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At the same time, the treated FeNi30 powder was compared with the original FeNi30 powder (Numbered Exp.2) in the experiment.
First,-200 mesh FeNi30 catalyst powder was mixed after being corroded (Numbered Exp.1) with -200 mesh lepidosome graphite homogenously.
It forms high melting point solid inclusion which can prevent carbon from delivering into the grain and diffuse.

As shown in Fig.2, the spectrum of N-H bond moves toward the lower wave number direction from (a) to (d) with the increasing of the DP.
For linear precursors we synthesized during these experiments, higher DP means more N-H bonds, and the more N-H bonds, or the higher the DP, the lower the wave number of N-H bond in FT-IR spectra.
However, none of them shows crystals or grain boundaries, this means the ceramics we synthesized were amorphous materials.

This study conducted a number of tensile tests of a cast TiAl alloy with directional lamellar microstructure to statistically examine the strength retention and ductility undulation.
In principle, those mis-oriented lamellar colonies are transformed from the equiaxed a grains that precipitate during final solidification due to not yet well optimized heat radiation condition.
Acknowledgements This study was financially supported by National Basic Research Program of China (973 Program contract number 2011CB605503) sponsored by the Ministry of Science and Technology of China.

The Brinell hardness number is a function of the test force divided by the curved surface area of the indent.
Nucleation occurs at a relatively high temperature (often just below the solubility limit) so that the kinetic barrier of surface energy can be more easily overcome and the maximum number of precipitate particles can be formed [4].
During the ageing period, some of the alloy compounds precipitate and end up at the grain boundaries to increase material strength by interfering with the slip planes.

Table 1 The size attribute, Material properties and boundary conditions parameter numerical value diameter 740mm leaf number 3 boss ratio 0.2 Experiments using reverse engineering technology to obtain the 3-d model of propeller and Pro/E software have been painting of flow unit model.
The wireframe is shown in Fig.1.At the grain roof caving in order to establish the space rectangular coordinate system origin of coordinates, XY plane parallel to the propeller circular cross section, the flow direction is the Z axis positive direction.
Its kinetic energy and dissipation rate transport equation are: （1） （2） Among them, is caused by turbulent kinetic energy of the average velocity gradient, is caused by turbulent kinetic energy of the buoyancy，is compressible turbulent flow pulsation expansion effects on total dissipation rate, , , , , are empirical constants, , are the turbulent kinetic energy and the turbulent dissipation rate corresponding to the prandtl number.

The reason for the change of growth direction was explained from the point of view of the relation between the plastic zone size and the grain size [5].
From the results mentioned above, texture and environmental effect have important roles in the transition of fracture mechanism. �� �� �� �� �� �� 5 �� �� Fig.1 Shape and dimensions of specimen (a) Ultrasonic fatigue specimen (b) Rotating bending fatigue specimen 10 3 10 4 10 5 10 6 10 7 10 8 10 9 100 150 200 250 300 350 � Stress amplitude, σσσσa (MPa) Number of cycles to failure, Nf (cycles) U (Plain specimen) R.B (Plain specimen) U (Drilled specimen) R.B (Drilled specimen) Fig.2 S-N curves of plain specimen in ambient air 0.0 5.0x10 5 1.0x10 6 1.5x10 6 2.0x10 6 0.01 0.1 1 10 U (260MPa) R.B (260MPa) U (225MPa) R.B (225MPa) : Change of crack growth direction � Crack length , llll mm Number of cycles , N (cylces) Fig.3� Crack growth curves in

Introduction Dense ceramics with optimized properties are required for a number of applications.
The spray pyrolysis is a powerful technique for the synthesis of complex oxides with submicrometer grain size and homogeneous shape [4].
This technique has been currently used to synthesize a number of ceramic compositions [6-9].

Generally, the grinding force directly affects the machined surface roughness, the specific grinding energy and the wear of the abrasive grains.
During grinding, the arc length along the contact zone is longer, that is, the normal and tangential force are increased with the force increased of the individual abrasive particles as well as the increasing number of abrasive particles involved in cutting process.
Nd is the approximate active cutting point density, which can be obtained by calculating the number of abrasive particles that have the significant wear platforms per unit area [7].

As billets are in strong 3D compressive stress state during the extrusion process, the original recrystallized structures in soft state or casting structures are destroyed, lead to a large number of dislocation slip belts which can eliminate the defects generated in the casting.
The material hardening after deformation presents obviously, grain refinement, compact structure and deformation texture appear prominent.
The speed of the top die is 20mm/s.The part is extruded at room temperature (20℃), the step length is 0.5mm, the total number of steps is 60, and the stroke of the top die is 30mm.

In AFM, the grinding media, with viscoelasticity, flexibility and cutting is to contain grains, is in the squeeze flow under pressure to form a semi-solid, flowing, "extrusion block".
The hydraulic system contains a number of advantages meeting the experimental requirements, as follows: First, the hydraulic system can provide comparatively bigger power.
Then the units of finite element are 94538 and the number of nodes is 177639.