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The surface of the work piece had concaves caused by silicon particles shedding and grooves caused by the grains observed by the SEM and CLSM.
Table 2 Grinding wheels used in the experiments Grinding wheel Grain * Grit size Bond Diameter x Width(mm) alumina wheel WA 46# Vitrified-bond 200x30 PA 60# Vitrified-bond 200x30 Silicon carbide wheel GC 80# Vitrified-bond 200x30 C 60# Vitrified-bond 200x30 The peripheral wheel speed was 17.83 m/s.
It can be found that there are concaves caused by the silicon particles shedding and grooves caused by the grains.
The number of the concaves on the surface grinding by the chromium alumina wheel is larger than those on the surface grinding by the SiC wheel.
The concaves caused by the silicon particles shedding and grooves caused by the grains can be observed through CLSM.

The grain size was characterized by transmission electron microscopy (TEM) (JEM-2000EXⅡ).
The grain size was not uniform, which changed from 20 to100µm.
The EPMA results [10] indicate Cr element is obviously depleted at the grain-boundary of the cast alloy, while Al and Ti are clearly depleted at the grain.
Its grain size is three magnitudes smaller than that of the cast alloy.
Nanocrystallization increased the number of possible nucleation sites of the oxide, because of an increased concentration of grain boundaries on the alloy surface[12], so the initial nucleation sites for oxides formed on the sputtered coating were certainly much more than those on the cast alloy.

Experimental procedure The complex investigation of the impact of maintenance and repair heat-ups on the structure and properties of thermal impact zones of chrome-nickel steel involved the testing of samples produced from a number of experimental melts of chrome-nickel steels containing from 11% to 25% of nickel.
Under increased heating temperature up to 650 °C and holding time up to 10 hours, the grain boundaries suffer the formation of ripped carbide network.
The further increase of temperature up to 700 °C leads to gradual coagulation of carbide inclusions, and spherical Ме23С6 carbides substitute the grain-boundary carbide network.
This zone (Fig. 3) differs from other zones of basic metal and the welding joint by the steep grain growth, and, consequently, a sharp increase in the level of grain boundary segregation of doping elements in its boundaries.
Nickel facilitates the diffusion of carbon into grain boundaries, thereby reducing the alloying element content and loss of grain boundary strength, increasing the concentration of impurity elements (sulfur, phosphorus, etc.) and further reducing the cohesion of the boundaries. 3.

Introduction Modern, fine-grained structural steels are characterised by a unique strength properties.
Introducing the possibility of the occurrence of residual strength of the material in which plastic deformation may occur requires carrying out a fatigue test in the range of a small number of load cycles at the predetermined failure criterion.
Purpose and research methodology The aim of the study is to determine the fatigue properties of fine-grained, martensitic-bainitic structural steel S960QL and to assess its fatigue cracking.
Strength properties of S960QL steel E [MPa] Rp0.2 [MPa] Rm [MPa] A [%] Z [%] According to the certificate - 997 1069 13.0 - Own tests 2.20x105 974 1070 14.2 45.6 The tested S960QL steel is characterised by fine-grained martensitic-bainitic structure with a equivalent diameter to a grain size in the range of 10-25 μm.
In both cases, cracking is accompanied by numerous secondary cracks (SC), whereas at high strains these cracks run mainly along the grain boundaries (GB) (Fig. 6d).

The two resulting types of TiB2 underwent a laser grain size analysis by a Mastersizer 2000 unit.
A quantitative analysis of the microstructure of the composite was performed, and some selected micro-structural parameters were measured, i.e.: VV (TiB2) volume fraction; E(d2) average equivalent diameter of a flat cross-section of the particles; E(D) average equivalent diameter of particles in three-dimensional space; a average cross-sectional aspect ratio of the particle; NA number of particles in the plane sections of the unit; NV number of particles in unit volume.
In all the tested types of SiC-TiB2 composites, the average particle aspect factor of TiB2 grains has a similar value in the range from 1.43 to 1.49; it means that the difference in the preparation of titanium boride powder does not affect on the shape of the particles of this phase in the sinter.
The microstructures of the materials show some important characteristics such as: high degree densification of the composite, homogeneous arrangement of particles of the dispersed phase, and fine-grained microstructure of composite.
The milling of TiB2 powder caused the secondary agglomerates of grains to form, however, it did not affect the phase grain size of the strengthening material. 3.

