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Studies show that coated carbides offer significant advantages, thus a number of them were used to increase wear rates [2, 3].
Table 1 Tool material compositions Hardness (HRa) Minimum transverse strength (T.R.S) (MPa) Porosity Magnetic Saturation (cm / gram) Magnetic coercivity (KA/m) 91.5~92.8 2750 < A02 B00 C00 120~145 19.0~25.0 Table 2 WC-Co tool material properties Cobalt wt% Other Composition 8~12% Grain Growth inhibitors: ≤ 0.6% VC or Cr3C2 Contaminates: Ni < 0.03%, Fe < 0.03%, no trace of TiC or TaC allowed Cutting tool material.

Since it was demonstrated [5] that the time for the globulizing the silicon grains takes few minutes, the idea was to dramatically reduce the solution time, with the advantage of energy saving, more profitable use of furnaces and equipments, together with lower risk of distortions, in other words, significant reduction of treatment costs.
The letter (A or B) refers to the different cycle, while the number (1, 2, 3) describes the different ageing treatment.

With the solidification going on, the congregated quantity of TiC particles increased continually, leading to a large number of TiC particles being accumulated in liquid phases in front of solidification interface.
Strength enhancement of composites is concerned with the TiC particles dispersion distribution and grain refinement.

Aspherical surface vertex R 47.699 Spherical surface R -375.44 Korenich K 2.8393 A -1.9358E-06 B -1.8913E-08 C 4.3546E-11 D -6.2859E-14 Lens diameter(mm) 40 Lens thickness(mm) 9 Focal point distance (mm) 80 Lens material Acryl PMMA (Acrypet VH001, MITSUBISHI RAYON) Refractive index 1.49 Abbe's number 58 Figure 1.
References [1] M.Saeki, T.Kuriyagawa, K.Syoji, Machining of Aspherical Molding Dies Utilizig parallel Grinding Method, Journal of the Japan Society of Grinding Engineers (JAPE),68(8),(2002),1067-1071 [2] H.Ohmri, Electrolytic in-process dressing (ELID) grinding for optical parts manufacturing, International Progress in Precision Engineering IPES 7(1993)134-148 [3] H.Ohmri, T.Nakagawa, Analysis of mirror surface generation of hard and brittle materials by ELID (Electrolytic in-process dressing) grinding with superfine grain metallic bond wheels,Annals of the CIRP 44(1)(1997)261-264 05 10 15 20 25 30 35 40 60 300 600 900 cooling time (sec) shape error PV(μm) 0 5 10 15 20 25 30 35 40 125 140 155 170 holding pressure (MPa) shape error PV (μm) Figure 9 Relation between holding pressure and shape error PV Figure 8.

i, j, k express the node number of x, y, z axis respectively, adopting central difference method to deal with Control equations: 2 2 2 2 2 2 2 2 2 [ ] ( 1, , ) [ ] ( 1, , ) ( , 1, ) ( , 1, ) ( ) 2 ( ) 2 ( ) ( ) 2 2 2 ( , , 1) ( , , 1) [ ] ( , , ) 0 ( ) ( ) ( ) ( ) ( ) v v T i j k T i j k T i j k T i j k x x x x y y T i j k T i j k T i i k z z x y z α α α α α α α α α + + + − − + + + − ∆ ∆ ∆ ∆ ∆ ∆ + + + − − + + = ∆ ∆ ∆ ∆ ∆ (2) The melting latent heat △m is converted as the hoist of melting temperature (critical temperature).
So along the welding direction the laser power is greater, the heat affected area is greater, the cooling rate is slower, it is disadvantageous to control the heat-affected zone grain growth.

After deformation in elevated temperature a smaller number of twins are observed and, moreover, the process of dynamic recrystallization begins to microstructure (Fig. 4b).
Elongated grains free from twins can be observed.

Establishing of Random Aggregate Model Assuming that the shape of aggregate is spherical particle, according to 3D Fuller gradation curve obtained in the conditions of optimal close-grained aggregate [9], the expression formula of gradation curve as follow in Eq.(1)
The probability distribution curve can be obtained by the formula (2), accordingly, the aggregate number of various particle size can be obtained.

The grain peaks particles of a-C:B film became low and dense and therefore surface roughness decreased gradually from 0.532 nm to 0.75 nm.
The improvement of conversion efficiency might be attributed from the successful boron incorporation with carbon network, which therefore increases the number of holes and as a result increases the current density of the a-C:B film.

The decreasing effect of polymer’s grains between soil particles and it expands and contracts with absorption and desorption of moisture and makes soil particles close to each other and with establishment of aggregate, causes stability of soil structure and increase of soil porosity that will decrease bulk density [7].
After four weeks, hydrogel film surface becomes more irregular, roughness, number and size of voids increased.

Enhanced properties of RPC are obtained though grain size optimization, incorporation of micro-silica and post-set heat-treating.
Table 2 Experimental results Specimen number Yielding displacement (mm) Yielding force (kN) Ultimate displacement (mm) Maximum force (kN) Ductility factor Energy dissipation (kN.mm) COL1 18.5 146.6 74.2 152.8 4.0 3.8×105 COL2 18.8 130.1 89.6 140.1 4.8 5.3×105 Fig. 2 Hysteretic loops of COL1 Fig. 3 Hysteretic loops of COL2 Effect of Amount of Transverse Reinforcement.