INSTITUTE OF PULSE PROCESSES AND TECHNOLOGIES
NATIONAL ACADEMY OF SCIENCE OF UKRAINE
© 2012 Institute of Pulse Processes and Technologies of NAS of Ukraine. All rights reserved.
TECHNOLOGY OF ELECTROHYDROPULSE MELT TREATMENT
IN A LADLE AT A PREPOURING STAGE
THIS TECHNOLOGY PROVIDES FOR:
- melt degassing and removal of nonmetallic inclusions;
- increase of melt fluidity and filling capacity of molds;
- gas-shrinkage defects elimination;
- obtaining a favorable structure in a cast metal by impacting on its structural levels from atomic to a macrolevel;
- positive influence on cast metal properties.
ESSENCE
Pressure pulses of a wide frequency range (0.1 - 100,000 Hz) are supplied to the ladle with the melt by a special-purpose waveguide from the electrodischarge generator of elastic oscillations. This essentially accelerates heat-, mass-transfer, and physicochemical processes at the macro- and micro- levels rendering favorable conditions for its efficient crystallization.
ADVANTAGES
- environmental safety combined with successful treatment;
- very low electric energy consumption compared to other methods of ladle treatment: < 2 kW·h/t;
- short-time treatment: < 5 min;
- easy maintenance and high reliability of used high-voltage equipment;
- possibility of both independent and combined use of the method together with other technological techniques of ladle treatment (modifying, alloying, blowing, magnetohydrodynamical, etc.).
EFFICIENCY
- increasing the melt fluidity;
- free hydrogen removal, not less than 30 %;
- reduction of quantity of nonmetallic inclusions, by 15 %;
- refining of a macro- and microstructure;
- decrease of cold brittleness threshold by 20°С;
- decrease of spread of values of mechanical characteristics, not less than 15 % (castings from shipbuilding and general-purpose steels);
- increase of wear-resistance, not less than 50 % (castings from high-carbon alloys operated in conditions of hydroabrasive wear);
- decrease of magnetic conductivity in high-carbon alloys for electrotechnical purposes by 4-10 % ;
- increasing the air-tightness of irregular-shape castings from aluminum alloys operated in conditions of high pressures by 10%;
- decreasing a harmful effect of iron admixtures and structural heredity during remelting of secondary aluminum alloys.
IMPLEMENTATION
At shipbuilding and machine-building enterprises of Ukraine and the CIS for melt treatment in ladles with capacity up to 50 t. Equipment for 350 t ladles is developed.
Go to Next Page to read more about the technology of electrohydropulse treatment of liquid and crystallizing metals and alloys at a pre-pouring stage, and also about the Department developing this technology.
Справки по тел.: +38 (0512) 58-71-40, +38 (0512) 58-71-42