This is because the slight reduction of the Cu sputtering rate caused by the increase of the number of the Ni rings on the Cu target.
The average grain sizes were estimated by the Scherrer formula[4] of the four samples and the calculation results are listed in table 1.
The results show that the sizes of the grains are in the nanoscale size and increases from 16.3 to 25.7 nm with the increasing concentration of Ni and these results are consistent with the SEM images shown in Fig.2.
As seen from Fig. 2a, the surface of undoped Cu3N film is composed of pyramid-like grains.
When the Ni-doping content in Cu3N film reaches 2.32%, the crystalline grains vary from pyramid-like to rugby ball like as shown in Fig.2b.

The number of pores decreases with increasing ZBS glass content and a dense microstructure without pore ss developed in the specimen with 8wt% ZBS glass.
The grain sizes of CLLNT increase with the increment of ZBS glass, while is smaller than that in the pure CLLNT ceramic specimen sintered at 1400ºC for 4h.
For the specimen doped by 10wt% ZBS glass, a little hetero-shape grains (marked by an arrow) occur, as shown in Fig.3(d).
As the amount of ZBS glass increases to 12wt%, many hetero-shape grains are observed.
The ZBS glass melts formed and enhanced the densification and mass transportation resulting in the Q×f increase due to the reduction of the number and size of pore in the ZBS doped CLLNT ceramic specimens, while the adding of ZBS glass resulted in the lowering Q×f of CLLNT ceramic due to its lower Q×f value comparing with CLLNT.

The Failure Probability, Fp is the numerical rank divided by n+1, where n is totals number of specimens.
In this case, total number of specimen were 10 for horizontal samples and 20 for vertical samples.
Aluminium LM6 (Al-12Si) Grain Structure.
Fig. 5 shows the grain structure of unmodified Aluminium LM6 (Al-12Si) alloys produced in this project.
Experimental and testing works have been conducted to investigate the mechanical strength, grain structure and defects pattern of the alloy castings material.

Table 1 Statistics of the heavy oil block pilot test wells sand-production inspection Well number T4-2121 T4-2122 T4-2123 T4-2124 Total Times of inspection 4 2 5 4 15 Cumulative sand column height (m) 31.5 28 163.5 34.4 257.4 Technology and Measurement For the development of the medium-deep heavy oil reservoir, because of high viscosity and sand-carrying ability, the result of CHOPS and conventional thermal recovery is very poor.Improving the oil mobility is the key to the success of the entire development.
Selecting the prepacked gravel size is 4 ~ 8 times of the formation median grain size [1].
(3) Where, —critical flow velocity; —grain average concentration; —grain sedimentation blocked index; —dynamic viscosity, ; —acceleration of gravity, ; —average grain diameter, m; —the density difference between grain and liquid, kg/m3; —the liquid density, kg/m3; —casting inner diameter, m; —tubing outer diameter, m.
Table 2 Total production statistics of pilot test in Xiaermen Qianbei block Well number Test Before Test After Cumulative oil production /tons Cycle oil production /tons Daily oil production /tons Oil-Steam ratio Cycle oil production /tons Daily oil production /tons Oil-Steam ratio T4-2121 240.3 4.15 0.17 868.4 9.44 0.65 1473.9 T4-2122 124.4 1.87 0.06 775.54 5.21 0.63 2472.3 T4-2123 107.1 1.12 0.02 508.7 4.61 0.40 1741.5 T4-2124 258.2 3.52 0.19 343.0 3.82 0.35 1532.3 Conclusion In the pilot test, improving the mobility of the heavy oil in the formation and wellbore is the key issue of the medium-deep heavy oil development.

It is assumed that the internal stress is generated in the initial stage in which the plating grains with a thickness of about 0.01µm deposit.
It is assumed that the internal stress is generated in the initial stage in which the plating grains with a thickness of about 0.01 ㎛ deposit.
φ is obtained by counting the number of interference fringes because the brightness of the interference fringe changes when the phase becomes 2π.
After 5 minutes, the grain size of the basic solution and additive solution is clearly bigger than these of the commercial solution.
(3) The growth rate of the grain size in the basic solution and the additive solution is higher than for the commercial solution.