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The abrasives used for all lapping experiments were synthetic monocrystalline diamonds of 140/170 mesh size which constitute a distribution of grains sizes from 75 to 125 μm with an average of 100 μm.
This set of experiments involved changing the PDC layout as shown in Figure 5 and number of PDC samples run on a specimen holder.
Test numbers D3-D5 do not show data for inner and outer ring PDCs because of their 1 ring design.
Test number D7, which lapped 42 samples, resulted in an extremely high MRR variation.
That is, the vehicle diamond concentration and vehicle delivery rate were adjusted proportionally with the number of PDC samples.

The test method determines a rebound number of hardened concrete using a spring-driven steel hammer.
Two replicate cores shall be taken from at least six locations with different rebound numbers.
Tables relating the rebound number with mortar strength, indicate that low rebound number (equal to 15) can be related to a mortar strength as low as 1.4 MPa (a high rebound number of 34 corresponding to 25 MPa): this low limit is sometimes still too high for historic mortar strength values.
At the same time, the hole diameter has to be sufficiently large compared to the maximum sand grain size.
Vaults numbering starts from cathedral apses.

Here the powders are not fully melted and the increased temperature on the grain surface is responsible for the fusion of powders [6].
These processes can bring about desired improvements in porosity levels, precipitate phases, grain size, grain orientation and mechanical properties [69].
The ST time should be brief enough to limit grain growth and at the same time long enough to dissolve the unwanted precipitates.
High layer resolution although produces a better surface finish, the greater number of layers required to achieve the desired geometry are responsible for a significant increase in the product lead time.
High layer resolution can provide better surface finish but the build time increases due to the necessity of greater number of layers required to achieve the desired geometry.

Detailed secondary electron microscopy (SEM) performed on the longitudinal cross sections of the worn alloys indicates that the subsurface deformed layer beneath the worn surfaces is composed of a number of distinct layers like the mechanically mixed layer (MML), the shear deformed and bulk layers with increased hardness as the surface was approached.
Considering that the displacement was a direct result of shear deformation, the equivalent plastic strain, ε was calculated from the shear angle between grain boundaries and the normal to the worn surface, θ [2,4,5,11]; θ ε tan 3 3 = (1) by assuming that the shear deformation is parallel to the surface (refer to Figure 2).
The deformed structures consist of rotated and elongated primary grains towards the sliding direction.

The compaction pressure influences the number and size of the pores.
The characteristics of the powders DESIGNATION: C Carbon black from natural gas DESIGNATION: Fe Iron Powder DESIGNATION: Co Cobalt Powder DESIGNATION: W Tungsten Powder Technical Index Technical requirement Technical Index Technical requirement Technical Index Technical requirement Technical Index Technical requirement Humidity ℅ ≤ 0.5 Purety (%) ≥ 98 Iron Fe (%) ≤ 0.30 Iron Fe (%) Av grain ≤ 0.1 Ash content ℅ ≤ 0.1 Oxygen O2 % ≤ 0.6 Carbone C % ≤ 2.50 Oxygen O2 % ≤ 0.25 Volatile substance ℅ ≤ 1.5 Apparent density g/cm3 0.7 Oxygen O2 % ≤ 0.50 Chloride residue (%) ≤ 0.13 Results and Discussion In iron alloys, since the iron particle generally has a spherical shape with a regular microstructure of the grain boundaries, as the diffusion in these spherical particles has a higher activation energy than non-spherical particles.

The grain size was about 10 micons.
The colony count numbers were not reduced by the stainless steel surface compared to the number of colonies observed from the bacterial solution.
The original grain structure is magnified in (a1) and (b1) and (b2).
The SS316L grain size is about 10 microns and the SS304 has an average grain size of about 35 microns.
The original grain size is no longer visible in 13(c) and 13(d).

These results suggest that RHA promoted the formation of new products filling the pore space of the composite, changing the clayey material in a nature of a continuum, while the BSS promoted a substantial aggregation of the particles, wherein the soil reinforcement transformed clay in a particulate material coarser grain size.
There comes a binding effect, due to the increase in the number of contacts between the soil particles, and the strengthening of preexisting contacts.
Joint-analysis of the effects listed above suggests a substantial aggregation of the particles, wherein the reinforcement transformed the clayey soil into a particulate material of coarser grain size.

