The particle size of inoculant should not be too coarse or too fine. If the particles are too coarse, they cannot be dissolved and absorbed by molten iron quickly. The residual insoluble inoculant particles mixed into the casting will deteriorate the performance or lead to scrap. The particle size should not be too fine. The powder inoculant is very easy to oxidize and burn, lose the inoculation effect, and will cause slag inclusion in castings. For the ferrosilicon inoculant containing 75% Si, 0.5T molten iron is treated by the flushing method. When the temperature of molten iron is 1390 ~ 1450 ℃, the particle size of the inoculant should be 1 ~ 3mm. If the amount of molten iron is small or the temperature is low, or the instantaneous inoculation method is used, the particle size should be 0.2 ~ 2mm.
