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Experimental Investigations on Surface Residual Stresses in the As-sprayed and Ground Nanostructured WC/12Co Coatings Zhaohui Deng1,a, Zhongwei Hu1,b, Qi Jing 1 and Yadong Gong2 1 National Engineering Research Center for High Efficiency Grinding, Hunan University Changsha, China, 410082 2 School of Mechanical Engineering & Automation, Northeastern University, Shenyang, China,110004 a edeng0080@vip.sina.com; bhuzhongwei2003@yahoo.com.cn Key words: Nanostructured WC/12Co coatings, Surface grinding, residual stresses, Experimental Investigation Abstract: In this study, a number of experiments on surface grinding of nanostructured WC/12Co (n-WC/12Co) coatings were conducted on a precision surface grinding machine with a horizontal axis and rectangular worktable.
Table 1 The properties of n-WC/12Co coating Powder grain size [nm] Density [g/cm 3 ] Fracture toughness [MPa.m 1/2 ] Vickers hardness [GPa] Elastic modulus [GPa] Poisson's ratio 30.00~50.00 14.50 5.50 13.50 405.00 0.30 ` Fig.1 SEM observations of the as-sprayed n-WC/12Co coating The X-ray diffraction method is the most popular one for directly measuring residual stresses.

The average grain size was about 320 meshes and about 45 μm.
In other words, the number of nodes in the input layer is set 6.
In other words, the number of nodes in the selected hidden layer is 11.
Parameter setting for genetic optimization is introduced as follows: the population size, maximum number of generations, number of bits of variables, crossing probability, mutation probability and generation gap were set 40, 20, 10, 0.7, 0.01 and 0.95, respectively.
The initial population number, maximum number of generations, crossing probability and mutation probability of the genetic algorithm were set 20, 80, 0.4 and 0.2, respectively.

Fig.1: Schematic illustration of the constructional stages in biomineralization according to Mann [8]: (1) supramolecular preorganization, (2) interfacial recognition at initial mineralization site, (3) vectorial regulation of shape and size of product and (4) biomineral tectonics Based on the insights into natural biomineralization processes, an increasing number of biomimetic or bio-inspired routes for material synthesis are proposed [8].
Since there are only a limited number of routes to ceramics at low temperatures [13], there are only few reports about the bio-inspired synthesis of such materials [14], especially in combination with polymer substrates [15].
With increasing number of surface-induced seeds they will soon meet neighboring deposits and further vertical growth is stopped.
No TiO2 deposition is observed on as-prepared microspheres, inorganic material is formed as spherical grains that were generated by homogeneous precipitation (Fig.3a).

(a) View of atomic configuration where coordinate numbers are indicated by color.
Figure 1(a) depicts the atomistic configuration with colors representing the coordinate number of each atom, and the radial distribution function is plotted in Fig. 1(b).
The numbers of atoms in the model are differentiated by their Voronoi polyhedron type in Table 1, where only those with more than 5% of the total atoms are shown.
In the situation of a crystal the dislocation can propagate until it disappears at a surface or it is stuck at an obstacle like a grain boundary.

It was observed, in all cases, significant changes of the disc bainitic microstructure, i.e: martensitic transformation and a drastic grain-size reduction, on a depth of 4-6 mm.
The thermal responses of the four pad-types are very different in terms of maximal temperatures, number of pins simultaneously in contact, as well as alternation between pins in contact (Fig. 3).
Thus, pad P4 presents the greatest alternation, the lowest number of pins in contact (2 to 4) and the highest maximal temperature.
On the contrary, pad P3 presents no alternation, the highest number of pins in contact (7) and the lowest maximal temperature.

The condition number DRR instrument analysis approach proposed by Smith was applied to determine instrument operating mode.[7] In the Mueller algebra, a DRR instrument can be described by (1) where I is the measured intensity or Stokes parameter of the output polarization state mathematically selected by , is the Mueller representation for a polarizer at angle with respect to the polarization axis of interest, is the Mueller representation for a waveplate with phase retardation, subscripts a and g refer to analyzer and generator elements, respectively, M is the sample of interest and S is the Stokes vector of the input light.
N is the number of independent measurements necessary to return a full Mueller matrix.
Smith’s condition number approach to W-Matrix analysis allows determination of both N and suitable angle-increment pairs for rotation of the linear retarders.
Draine, "The discrete-dipole approximation and its application to interstellar graphite grains," Astrophys.

Table 3 Levels and factors for orthogonal test level binder content molding pressure /N molding time /min 1 1/2 2500 10 2 1/3 3500 20 3 1/4 4500 30 3) Analysis of test results Table 4 Scheme of experiments to prepare fiberboard and analysis of results number binder content molding pressure/N molding time/min bulk density /kg/m3 1 1/2 2500 10 519 2 1/2 3500 20 583 3 1/2 4500 30 615 4 1/3 2500 20 451 5 1/3 3500 30 508 6 1/3 4500 10 516 7 1/4 2500 30 398 8 1/4 3500 10 468 9 1/4 4500 20 485 level 1 572 456 501 — level 2 491 519 506 — level 3 450 538 507 — Limit deviation 122 82 6 — It can be seen from Table 4, sodium silicate content is the most important influence for volume density of slag wool fiberboard, molding pressure follows and molding time of the minimum factor.
Increasing the volume weight and limit the gas phase in low levels are making fiber more close-grained and increase the compressive strength of fiberboard.
Table 5 Compression strength of different fiberboard number binder content/g volume weight /kg/m3 compressive strength /MPa 1 1000 653 0.36 2 500 570 0.31 3 250 475 0.28 3) The influence of sodium silicate binder to water absorbability It can be seen from Table 6: blast furnace slag wool fiberboard per unit volume water absorption is reduced by the increasing of the sodium silicate addition, but the volume water absorption is more than 50 percent that fails for satisfaction the water requirements.
Table 6 Results of fiberboard water absorbability number binder /g volume water absorption /% unit volume water absorption /kg/m3 1 1000 46.1 461 2 500 54.8 548 3 250 71.1 711 The waterproof performance is a major factor restricting fiberboard to use in external wall insulation.

