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To evaluate the grain refining effect, both melt poured into the standard TP-1 mould.
In the case with A-EMS, the grain morphology becomes mainly rosettes with a mount of globular grains and the grain size was sharply decreased (Fig.2 b).
It demonstrated that A-EMS melt treatment has the efficiency to restrain grain growth up and change the grain morphology.
In general, addition of grain refiners (such as Al-Zr) in 7000 series alloy was found to be beneficial towards grain refinement.
The grain refinement mechanism of cast aluminium by zirconium.

Fully considering coke pyrogenation, coke combustion, water evaporation, gas turbulent and chemical behavior, this paper has been build turbulent mathematical model based on the grain orbit model.
Nu* is the Nusselt number.
The number of the particles each layer is about 1000 and their position in the layer are random.
A large number of BF operation proved the correctness of the inference.
The reason may be too small particles number in numerical simulation.

The mean misorientation within the austenite grain was 2.5°.
These grains are similar in size to the grain presented in Figure 2 (no prior deformation).
The R-F plots illustrating the orientation relationships between the austenite grain and the bainite laths in the two grains are displayed in Figures 3a and 3b.
Indeed, only eight variants are present in this grain.
The two K-S variants that are the closest to the measured lath orientation are also displayed and numbered following the Bishop and Hill notation [9].

As the alloy homogenized by 455°C/16h, except for needle-like phases inside grains, part of phases on grain boundaries had dissolved into the matrix and exhibited rounded shapes.
Except for eutectic phase on grain boundaries, a large number of needle-like phases in the matrix distribute along grain boundary.
The needle-like phases in the matrix almost dissolve into the matrix completely and only few of them next to grain boundaries remain.
In the as-cast microstrure, the area fraction of second phase on grain boundary possesses a proportion of 3.28%.
The as-cast alloy contained needlelike Al2CuLi and Al2Cu phase in the matrix and Cu-rich phase and Ag-containing phase on grain boundary.

Out of each production batch a certain number of patterns are randomly picked for testing dimensional accuracy.
At this stage all wax patterns are numbered and documented for total process tracking.
After quality inspection each cluster becomes a production number for documentation and tracking.
Figure 4: Control of incoming ceramic materials include grain size and distribution, chemical purity and grain geometry.
Very tight quality control of raw materials (purity, grain size, grain distribution and grain geometry) and slurries (liquid content, viscosity, pH and binder content) has to be applied to maintain quality and for process stability.

This can be caused by a number of circumstances including: the temperature of the injected melt being too low; the die temperature being too low (such as during process start-up or from excessive use of lubricant spray); the plunger velocity being too low or the melt flow path being too long or too narrow.
This 'pre-solidified' solid fraction is made up of dendritic grains that have nucleated within the melt as it encounters the relatively cooler surfaces of the ladle, launder and shot sleeve.
Such action will generate a large number of fine crystals (or dendrite fragments) suspended amidst the surviving dendrite cores (as observed by Li and coworkers), although this would not reduce the total solid fraction of the slurry.
The action of the MPC is also proposed to reduce the average size of the suspended dendritic grains and reduce the viscosity of the slurry prior to entering the gate [14].
Diminution of the larger pre-solidified dendritic grains and a general reduction in the average suspended grain size will allow an additional small period of time before the average grain size grows to the pre-MPC dimensions.

As the number of the steel production becomes larger, the kind of steel dealed by RH degasser more than before.
Experiment 1.1 Experimental materials  The raw materials used in the experiment are: Fused grain magnesia-chrome (3～1mm, 1～0mm, 0.061mm), Indian concentrate chrome ore(0.0178mm).
Table 1 chemical composition of the Fused grain magnesia-chrome (mass%) raw materials Al2O3 SiO2 Fe2O3 CaO MgO Cr2O3 14 Fused grain magnesia-chrome 3.88 0.72 5.40 0.97 72.54 16.43 20 Fused grain magnesia-chrome 4.96 0.48 7.76 0.62 65.78 20.34 Indian concentrate chrome ore 13.23 0.83 17.65 0.29 11.59 53.73 1.2 Sample preparation From the samples preparation we know that sample 1 only have fused grain magnesia-chrome sand. 2, 3, 4, 5, samples were added to 5%, 10%, 15%, 20% of India's chrome ore powder.
Between spinel and spinel, periclase and spinel, periclase and periclase produce a large number of holes between them, resulting in significantly lower compressive strength.
It can be seen that the organizational structure of the sample between Indian concentrate chrome ore sand and a large number of spinel formed the "bridge"[4].

But fine-grained mineral separation and conductivity from two or more similar mineral separation are more difficult.
Non-conductors slip plate type electric machine is mainly used for from a large number of products are separated in the conductor mineral.
Fine grained electricity separator is one of the important problems in the attention and research both at home and abroad.
The fine-grained electrostatic separation is still interesting and important subject of attention.
The Soviet Union, Canada, and Italy and other countries place more emphasis on the fine-grained electrostatic separation, and a lot of research, and it has published a number of papers.

A six number code was adopted to summarize the rolling condition: the first two define the roll asymmetry ratio (15 for R1/R2 =1.5), the third and fourth the PTR (in %) and the last two numbers the total thickness reduction (in %).
The grains at the upper layer are finer than at the bottom interface.
Figure 8a shows that at the central layer interface a region of finer grains is generated due to the interfacial friction.
Zhang, Shear deformation and grain refinement in pure Al by asymmetric rolling.
Skrotzki, Static recrystallization and grain growth of accumulative roll bonded aluminum laminates, J.

The casting, refining and electromagnetic process (CREM) can refine grains, decrease segregation, and improve the surface quality of the ingots [5, 6].
As a result, the less difference of the microstructures between the center and the edge of the ingot and the enlarged mushy region would be acquired, which would promote the grain refinement and the formation of equiaxed grains.
The nominal composition of the alloy is Al-4.3Cu-1.8Mg-0.6Mn (numbers indicate wt.%).
In conventional HDC condition, the grains are inhomogeneous and the grain size becomes coarse from the bottom to the top due to the unbalanced cooling.
In electromagnetic HDC condition,the microstructures are improved, and the difference of grain size between the top and bottom is reduced.