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And this could effectively reduce the number of the grid, and improve the computing speed and the convergence precision.
Figure 3 Isotherm distribution Based on the reasonable simplified model, the residual decreases along with the increase of the number of the iterations, and the convergence quickly tend to stable, as shown in the Figure 4.
Figure 4 The change of the residual along with the number of the iteration Conclusion The temperature distribution around the borehole was obtained by simplifying and modeling the structure of the borehole, and the wellbore and wall rock were analyzed in the thermodynamics.
R., A mechanistic theory of ice lens formation in fine-grain soils.

Modification of Microstrucure and Residual Stress on Friction Welding Surface of Titanium Alloy by Water-jet Cavitation Peening Dongying Ju1,a, Xinmao Fu2,b, Shun Na 2,c, Bing Han3,d and Xiaohu Deng4,e 1Department of Mechanical Engineering, Saitama Institute of Technology, Fukaya, Saitama, 369-0293, Japan 2Graduate School of Engineering Department, Saitama Institute of Technology, Fukaya, Saitama, 3Department of Materials and Process, University of Science and Technology LiaoNing,185 Qianshan Zhong Road, Anshan, Liaoning, China 4Advanced Science Research Laboratory, Saitama Institute of Technology, Fukaya, Saitama, adyju@sit.ac.jp Keywords: Cavitation peening, Residual stress, Fatigue strength, Surface treatment, Grains, Dislocation.
Because of friction welding, grain refinement occurred at the friction-welded joints of titanium alloys, resulting in the weld hardness larger than that of the base metal.
When plastic deformation occurred, deformation twinning was induced at the dislocation block because of the small number of slip systems.

The microstructure of the base and machined composite was examined by scanning electron (SEM) microscopy.The specimens for micro-structural analysis were prepared by mounting on bakelite, polished using different grades of emery paper and diamond paste and finally etched with 0.5% hydrofluoric Acid. for clearer grain image of micro-structure.
(a-b) As machined condition WC-Co samples Table 1 WEDM Samples under different Pulse on Time and Delay Times Pulse on time (m sec) Pulse delay time (m sec) SEM Micrograph Remarks 4 10 Short off times has caused more number of sparks.
Poor heat transfer has given rise to hills of larger size and defects such as craters and voids 6 10 Higher pulse on time and low off times have caused an increase in the number of sparks and poorly machined surface.
With short off times more number of sparks per unit of time is obtained and thus more material removal.
Paulo Davim, “Optimization of electrical discharge machining characteristics of WC/Co composites using non-dominated sorting genetic algorithm (NSGA-II)”, The International Journal of Advanced Manufacturing Technology, Volume 36, Numbers 11-12, 1124-1132, DOI: 10.1007/s00170-006-0921-8 [11] Bozdana, A.

In mild steels, the grain boundary carbide particles are the potential sites for the initiation of fine microscopic cracks.
Experiments by Lindley and co-workers [4] and Gurland [5] have shown that the number of microscopic cracks initiated at the carbide particles increases with an increase in plastic strain.
However, the newly formed microscopic cracks cannot propagate in polycrystalline metals unless sufficient energy exists to break the atomic bonds, to drive the crack across grain boundaries and to perform plastic work.
Model Calibration and Predictions Faleskog, et al. [8] tested a large number of SE(B) specimens of a modified A508 steel at three different temperatures, -30, 25 and 55ºC.
These are computed using )4.0/()3.0( +−= NiPi , where i denotes the rank number and N represents the total number of fracture tests.