Fig. 2 Ionic conductivity against weight percentage of Lithium Perchlorate Lithium Perchlorate is the main ion carrier in the electrolyte system thus adding it will increase the number of free mobile ions [4].These free mobile ions also increase the amorphous structure of the polymer through the favorable free volume as a result the ion migration takes place easily.
The phenomenon occurred due to a lot of free ions in the sample getting too close to each other and that increases the possibility of ion pairing, triplet or higher ion aggregation which reduce the total number of effective charge carriers and ion mobility [6].
The sphere represents the crystalline region where it consists of a number of platelets or lamellae radiating from a nucleating centre called spherulite [7, 8].
The nano sized filler interacted with the free ions where the alumina grains were found to be smaller in size and evenly distributed across the surface.

Table1 Rubber concrete mix Number Water kg/m3 Cement kg/m3 Sand kg/m3 Gravel kg/m3 Rubber Super plasticizer kg/m3 Species Proportion % Dosage kg/m3 CC1 158 405 624 1266 — 0 0 3.04 CRC2 158 405 562 1266 2-4mm 10 30.7 3.04 CRC3 158 405 499 1266 20 61.4 3.04 CRC4 158 405 562 1266 60-80mesh 10 21.86 3.04 CRC5 158 405 499 1266 20 43.72 3.04 CRC6 158 405 562 1266 2-4mm 10 30.7 3.04 CRC7 158 405 499 1266 20 61.4 3.04 CRC8 158 405 562 1266 60-80mesh 10 21.86 3.04 CRC9 158 405 499 1266 20 43.72 3.04 CRC10 158 405 562 1266 2-4mm 10 30.7 3.04 CRC11 158 405 499 1266 20 61.4 3.04 CRC12 158 405 562 1266 60-80mesh 10 21.86 3.04 CRC13 158 405 499 1266 20 43.72 3.04 CRC14 158 405 562 1266 2-4mm 10 30.7 3.04 CRC15 158 405 499 1266 20 61.4 3.04 CRC16 158 405 562 1266 60-80mesh 10 21.86 3.04 CRC17 158 405 499 1266 20 43.72 3.04 Test Method.This test has 17 design team, a total of 51 test block.
However, the surface of the rubber concrete block cracks obvious interruption phenomenon, and cracks than ordinary concrete cracks short, the numbers are more than ordinary concrete.
Table2 Rubber concrete test results Number Rubber slump (mm) compressive strength (MPa) Species Proportion (%) Dosage (kg/m3) CC1 — 0 0 30 51.55 CRC2 2-4mm 10 30.7 33 40.81 CRC3 20 61.4 38 35.87 CRC4 60-80mesh 10 21.86 27 38.72 CRC5 20 43.72 25 28.30 CRC6 2-4mm 10 30.7 36 42.12 CRC7 20 61.4 39 37.47 CRC8 60-80mesh 10 21.86 30 41.54 CRC9 20 43.72 29 29.08 CRC10 2-4mm 10 30.7 46 42.28 CRC11 20 61.4 53 39.70 CRC12 60-80mesh 10 21.86 41 39.17 CRC13 20 43.72 23 26.96 CRC14 2-4mm 10 30.7 30 43.58 CRC15 20 61.4 37 38.81 CRC16 60-80mesh 10 21.86 45 43.28 CRC17 20 43.72 34 34.27 Compressive strength.The compressive strength specimens of each group results in Table 2.
In contrast curve of intensity of each group, we can find that: (1) Rubber concrete strength after treatment was higher than no treatment rubber concrete, modification effect of CCl4 solution> NaOH solution> water; (2) When the rubber concrete coarse rubber particles increased, the strength and the modification effect are improved, but with the fine rubber particles increases, reducing the effectiveness of modification; (3) When the rubber pretreatment methods and the same dosage, crude rubber modified grain is better than fine rubber powder; (4) When the rubber content is 20%, the solution is treated with NaOH fine rubber powder concrete, strength decreased significantly than the untreated.

Introductions With the rapid development of the economic in our country, the scale of the infrastructure construction is being expanded constantly, and the pile foundation is used in a large number [1].
Because of the complexity of the pile foundation, a large number of manpower and material resources are in need of to get the actual measurement data.
A large number of scientific research achievements have been got by this means.
Zhang, With mud skin of coarse-grained soil and structure interface mechanics characteristic test research, Rock and Soil Mechanics, 9 (2005) 1374-1378.