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This technology is based on the quenching solidification casting method.
Its essence is that a casting, except an initial rim, solidifies directly in a quenching bath.
It makes it possible to increase essentially the crystallization rate of silicon crystals,
to change their laminated morphology to the compact one. At the beginning of the process,
the casting's initial rim with the thickness of 5-8 mm is formed in a water-cooled metal mold.
Then a billet is extracted and placed in the quenching bath, i.e. it solidifies out of the mold.
Then a new portion of melt is poured in the mould and the next casting is formed.
That is why this technology is in the cyclic nature with high output of the casting process.
It is determined only by a time of filling the mould up and duration of forming the billet's initial rim in it.
This casting method is easy respondent to mechanization and automation.
The experimental casting machine and equipment for development of the silumin
production technology using are the now under design.
Technical characteristics
| Billet diameter, mm |
40-150 |
| casting productivity, t/h |
0,5-2 |
| Dispersion of primary silicon, mcm |
5-30 |
| Dispersion of eutectic silicon, mcm |
0,4-1,5 |
| Preservation of inhereted microstructure at remelting, hour |
not less than 2,5 |
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Microstructure of the AlSi18Cu1.5 casting with a diameter of 45 mm, x3000
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2 Microstructure of the AlSi18Cu1.5 casting with a diameter of 45 mm after normalization at 500°C for 4 hours, x2000
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Advantages
This technology allows production of higher-dispersivity castings from silumins without application of ecologically harmful modifiers,
provides obtaining of cast billets with nanostructure eutectic silicon.
Application fields
The method can be used for:
- casting of silumins with nanostructutre euectic silicon;
- production of wrought cast alloys;
- casting of antifriction alloys with high mechanical, wear resistant and exploitation properties;
- serious improvement of structure heredity of silumin billets and increase of their mechanical properties.
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