spheroidizing agent for casting
The selection of spheroidizing agent should pay attention to the following items:
1. Magnesium content of 4%, 5%, 5.5% belongs to low-magnesium spheroidizing agent, and RE is between 1% and 2%. It is mostly used for smelting in intermediate frequency furnace and spheroidizing of low-sulfur molten iron. It has the advantages of gentle spheroidization reaction and easy absorption of spheroidizing elements.
2. The magnesium content of 6% and 7% belong to the medium magnesium series spheroidizing agent, which is mostly used for double smelting in cupola and electric furnace, or smelting pearlite cast ductile iron castings in intermediate frequency furnace. According to the casting wall thickness and the sulfur content of the original molten iron, determine the appropriate amount of spheroidizing agent, which has a wide range of applications and a wide range of spheroidizing treatment processes.
3. High-magnesium spheroidizing agent, suitable for cupola smelting, molten iron with sulfur content of 0.06%-0.09%, and the addition amount is between 1.6%-2.0%.
4. Low-aluminum spheroidizing agent is used for castings that are prone to subcutaneous pore defects, and castings that require aluminum content in molten iron.
5. The spheroidizing agent produced by pure Ce and pure La has less pure inclusions and round graphite balls after spheroidizing treatment. The spheroidizing agent produced by yttrium-based heavy rare earth is suitable for large-section castings, delaying the spheroidization recession and preventing massive graphite. Sb-containing spheroidizing agent is used for pearlite nodular cast iron.