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This paper presents a very concise summary of the present knowledge in the form of an approach to a comprehensive scale failure model which is based on a number of microscopic and macroscopic system parameters.
The intention of this paper is to present a very concise summary of the present knowledge in the form of an approach to a comprehensive scale failure model which is based on a number of microscopic and macroscopic system parameters.
Figure 4: Ashby Map, for type 316 stainless steel, grain size 200µm At the same time, stress values can be entered into these "Ashby" maps corresponding to a critical oxide stress (failure stress) calculated from the critical oxide strain multiplied by the Young's modulus of the oxide.
Conclusions As intended the paper has presented a very concise summary of a state-of-the art approach to a comprehensive scale failure model based on a number of microscopic and macroscopic system parameters.

It has been reported that the fracture happened from surface at high- stress amplitude level and low number of cycles; fracture occurred from internal at low-stress amplitude level and high number of cycles.
It can be seen from the photographs that many spherical carbide particles are distributed in the matrix which is tempered martensite structure and the prior-austenitic grain size is 5.62µm.
So it is expected that the crack will 10 6 107 10 8 0 10 20 30 40 50 Number of cycles to failure N f,cycles Size of GBF area √areaGBF, μm 105 106 107 108 109 1 2 4 10 Number of cycles to failure N f,cycles ⊿Kini and ⊿KGBF,MPa√m Surface,⊿Kini,s , Subsurface,⊿Kini,i GBF,⊿KGBF 5 7 Fig.8: Relationship between the stressintensity factor range at the crack initiation sites and the number of cycles to failure.
Fig.7: Relationship between size of GBF area and the number of cycles to failure. 105 106 107 10 8 10 9 0 100 200 Number of cycles to failure Nf,cycles Depth of inclusion dinc,μm SUJ2 Fig.5 Relationship between depth of inclu- sion initiated crack and number of cycles to failure. 105 10 6 10 7 108 0 10 20 30 40 50 Surface Subsurface GBF Number of cycles to failure N f,cycles Size of initial crack area √areaini, μm SUJ2 Fig.6: Relationship between the size of inclusion initial crack and number of cycles to failure.
The number in each plot of figure gives the topographic displacement relative to the reference state.

Research on the Wall Crack Grouting Technology of Brick-concrete Structure Bin Jia1, Ke Li1, Xiao Liu1 , Naiqing Meng2 1School of civil Engineering and Architecture, Southwest University of Science and Technology, Mianyang 621010, China 2The construction engineering earthquake office of Tibet autonomous region, Tibet Lhasa 850000,China Keywords: Masonry structure, Cracks, Grouting Abstract: Wenchuan earthquake caused a large number of masonry structure cracks, crack grouting become a very important link in the process of engineering structure reinforcement repair.
Sand grain size mortar is set according to the situation, generally used in the medium sand and medium sand in the following.

Microstructure of the WE43 (Mg-4Y-3RE) alloy in the as-cast state consists of solid solution grain Mg(α), yttrium (~0.7% at.) and neodymium (~0.3% at.) in magnesium, and eutectic Mg(α) + β (Mg12NdY) (Fig. 2b).
The number of repaired castings and welded structures is not satisfactory, which often makes production unprofitable.
The weld area has a significant grain fragmentation (Fig. 3c).

As we all known, diameter of particles can be calculated with Schrrer formula: Where D is the vertical direction of the grain size；λ is the wavelength of the x-diffraction ray；β is the diffraction peak width at half maximum；θ is the diffraction angle.
The introduction of Co, Ce can inhibit the TiO2 phase transition from anatase to rutile, and prevent the grains growth and agglomeration.
Oxygen adsorption is increased in the surface of composite particles, which can capture the photoinduced electrons to prevent the recombination with holes, and generate a large number of reactive radical species to promote the photo-oxidation degradation of organic matters.

As known from linear, irreversible thermodynamics [8], the driving forces for the motion of charged species (index i) are the gradients of their electrochemical potentials, , where mi is the chemical potential, zi the charge number, F Faraday’s constant, and F the electric potential.
If the formation of the oxide layers is determined by bulk and/or grain-boundary diffusion processes, one obtains parabolic rate laws for the thickness of each oxide, Dxi(t) = (2kit)1/2 (i = CoO, Co3O4).
As discussed there, the relatively high value is probably due to a significant contribution of fast cation diffusion along grain boundaries within Co3O4.

In process of ultra-high speed grinding, keeping the other parameters unchanged, the chip thickness of every grinding particle will become thinning out with the grinding speed’s great improving, active grains’ increasing in unit-time and the thickness of the wear debris ‘being smalling cutted by abrasive grit.
High speed grinding has the following outstanding technical advantages compared with ordinary grinding [19]: High speed grinding can greatly improve the grinding efficiency and reduce the equipment number.
In the same material removal rate .High-speed grinding can reduce the cutting depth of single grains, thereby reducing the grinding force and getting the high quality of the workpiece surface .Especially in machining the lower stiffness (such as thin-walled parts )of the workpiece.

The electrical conductivity depends on the heating temperature (T), the heating rate (T) and the grain size of the material.
The relative permeability depends on the frequency (f), the magnetic field strength (H), the heating temperature (T) and the grain size in the material.
Furthermore, using an experimental design based on strategies such as orthogonal arrays (MO) developed by Taguchi, usually leads to designs like fractional effective and robust to obtain statistically significant information with a minimum number of simulations.

It is well known that aluminum alloys can be strengthened by a number of mechanisms such as particle dispersion hardening, solute hardening, age hardening precipitates and grain size reduction.
Among these strengthening mechanisms the age hardening precipitates and grain size reduction in the production of fin stocks for automotive applications are difficult to obtain due to the high temperature brazing treatment.

.), in-situ plant measurement of soundness on directly as-cast products remain challenging in view of as-cast product shape/surfaces (ingots) but mostly signal attenuation due to grain structure.
(a) (b) (c) (d) Fig. 2: Experimental laboratory testing for consolidation: (a-b) on steel billet/ingots with drilled hole(s) of given size/distribution, (c-d) drilled tensile/compression or split Gleeble specimens [3] Table 1: Key parameters and constraints affecting consolidation of porosity (RX: recrystallization, GS: Grain size, TNR: Non recrystallisation temperature) At Tata Steel UK, specific attention has recently been paid on ways to provide rapid consolidation guidelines to roll pass designers for optimizing pass scheduling within mill constraints as well as developing a more in-depth understanding of soundness through ingot solidification and rolling incorporating void closure and healing.
Typical values of hm/L for initial cogging/breakdown ingot/bloom schedules are most likely greater than 2 and therefore depending on overall reduction, consolidation of central porosity might not be complete even after cumulative number of passes.