Method for improving precipitation rate of graphite in molten iron

• Main Authors: CHEN WANFU, ZENG HUI, YUAN YUHAO, LUAN JIYI, DONG HUI, WANG NIANXIN, LI CHANGXIN, ZHANG GE, TIAN CHAO, DONG HONGZHUANG, MA XINGYUN
• Format: Patent
• Language: Chinese; English
• Published: 21.10.2022
• Subjects: CHEMISTRY; COMPOUNDS THEREOF; INORGANIC CHEMISTRY; MANUFACTURE OF IRON OR STEEL; METALLURGY; METALLURGY OF IRON; NON-METALLIC ELEMENTS; PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OFWROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS

The invention discloses a method for increasing the precipitation rate of graphite in molten iron. The method comprises the following steps: increasing the carbon content in the molten iron; increasing the temperature of molten iron; the silicon content in molten iron is increased; the sulfur content in molten iron is reduced; intense stirring is performed; the cooling speed is proper; and the higher oxygen content ensures that molten iron is in full contact with oxygen. The carbon content of the molten iron is greater than or equal to 4.63%; the molten iron temperature T is not less than 1430 DEG C; the silicon content of the molten iron is greater than or equal to 0.45%; the sulfur content of the molten iron is less than 0.020%; a stirring head is adopted for stirring, and the rotating speed of the stirring head is larger than or equal to 100 r/min to improve stirring kinetic energy; and the temperature reduction speed is controlled to be 0.5-1.0 DEG C/min when the molten iron is cooled. On the premise of e