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MeF4M metallographic microscope and image analysis system were used to analyze the structure, grain size, non-metallic inclusions and weld joint structure of the pipe body according to ASTM E3-11-2011, ASTM E45-13 and ASTM E112-13-2013.
As shown in Fig. 6, ferrite + pearlite (F+P) in tubular structure, grain size is 10.5; As Fig.7 shown, the microstructure of leakage area is ferrite + pearlite (F+P), grain size is 11.5.
A large number of corrosion pits were found on the inner surface near the leakage, as shown in Fig. 9.
In addition, a large number of minor pitting marks were found in the area near the puncture leakage.

The material microstructure of the hot compression test samples was analysed, and the averaged grain size was calculated to compare with friction stir weld nuggets.
Introduction A number of studies on hot workability have been accomplished to illustrate the material flow stress characterisation[1-3].
The subgrain size are particularly important to prescribe the microstructural evolution during hot deformation, since it is highly relevant to most material mechanical properties[13], and the recrystallized grain size is also determined (before grain growth) by the subgrain size developed during deformation[14].
It is because of the  precipitate particles at the grain/subgrain boundaries which prevent further boundary migration and therefore inhibit recrystallization.

To Stachowiak and Batcheclor [19], the term “erosive wear” refers to an unspecified number of wear mechanisms which occur when relatively small particles impact against mechanical components.
Characterization of the coating showed that the average carbide grain sizes of the coatings were 0.8, 1.4 and 2.8μm and that a decrease in carbide grain size led to slightly higher degree of decomposition of WC.
The specific wear rate of the coatings was very low 10−6mm3/ (Nm) and increased with increasing carbide grain size.
The benefits of smaller WC grains in the hard-metal were further demonstrated by Jia and Ficher [63] where hard-metals with nanosized WC grains (0.07μm) exhibited improved wear resistance when compared to hard-metals with larger grain sizes for abrasion with a range of abrasive types.
Effect of carbide grain size on microstructure and sliding wear behavior of HVOF sprayed WC-12% Co coatings.

The results show that when the temperature of heat treatment quenching and tempering is too low, a large number of alloying elements cannot be fully integrated into the austenite, and the optimal obdurability of F92 steel is still not fully exploited; while too high temperature of heat treatment quenching and tempering will weaken the strength, plasticity and toughness.
From the photographs of microstructure, it can be seen that their tissue is formed by tempered martensite and the grain boundaries of the tissue are not clear.
Figure 5 shows that the SEM of the fracture tissue caused by one impact in F92 steel when processed by heating quenching at1050 ℃ and tempering at 680 ℃ takes the shape of a river with a certain ductile dimple fracture, and the smaller the dimple size is, the finer the grain of the tissue.

It has been reported that diamond films with micron grains and coarse surface were deposited on 6H-SiC single crystalline and ceramic substrate [7,8].
When the gas pressure is 1kPa, the spectrum shows another weak peak at 1140cm-1 which are thought to be related to the nanocrystalline diamond films and a broad peak at 1580cm-1 caused by sp2-bonded carbon at the grain boundaries [ 3 ].
Therefore, the dissociation of H2 and hydrocarbon are enhanced and the numbers of active radical are increased, so secondary nucleation rate is increased. sp2 sites in a-C:H have a tendency to gather into an intimate maxture of aromatic clusters and olefinic chains.
It leads to even more high secondary nucleation rate and fine grains.
The deposition conditions lead to more number of conjugated double bonds, which is reflected in their higher PL intensity.

Table 1 Chemical composition of typical samples of cold bending, % Heat number chemical composition, % C Si Mn P S Ceq 3-9101118A 0.22 0.56 1.38 0.017 0.012 0.46 2-0200091A 0.21 0.64 1.4 0.024 0.028 0.43 2-0101317A 0.19 0.57 1.34 0.031 0.026 0.43 GB1499.2-2007 ≤0.25 ≤0.8 ≤1.60 ≤0.045 ≤0.045 ≤0.52 Comparison of mechanical properties.
Tempered structure and other structures that effect the service performance are prohibited, and the grain size rating ≤9.
There were a large number of subsurface blowholes and internal cracks existing.
Crack was trend to initiate at ferrite–pearlite interface, ferrite-ferrite grain boundary, inside ferrite grain body, and at inclusion-matrix interface[5].

