic acid, the microstructure revealed typical austenitic grain structure as shown in Fig 7.
Fig.6: SEM photograph showing the slip bands inside the grains Fig.7: Optical photograph showing microstructure of the bellow a b Fig.8: Optical photograph of the inner bend (a) and outer bend (b) showing the thickness variation along the bend length of the failed bellow.
The raw material was very clean without any inclusions and microstructure of the material was typical austenitic grain structure.
Presence of large number of slips bands within the grains is attributed to easy initiation and propagation of fatigue cracks [1].

After diamond grains are purified, the surface topographies of the diamond grains were observed with the S4800 field emission scanning electron microscope.
There are two hills composed of step layers in Fig. 5, and the number of step layers is different.
For the view of two two-dimensional nuclear, the number of two-dimensional nucleus formed on the step are different, so the numbers of layers in the hills are not the same.
For the two two-dimensional nuclear growing separately, the numbers of two-dimensional nucleus formed on the step are different, so the numbers of layers in the hills are not the same.
Synthesis and characterizing of diamond single crystal with ultra-fine grain size under high pressure and high temperature.

Laboratory test results of sludge from grit from the Wastewater Treatment Plant ”Warta” SA in Czestochowa Number Indicator Unot Methodology Result 1.
Formulation of concrete mixture for implementation in the principal road foundation Component Weight of mixture for 1m3 Percentage of processed waste as a replacement Cement 270 kg - Water 157 kg - Fine aggregate: 0-4 mm grains 587 kg 5-10 % Average aggregate: 4-8 mm grains 548 kg - Coarse aggregate: 8-32 mm grains 823 kg - Implementation of the road model A practical test of the new waste management technology of grit was the implementation of concrete road model built on the treatment plant’s property.
The road’s foundation consisted of three sections made to compare between the different sets of materials: - concrete according to the recipe shown in Table 1 without the waste substitute taking part, - concrete containing recycled waste from grit, used as a replacement for 5% of fine aggregate grains of 0-4 mm, - concrete containing recycled waste from grit, used as a replacement for 10% of fine aggregate grains of 0-4 mm.
The heading of "comparative concrete" means ready-mix concrete without the participation of the processed waste, "concrete composite 1" means the concrete content of the treated waste from the sand trap, used as a replacement for 5% by weight of fine aggregate with grains of 0-4 mm, and the "concrete composite 2" means concrete content of the treated waste from the sand trap, used as a replacement for 10% by weight of fine aggregate grains of 0-4 mm.

In the aging state, the average grain size of the Sn-rich phase was larger as the aging time increased.
It is well known that the larger grain size provides the lower mechanical strength and hardness.
The grain size of primary Sn decreased with Ni，Ni-B addition and the grain size of Sn-1.0Ag-0.5Cu- 0.05Ni-0.02B alloy was the finest of the three solder alloy systems(Fig.3(c)).
The intermetallic particles migrate to the grain and phase boundaries and shaped network-like, so as to impede the grain growth.
(c) (b) (a) Fig.5 Chemical composition evolution of the IMC layer: (a) Sn-1.0Ag-0.5Cu, (b) Sn-1.0Ag-0.5Cu-0.05Ni, (c) Sn-1.0Ag-0.5Cu-0.05Ni-0.02B Studies have found that Ni atoms can take the place of Cu atoms to form (Cux,Ni1-x)6Sn5 because of the same crystal structure and nearly similar atomic numbers of Ni and Cu[6,7].

With the increasing of cold rolling reduction, the distortion of grain got more severely.
As can be seen from Fig.3, deformation degree has great influence on the recrystallized grain size.
After exceeding the critical deformation, the grains gradually refined.
The higher the annealing temperature was, the smaller recrystallization grains were.
Acknowledgment Funded projects provided by State Key Lab of rolling and Automation (Northeastern University), serial number: 2009004 References [1] Tian Dexin, Feng Peihua, Liu Hui.

The relative density of the sintered specimens exceeded 99% of the theoretical value, with a mean grain size of 0.51 µm.
As a result, tetragonal grains on the ground surface are partitioned and highly distorted, but the amount of transformed monoclinic zirconia is negligible.
However, based on reported inherent strength of about 2400 MPa for the Y-TZP ceramic used by these authors it can be assumed that their material was extremely fine-grained.
In contrast, a steady decrease in the survival rate with the number of loading cycles was observed after accelerated ageing in artificial saliva at 134ºC prior to fatigue testing.
In addition, the tetragonal grains on the surface are partitioned and distorted, indicating that the reverse m-t transformation has occurred.