Table 1 Phosphorus content of five different Ni-P alloy platings Serial number of specimens 1# 2# 3# 4# 5# Phosphorus Content of the platings(%) 8.94 10.55 12.16 13.13 16.13 Table 2 Hardness of Ni-P alloy platings with different phosphorus content under different experimental condition Serial number Hardness of platings ( HV ) Heat temperature ( Celsius degree ) Heat time ( h ) 1# 2# 3# 4# 5# 1 552 677 580 623 584 200 2.0 2 600 810 720 655 655 250 3.5 3 740 930 946 1010 1100 300 5.0 4 950 1050 1150 1100 1150 350 1.5 5 1020 1100 1090 1250 1310 400 3.0 6 946 960 1010 1120 1150 450 4.5 7 930 946 908 986 1150 500 1.0 8 894 870 713 891 927 550 2.5 9 840 812 623 857 795 600 4.0 Results and discussions Mathematical model is established according to law of metal phase transition and shown as expression (1): (1) Type: - Microhardness of the plating ( HV ); - Aging temperature (Celsius degree ); - Aging time ( h ); - Regression coeffcient
Table 3 Regression equations about hardness of Ni-P plate with different phosphorous content Serial number of specimens Regression equation 1# 2# 3# 4# 5# After five regression equations in Table 3 were optimized and analysed, the optimal heat treatment technological parameters which maximizes the hardness value of the platings and expectant index of hardness are shown in Table 4.
Table 4 Expected target of the plating hardness and optimal parameters of the regression equations Serial number of specimens Optimal parameters ( Celsius degree ) expectant index of hardness( HV ) Measured value(HV) 1# T=414.6℃ (t=1.0h) 1010±81.6 1044 2# T=414.4℃ (t=1.0h) 1040±95.8 1058 3# T=399.2℃ (t=1.0h) 1070±133 1115 4# T=423.6℃ (t=1.0h) 1140±188 1148 5# T=420.0℃ (t=1.0h) 1230±178 1195 Table 3 and Table 4 reveal that hardness of the Ni-P plating heated treatment depend mainly on heating temperature in the heating time of 1-5h under the experimental condition.
When heat temperature is under 400-430 Celsium degree, precipitation of Ni3P phase will be insufficient, but when heat temperature exceed 400-430 Celsium degree, grain size of Ni3P phase will grow excessively, which will bring about abating.
Even if little change of the grain size cannot affect greatly hardness of the plating than that of the heating temperature because of small correlation between hardness of the plating and heating time.

Crushed powder can be effective in reducing the number of wire process.
For improving the tool life, increase production, reduce the number of tool change is beneficial.
Fine-grained powder processing needs of the cooling process.
Large amount of grain processing water is conducive to processing efficiency.
To make reasonable arrangements for a variety of powder particles the number of processing machinery.

Compared to traditional wood materials used in construction (chipboard, fiberboard, plywood), CBPB has a number of advantages: it is non-flammable, non-toxic, bio-and weather-resistant.
The wood filler has a number of unique properties: low density, good wet ability, ease of processing [3, 4].
The alkaline treatment removes wood hemicelluloses and lignin and increases the number of hydroxyl groups on the cellulose surface.
Conclusions The basis for producing of high-quality CPBP is a strong bond of wood chips with cement, but carbohydrates and tannins which are included in the content of timber when mixed with cement under the influence of the molecular cohesion forces are guided around the cement grains, forming the thinnest coating - adsorption layer.
Thus the formed layer hinders access of water to the grains of cement and discharges the products of hydration from them, leading to inhibition of the hydrolysis and hydration of the cement, and at certain concentrations of carbohydrate - to their stop.

The prior β-grain boundary as well as the heat affected zone banding are showing a coarsened α-plate boundary spacing [17].
Figure 2: Placement, orientation and number of tensile specimens Micro Computer Tomography.
A columnar grain structure is present in the welded samples shown in Figure 7.
It is evident in Figure 7 that specimens placed perpendicular to buildup direction (XY, XZ) have a reduced effective prior β-grain size.
The “BIAS ID” numbers are part of the figures and allow the retraceability of the results with respect to the mandatory documentation required by the funding organization.

Observations with a digital light optical microscope showed for example one desert sand with finely grained particles adhering on the surface of the sand grains.
These finely grained particles absorb the accelerator and disturb the polymerization.
For that reason only a limited number of test methods could be carried out with desert sand.
PC with granite crushed sand as filler shows a decrease of strength properties due to a reduction of fine-grained components.
The reason for the high loss of mass is that the immersion led to a detaching of sand grains from the surface.

At the moment, the columnar crystal disappeared completely, the grain size of samples was completely fine, the grain microstructure was very dense to occupy the whole sample, especially the grain of the arced end zone was the densest.
In the spiral end of chilling area, equiaxed grains are fine and close.
Therefore, a large number of crystal shards accumulates where columnar crystal disappeared, limiting the crystal growing completely and becoming a dense equiaxed grains zone.
Along the central flowing direction, the columnar crystal organization decreases gradually and slowly, the arrangement of columnar crystals is very neat, and the structure between crystals are the uniform and fine grains.
The fine grains occupy the center and to run through the whole sample