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The addition of grinding aid do little harm to the activity of steel slag, and the mechanical strength values when used in cement and concrete was improved.
Since there are many factors affecting the effect of grinding aids, more details of its application should be studied in greater depth in the future.
Because of complex composition ,volatile property and poor wear resistance, the application and theory on steel slag grinding aid is less than that on blast-furnace slag grinding aid in China.

Introduction High nitrogen steel has good toughness, uniform corrosion resistance, local corrosion resistance [1-3] and excellent mechanical property [4].
Temperature is one of the important factor for the reaction process rate, whose increase can enhance the reaction rate and diffusion coefficient.
Compared with other factors, the increase of the temperature has little effect on the increaseing of the nitrogen content in steel.
Although the temperature on the nitrogen content in steel is not significant affected, but it is the important kinetic and thermodynamic parameter in smelting process and should make further experiment and research[10].
Analysis of high nitrogen steels refining factors with high pressure and bottom-blowing nitrogen.

Introduction For modelling a process chain to predict the final material properties, it is necessary to use microstructural physics based models, since microstructure is the state variable of materials properties.
The final goal was to predict microstructure evolution and resulting properties of Aluminum sheet.
For Aluminum sheet the crystallographic texture was identified as microstructural key issue governing the resulting sheet properties.
The mechanical properties of the final sheet were tested in uniaxial tension tests on specimens cut along different directions within the rolling plane, and by cup drawing.
On the other hand, also other parameters like friction and elastic properties seem to be equally important for the exact cup height prediction.

Introduction Controlled non-homogeneity of the structure by powder metallurgy processes makes it possible to obtain special properties of materials, which cannot be obtained by conventional technologies [1].
In particular the porosity is beneficial to the sliding bearings, which decides their mechanical properties to a greater extent than any other microstructural factor (grain size, dislocation nature, texture) [4].
Isolated porosity controls the formation of different types of fracture facets related to geometry and properties of particle necks.
Zakharova, Mechanical properties of sintered materials.
Upadhyaya, Densification, microstructure and properties of supersolidus liquid phase sintered 6711Al-SiC metal matrix composites, Sci Sinter, 42 (2011) 363

Scheme of application of mechanical load to the steel beam and fastening conditions.
The magnitude of the distributed load is taken by the load factor m = 0.2.
Using the mathematical apparatus and mathematical descriptions of the properties of materials described in [1], the time of influence of the standard temperature of the fire is calculated, at which the flame retardant mineral wool cladding detaches from the beam. 3.
Using the mathematical apparatus and mathematical descriptions of the properties of the materials contained in [1], the limit of fire resistance is calculated, as shown in fig. 3.
To do this, in the future a system of correction factors should be developed to reduce the value of the limit of fire resistance due to the sudden destruction of fire protection systems.

Long term performance of nickel base superalloy components under cyclic thermo-mechanical loading depends on the resistance to crack initiation and propagation.
Successful description of crack propagation in nickel base superalloys requires the ability to predict fatigue crack growth rates (FCGRs) and trajectories under complex non-proportional thermo-mechanical loading.
Constitutive behavior of damageable materials must reflect the fact that degradation of material properties is never confined to a single point, but in fact is 'smeared out' over a certain neighborhood.
Dwell effects: oxidation and creep Crack growth rates under the conditions of thermo-mechanical fatigue, particularly in the presence of tensile dwells, are strongly affected by creep and oxidation.
When the use of maximum stress intensity factor maxK and its cyclic range K∆ can still be justified, these two parameters offer a sound basis for incorporating spectrum loading and dwell effects into reliable predictive models of fatigue crack growth.

The model corresponds to Fig. 1 and includes mechanical and thermal parts.
Thermophysical properties are given in Table. 1.
Thermophysical properties d [mm] H [mm] с [kJ/(m·K)] ρ [kg/m3] λ [Vt/(m·K)] Powder medium 14.42 0.03 134.0 19.3·103 173.0 Steel plunger 14.42 10 0.31 8.88·103 70.0 Ceramic walls 40 40 8.0 1.8·103 0.26 Firstly, initial height of filling is assorted, finally reaching the height of h = 3.42 mm.
In the results described above, factor k in the kinetic law for porosity was taken as constant, and temperature did not affect porosity evolution.
In the consequent work, we should take into account the two-dimensional behavior of the flow, because real kinetics of porosity evolution and properties of the mixture change with temperature.

It was affected by tensile strength therefore local effect has not found spalling in crater field.
Characterization porous such as volume, size, spacing and pore size distribution is primary factor to influence material properties of FC mainly on density and strength.
Experimental 3.1 Material Properties In this investigation pre-foaming method were applied to develop target specimens.
Conclusion Mechanical anchoring occurs when the PF and concrete matrix interlocking.
Ashby, Cellular Solids Structure and Properties, Cambridge University Press, (1997), in press

Two-diameter piston push centrifuge is suitable to refined cotton dewatering as refined cotton and nitrocotton have similar properties, namely, they belong to fiber, and need continuous dewatering and washing.
It’s because refined cotton has such properties as wonderful hydrophilicity, good absorption [4], light slurry concentration and short fiber, etc.
Slurry concentration is a vital factor, which concerns whether piston push centrifuge can work properly and its production capacity.
Screen is the important component of piston push centrifuge, affects centrifuge separation effect and operability directly.
[5] Zhang Di, in: Selection and Manual of Mechanical Separation, Machinery Industry Press (1998), p. 207, In Chinese

By means of “micro-peak and soft/hard plane” contact model given in the present work, physical definition and influence factors of tC1and tC2 were discussed in detailed.
By means of the simplified contact model of micro-peak and soft/hard plane presented in the following section, the influence factors of two inflexions are demonstrated in detailed, and then some principles of optimized designation for the complicated triblogical system are given to make soft layer on the hard substrate more economical and longevous.
Obviously, the value of Hm is related to not only the mechanical properties of soft layer, the coarseness of friction parts but also the thickness of the soft layer.
(8) As shown in Eq.(7), the values of tC2 are determined by the applied load, the surface morphologies of the mutual friction parts, and the mechanical characteristic of soft layer.
By means of “micro-peak and soft/hard plane” contact model, those are pointed out that the value of tC1 chiefly depend on surface morphology of substrate and counterpart, whereas the value of tC2 is also affected by the applied load and layer characteristic.