The grains are smaller than 0.25 mm (or 0.125 mm - limiting the grain size of cement).
However, a procedure of mixing (wetted) aggregate with cement and additions to achieve grain coating binder proved better.
With regard to the fact a large number of specimens were needed to be tested, fractions of prisms were used to determine the depth of penetration of water under pressure.
It is interesting that the results achieved do not exactly show whether the matter is a higher scurfing on standardized surface or on nonstandard surface (on the cut) during temperature cycles, because there were different values of scurfing depending on the number of temperature cycles achieved.

Thus, continuously crystallizing melt is under conditions close to those which are created by using grain technology.
N – total number of measurements, n – number of values of the structural component in a certain range of sizes.
With the increase in the ingot diameter the structure becomes less homogeneous and the grain size increases, with reduced strength characteristics and ductility increase (Table 1).
Diameter of an ingot, [mm] Pulling speed, [mm/s] σv, [MPa] δ,[%] Ψ,[%] HV, [kgf/mm2] 5 10 235,9 4,69 5,8 56,36 10 7 211,96 5,64 6,15 61,26 15 5 205,31 9,24 10,15 54,28 Conclusion The studies have shown that thanks to high cooling speeds and electromagnetic stirring, casting technology for aluminium alloys of small cross-section in a magnetic crystallizer ensures production of high-alloy aluminum alloys with even fine-grain structure and physical and mechanical properties that are equal to alloys obtained with granulation technologies.

Introduction During the recent ten years or so, a great number of expressways were built in China, and semi-rigid based asphalt pavement has been the main pavement structure in China for many years.
Methods of Test Specific gravity, Atterberg limits and Grain-size analyses were conducted in accordance with Chinese specification of transportation department.
Grain-size distribution of quarry samples Sieve Size(mm) Passing (%) 31.5 26.5 19 13.2 9.5 4.75 2.36 0.6 0.075 UG 100 98.6 83.5 50.6 12.0 0.7 0.5 0.3 0.3 RPCC 100 87.1 65.2 35.6 20.5 13.4 11.3 9.5 7.8 XLS 100 98.1 76.8 35.2 15.6 4.5 4.0 3.8 3.5 FLS 100 95.9 64.8 27.2 9.4 2.2 2.1 2.0 1.8 GMB 100 100 85-100 ---- 60-80 30-50 ---- 10-20 0-5 Sand 100 100 100 99.2 99.0 98.0 91.0 11.8 1.4 quarry or field samples specified as granular subbase meet all of the Chinese graded macadam upper-base(GMB) gradation requirements[1].
Grain-size distribution of field samples Sieve Size (mm) Passing (%) 31.5 26.5 19 13.2 9.5 4.75 2.36 0.6 0.075 DCLS 100 88.9 71.1 46.6 35.9 25.0 15.7 10.5 8.0 CTLS 100 100 85.3 70.4 60.1 34 14.6 10.4 4.1 RPCCRui 100 100 86.7 70 61.5 46.9 37.6 19.7 4.9 YWLS 100 96.1 74.2 48.1 36.9 33.4 27.3 16.4 9.1 RPCCXin 100 100 70.2 53.6 43.2 26.7 17.7 9 2.4 According to the Atterberg limits test, for the quarry and field samples, respectively.
To investigate the influence of increased compaction energy of (i.e. increased number of roller passes in the field) on density and hydraulic conductivity, falling head tests were conducted on field samples that were compacted to the minimum and maximum dry densities measured in situ.

The total output of grain, cottons, oil-bearing crops, fruits were 3060,000 metric tons, 80,000 metric tons, 405,000 metric tons and 865,000 metric tons.
The upward trend of growth has not only found in carbon emissions but also in carbon intensities.It’s 31.83 kilogram per mu in 2004, but the number turn out to be 37.64 kilogram per mu in 2009,the the growth rate of average annual link relative ratio was 3.49%.
The growth of carbon emissions has slow down between 2004 and 2007, average annual link relative ratio was ranging from 0.2% to 2.0%.Due to excessive burden on farmers, the three agricultural issues get further highlights,and the pressure of survival makes an increasing number of farmers rush into big cities to finding jobs instead of farming in rural areas.
Under the influence of the tide of wage earners, demanding of agricultural means of production have reduced, carbon emissions have reduced as a rusult.But at the same time, the overall grain output appears on a downward trend in Suzhou City.
So, Suzhou's agricultural production, especially grain production, was now facing enormous challenges.