The microstructure of resultant specimens were characterized by measuring grain sizes of primary austenite and its solid fraction, using an optical microscope equipped with a digital image analyzer.
For this reason, the aspect ration was higher, but solid fraction was smaller because of smaller number of nuclei when compared to those at 10 deg.

In recent years, many researchers at home and abroad make a number of experiments and theoretical analysis on structural performance of steel fiber reinforced shotconcrete[1-6].Among them, Professor Du Guoping researches the enhancement mechanism of steel fiber reinforced shotconcrete from the viewpoint of its mechanical property [7] ; Professor Liu Xin carried out experimental study of basic mechanical properties of steel fiber reinforced shotconcrete from the viewpoint of this actual work [8]; But the research about the influence on concrete micro pore structure under different construction technology is still small.
In this paper, we do experiments on pore structure of steel fiber reinforced shotconcrete , use mercury intrusion method to test pore structure ,analyse and compare effect on concrete matrix pore structure with sprayed build and model build , and then from the microscopic point of view, analyze the effect on the mechanical properties and durability of steel fiber reinforced concrete under thus different construction technology. 2 raw materials and test methods. 2.1 raw materials Steel fibers used as shear waving steel fibers, produced by Chongqing Yizhu Trading Company , slenderness ratio is 60, tensile strength is greater than 500 MPa; Huaxin cement 42.5R ordinary portland cement is used to meet the requirements; coarse aggregate used machine processed gravel at the scene of the tunnel,for the Crossing site mechanism gravel, grain diameter is 6.0 ~ 10.8 mm continuous grading ; fine aggregate used compound with machine processed gravel and Yichang middle-thick river sand at the scene
Admixtures used highly active alkali-free liquid accelerating agent and highly active water reducing agent produced by Germany BASF corporation; ganister sand uesd silica fume produced in Chongqing, the average grain diameter is 0.1 microns; mixing water used on-site drinking water. 2.2 test method The commonly used gaging pore methods are of optical microscopy, electron microscopy, mercury intrusion method, adsorption methods, X-ray small angle diffraction method and so on.
Based on the pore distribution curve of mercury intrusion test, is the quantitative characterized form between pore diameter of steel fiber reinforced concrete and pore size, number.The curve is a cumulative distribution curve, can visually and quantitatively show the composition and distribution of pores, as Figure 2.Table 4 in which the critical pore size is defined as the amount of mercury pressed into the corresponding significant increases of steel fiber reinforced concrete maximum pore size; most probable pore size refers to the corresponding peak value of pore size.

Test condition of wear resistance are as follows: the abrasive grains are 40 purpose, the most-positive pressure is 23kg, the standard speed is 240r/min, testing time is 5 min, the size of the sample is 10mm×20mm×60mm .
Table 2 Heat treatment processes Serial number Heat treatment processes Process one Process two Process three Process four Diffusion annealing+880℃×2h×oil quenching+180℃×2h×air cooling Diffusion annealing+880℃×2h×oil quenching+220℃×2h×air cooling Diffusion annealing+880℃×2h×oil quenching+260℃×2h×air cooling Diffusion annealing+880℃×2h×oil quenching+500℃×2h×air cooling Results and Analysis Microstructure and Hardness at Cast and Diffusion Annealing States.
Without any indication of brittle flake or the form of loose sediments of multiple carbide and WC ceramic phase,there is a large number of parallel cutting grooves, and the grooves orientation are identical basically, no present the transverse or oblique furrows, showing that the surface hardness is large under the process, wear sands cannot transverse or oblique cutting, wear-resisting performance is better.
The wear resistance is higher with tempering sorbite + WC grains dues to the evenly distributed carbide particles between the short ferrite lath bundle skeleton matrix in the tempered sorbite, The fatigue crack is not only hampered by ferrite phase interface when extending from surface layer to the surface during wear process, but also occurs plastic deformation, which makes the crack tip stress relaxation and inhibits the extension [15].