Ionic bombardment with low energy of growing the films can limit the grain raise and promote formation of nano-crystalline layer [1, 2].
The basic feature of such coatings is their ultrafine grained structure.
The grains sizes are within 60-80 nanometers compared to 100-120 nanometers for the commonly used (TiAl)N coatings.
The coating with a fine granular structure has greater extent of the grain boundaries.
In Fig. 2 a) and b) a number of secondary ions positive spectra as for commonly used and filtered (TiAl)N coatings is presented.

But recent experiments on grain boundary diffusion in the systems Al-Cu, Co-Cu and Fe-Cu, being performed at relatively low temperatures have shown that concentration in the diffusion zone can exceed the solubility at given temperatures [5-7].
Experimental Results Aluminum plates (99,8% purity) were recrystallized at 600 °C for 3 h to obtain the equilibrium structure with large grains (about 1 mm).
Acknowledgement This study was carried out with financial support of Russian Foundation of Basic Research (Project 15-03-08778) with the use of the equipment of Common-Use Scientific Center ‘‘Material Science and Metallurgy’’ at NUST ‘‘MISiS’’ (identification number RFMEFI59414X0007).
Gontar’, Cu diffusion along Al grain boundaries, J.
Rodin, Bulk and grain boundary diffusion of Co in Cu, J.

The Q „complex quality score” is derived from the (3) and (4) equation relationships m=1 approximation by: , (5) where C(t) is the abrasive particles merge average-speed [1], - parameter is expressing the particles increase of diffusion and decay rate, f – scratch hardness, the hardness of the honed material is proportional to the specific strength of the material, L – the way of interaction between the grains and workpiece, - with the heat transfer and the surface friction, the heat abstraction is an inversely proportional factor, approximate value of exponent: a=4 and b=5.
With the help of (5) equation it is diagnosable, that the complex quality score or the „tool machining” ability: - depends on the and L honing parameters: the proportionally gets better by normal direction force (with p) while L gradually gets worse by the increase of the contact length between the grain and the workpiece; - depend on the honing parameters Fn and L: it proportionally improves by the normal force Fn (p) and gradually deteriorates with the increase of interaction length (L) between the grain and workpiece; - C particles improve exponentially with an increase in average level of sharpness; - particle material proportionally gets worse, with an increase in diffusion and decay constants; - strongly gets worse because of temperature factor (it is better to have a higher heat capacity and heat dissipation, or worse if the friction between the abrasive particle and the processed surface is big; - It gets worse if the honing material’s f scratch hardness is larger which
Substituting the one’s before in the (6) equation and using (3) and (4) equation’s also, we get one-variable equation: (9) The previous equation, if divided by V=V(t) – we get the Cd – specific honing expense with the detached material’s cubic capacity (€/mm3): . (10) The honing expense’s minimum place is given by the following differential equation: . (11) After conversion and can be expressed „honing ratio” or goodness indicator: . (12) - the optimal material deception speed arises similarly: (13) and the optimal (minimum) honing cost: . (14) It can be read out from equation (3), that the G – honing ratio or goodness indicator is a dimensionless number.
Summary A great number of factors are effecting the honing process, and its aim, resultness (prescribed accuracy and surface quality, minimal machining cost).
Lausanne Switzerland, pp. 629-639 [9] Szabó O., Optimisation of Technology and „Quasi Honing” of Polygon Bores, Journal of Materials Processing Technology, ELSEVIR, Dublin, 2001. 119.1-3. pp.117-121 [10] Szabó O., Stability Criteria and Break out of Grains of Super-Hard of Grinding Tools.

Dashed boxes show the size range where more number of precipitates distribvuted.
As it is well understood, the precipitates have a powerful pinning effect on austenite grain boundaries.
Therefore, after re-heating to higher temperature, where more number of precipitates dissolved in the matrix (Fig. 2), the austenite grains can grow to larger sizes, so that bigger austenite grain size exits at the beginning of deformation.
Also, the role of precipitates, which can act as nucleation sites for DRX grains, could be considered as a factor accelerating the recrystallization rate in samples re-heated at lower temperature. 0 2 4 6 8 10 0 10 20 30 40 50 Area of Precipitates (µµµµm2 ) Aspect Ratio (λλλλ) Deformed Non Deformed Deformed non-deformed 0.0 0.5 1.0 1.5 0 20 40 60 80 100 120 140 Reheating @ 1100 oC Reheating @ 1250 oC Stress (Mpa) Strain εp εp Strain rate = 1 s-1 Deformation temperature = 1000 °°°°C 0.0 0.5 1.0 1.5 0 20 40 60 80 100 120 140 Reheating @ 1100 oC Reheating @ 1250 oC Stress (Mpa) Strain εp εp Strain rate = 1 s-1 Deformation temperature = 1000 °°°°C Fig. 3 The influence of hot deformation at 1000°C on the aspect ratio of centerline precipitates Fig. 4 Flow curves of centerline samples deformed after re-heating to different temperatures An important aspect of the behavior of precipitates during hot deformation