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In addition, although a small number of samples were tested, the results for alloy C shows good repeatability.
In the current alloys, austenite is present both a blocky morphology located on prior austenite grain boundaries and as thin laths.
Since some hydrogen is expected at block interfaces on the prior austenite grain boundaries and at film austenite interfaces, it is perhaps not surprising that both intergranular and transgranular fracture paths were seen in most specimen fracture surfaces.

The specimen rotation allowed to increase the numbers of grains analyzed, limiting any texture effect.
Mean b grain size was 350 µm.

Mechanical properties of the sintered carbides are determined mainly by the densification and grain size in the sintered material.
Less grain growth of the NbC and ZrC particles was observed for samples with the 2.5% graphene addition.
Acknowledgements This study was carried out within the framework of GRAF-TECH programme, supporting scientific research on the unique graphene characteristics, funded by the Polish National Centre for Research and Development; the project: “Ceramic-graphene composites for cutting tools and devices parts with unique properties” – CERGRAF (project number: GRAF-TECH/NCBR/03/05/2012).

The increasing number of cars, especially those with Diesel engines, and trucks creates a constant threat to the environment.
The occurrence of characteristic high frequency "double arc" in the complex plane plot is usually attributed to granular structure and division between grain interior and grain boundary conduction [6].

In general, residual stresses in a ground surface are primarily generated due to three effects: thermal expansion and contraction during grinding; phase transformations due to high grinding temperature; plastic deformation caused by the abrasive grains of the wheel [1].
But, there is workpiece burn under ground condition of working procedure 3 at Vs=120m/s and variables angle α=0 0, β=0 0. 3D structure of working procedure 5 shows inferior result with cut depth increased as grain fracture and fall out, which is said strength of high/ultra-high speed grinding wheel was inferior than overseas.
residual compressive stress have better exhibition, which owe to friction decreased between workpiece and grinding wheel when α, β angle bigger and grinding wheel thick too thin. 1.169 1.170 1.171 1.172 1.173 1.174 1.175 1.176 0.0 0.1 0.2 0.3 0.4 d-spacing (Å) sin ² (Psi) 1.169 1.170 1.171 1.172 1.173 1.174 1.175 0.0 0.1 0.2 0.3 0.4 d-spacing (Å) sin ² (Psi) Working procedure 1 Working procedure 2 1.172 1.174 1.176 1.178 1.180 1.182 1.184 1.186 0.0 0.1 0.2 0.3 0.4 d-spacing (Å) sin ² (Psi) Phi .0 1.155 1.160 1.165 1.170 1.175 1.180 0.0 0.1 0.2 0.3 0.4 d-spacing (Å) sin ² (Psi) Working procedure 3 Working procedure 4 1.12 1.13 1.14 1.15 1.16 1.17 1.18 0.0 0.1 0.2 0.3 0.4 d-spacing (Å) sin ² (Psi) Working procedure 5 Fig.5 The relation of sin2 (ψ) and d-spacing of 5 specimens Residual stress [Mpa] Fig.6 Residual stress vs. working procedure number

The number of stable nuclei n is a function of temperature (T) following the equation:         kT G An exp (3) where A is a constant, GV is the critical free energy change, K is the Boltzmann constant.
Thus, at higher temperatures, we get few nanoparticles with larger grain size.
On the other hand, at lower temperatures, the nucleation rates are high and due to lower atomic mobility growth rates are low, which results in many small particles with smaller grain size.

Si feedstock of commercially available electronic-grade quality (grain size ~ 10 mm) was filled in a Si3N4 coated silica crucible with inner diameter and height of 60 mm and 100 mm, respectively.
Axial slice of the same crystal revealing the typical grain structure of mc-Si (c).
The roman numbers denote the process steps: I - Heating, II - Homogenization, III - Directional Solidification, IV - Cooling.

The main developments with these alloys are concerned with processing, to control the grain structure and properties, and to achieve nearer to net-shape products by non-chip making methods.
In the as-received conditions, the microstructure is composed of primary α-phase (equiaxed grains) and secondary α-phase (platelets) with a very little amount of β phase.
Due to the strain and strain rate gradients, strain, strain rate and stress are derived at the surface of the specimen with the help of equations ( 1 ) and the Fields and Backofen [2] relation ( 2 ), which assumes isothermal test and isotropic material. 2 3 = & & N r L π ε and 2 3 = N r L π ε ( 1 ) ( )3 3 3 2 m n R σ π = Γ + +% % with ln ln N m N ∂ Γ = ∂ % & ln ln N n N ∂ Γ = ∂ & % ( 2 ) where r is the specimen radius, L the length, m% and n% the torque sensitivities to the velocity of rotation and to the number of revolutions, respectively.

Table 1 The cutting forces and the tool life Experiment number Cutting parameter Cutting forces Tool life Dept of cut ap(mm) Feed rate f(mm/rev) Cutting speed Vc(m/min) Fx (N) Fy (N) Fz (N) Time (min) 1 0.2 0.10 50 63 105 82 40 2 0.2 0.15 60 29 112 121 33 3 0.2 0.20 70 25 142 155 27 4 0.3 0.10 60 54 108 110 30 5 0.3 0.15 70 79 171 137 20 6 0.3 0.20 50 20 110 225 23 7 0.4 0.10 70 35 113 120 29 8 0.4 0.15 50 57 172 165 25 9 0.4 0.20 60 107 220 235 14 Results and discussion Results of orthogonal cutting tests are first presented in terms of cutting forces and wear patterns.
The carbide grains and the cobalt binder of the insert are worn at the same rate.
Chipping may appear when friction force pull out the WC grains from the tool surface.

The raw materials comprised the 52.5 ordinary silicate cement, polycarboxylate-type high-performance water-reducer with reduction from 15% to 25%, machine-made sand and class-800 shale ceramisite for the aggregate of SFRLAC, natural sand and crushed stone with 20mm maximum grain size for the aggregate of ordinary concrete. the performances of shale ceramisite are shown in Table 1.
Table 1 Physical and mechanical perfomances of shale ceramisite Grain size (mm) ratio Bulk density (kg/m3) Apparent density (kg/m3) 1h absorption (%) Mud content (%) Tube-compressive strength (MPa) 5-10/10-16/16-20 4.5/3.3/2.2 788.7 1333 6.47 1.3 3.15 Table 2 Basic information of specimens No.
For B5, B3 and B6 slabs, before failure with the increasing load, deflection tended linearly increased, cracks on bottom surfaces widened with more and more numbers, the failure took place gradually with the increasing load.