Registration Number
0217U004654,
0114U000203
, R & D reports
Title
Development of highly efficient ecological methods of modifying at precrystallization period for creation of resource-saving technologies of reception of ductile iron cast products with finely-crystalline structure and improved properties.
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Head
Bublikov Valentin B, Доктор технічних наук
Registration Date
22-02-2017
Organization
Physico-technological institute of metals and alloys National academy of Sciences of Ukraine
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Research goal - development of scientific and technological bases of high-performance methods of modifying influence on microheterogeneous state of iron-carbon melts in precrystallization period that extends possibilities of crystallization processes control in the direction of intensifying of graphite spherocrystalsformation, preventing the transition to a metastable crystallization mechanism, obtaining offine structure whichincrease the base for development of new cast alloys with high technological, physico-mechanical and special properties, and creation of ecological resource saving technologies of obtaining ductile cast iron castings with high reliability and durability for modern engineering. Methods of premodifying treatmentproviding the formation in the original Fe-C-Si melt of additional clusters of graphite (nanoareas with a high mass fraction of carbon), which increases the modifying efficiency in increasing by 1.2-1.4 times the number of active centers of spheroidal graphite crystallization are research. Methods and parameters of control of high-carbon melt modifying process in precrystallization periodare defined. It is established that optimization of ductile iron structure formation in thin walled castings is achieved by a combination of modifying treatment in precrystallization period with subsequent fixation of modifying effect in rapid crystallization. Minimizationof time between inoculation and solidification beginning in combination with the cooling rate of 15-10 °C/s, characteristic for 2-3 mm wall thickness of the casting, increases more than 5 times the amount of formed during solidification spheroidal graphite inclusions (up to 1400-2000 mm-2), prevents the transition to the metastable crystallization mechanism, provides the formation of fine austenite-graphite globular eutectic, increases in 2-3 times the amount of ferrite in the metal base, increases the plastic properties of the cast material in 1.5-2.0 times, increases its reliability and durability. Modifying in flow reactors ofgating systems proceeds without pyroeffect and release into the atmosphere of magnesium oxide and other harmful substances that radically improves working conditions of staff and the ecology of the environment. Savings from the introduction of the developed technology in the industry is achieved via reducing in 2.0-2.5 times of modifying alloyscharge, the elimination of the operation of thermal processing (energy consumption per 1 t of castings will be reduced to 350-400 kW/h), increasing of casting yield from 45-50 % to 60-65 %, improving of machinability in 1,3-1,5 times, increasing of metal utilization rate in 1.5-5.0 times, reducing parts weight by 20-30 %, improvingof mechanical properties and service life of ductile iron parts.
Product Description
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Бачинський Юрій Дмитрович
Берчук Дмитро Миколайович
Дорошенко ВолодимирСтепанович
Зелена Людмила Опанасівна
Медвідь Сергій Миколайович
Моісеєва НаталіяПетрівна
Нестерук Олена Петрівна
Овсянников Володимир Олександрович
Пряжнікова Наталія Василіївна
Ясинська Олена Олександрівна
Ясинський Олександр Олександрович
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2020-04-02
