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Both nodulizers and inoculants have many different composition blending ratios and size distributions. Foundry factories may select different nodulizers and inoculants, depending on different conditions, such as production equipment, liquid iron components and casting products of their own. ZFA have had years-long experience in production of nodulizers and inoculants. Combining with long-run export service and technical exchange with foreign and domestic experts, we have been in the capacity to contribute various casting additive alloy products meeting demands from international and domestic customers.
The following is a general introduction to selection for nodulizers and inoculants, while specific specifications need to be detailed further by casting customers depending on their own practical cases, or customers may contact our Export Department

1.Selection for Nodulizers:
(1) Nodulizers containing 4%, 5%, 5.5% magnesium belong to low magnesium nodulizers, RE falls between 1%-2%, commonly used to nodulize with medium frequency furnace melting. Their chemical reactions are smooth and steady, nodular elements is easy to be absorbed. However, it is required that the sulphur should be lower.
(2) Nodulizers containing 6%, 7% magnesium belong to medium magnesium series nodulizers, commonly used in medium frequency furnace melting and electric furnace double reheating melting or medium frequency furnace melting pearlite ductile iron castings. Based on casting wall thickness and sulphur content in base iron, proper nodulizer adding quantity is determined, applicable range is wide and nodulizing process technology is broad.
(3) High magnesium series nodulizers are suited for cupola melting liquid iron with sulphur content of 0.06%-0.09%, and additive quantity is between 1.6%-2.0%.
(4) Low Al nodulizers are used for castings that liable to produce subsurface porosity defect and castings that specify requirement for Al content in liquid iron.
(5) Liquid iron processed by pure Ce and pure La-produced nodulizers are pure with less inclusions and round graphite nodules. Pure Y-produced nodulizers are suited for large cross-section castings, lagging nodulization deterioration and preventing blocky graphites. Nodulizers containing Sb are used for pearlite ductile iron.
(6) Low Si nodulizers are suited for foundry to use quantity of return material; and Ni-Mg nodulizers are used for high Ni austenitic ductile iron.

2.Selection for Inoculants
(1) Si, Ba, Ca and Al alloys are used widely, inoculation effect is very ideal and consumption is less. Ba is a very active element, Si-Ba inoculants with low Ca-Ba content have strong grpahitizing ability, so are the first selection for gray cast iron, ductile iron and vermicular cast iron castings. Medium and high Ba inoculants are suited for castings that require quantity of ferrite.
(2) The high grade die-oxidation inoculants is very effective to deduct oxidation,and it will increase the Si content to reduce the production cost.It will be used to prevent the gas porosity and subsurface porosity.
(3) Si-Sr inoculants do not increase eutectic cells in gray cast iron, but have good graphitizing effect, and are far more effective to prevent thin wall cast chill, so as to avoid thin wall casting (cylinders, cylinder heads) leak; used in ductile iron inoculation, to increase graphite nodules and prevent blowholes in piston ring castings.
(4) High Al low Ca Fe-Si inoculants are used for low sulphur gray cast iron inoculation,It’s very valid for the elimination of chill. Fe-Si inoculants containing Bi make up for shortage that singly additive Bi generates insignificant effect. Si-Zr inoculants can refine austenite dendrites and increase cast iron strength, commonly used double reheating melting process. Inoculants with Mn additive can decrease complex alloy melting points, easily diffuse and be absorbed in liquid iron. Especially, in such aspect, Si-Ca-Ba-Mn inoculants have outstanding effect.
(5) Rare Earth inoculants have special effect on decrease of chill cast iron brittleness. For high brand hypoeutectic gray cast iron, they can obviously improve graphite shapes. Without need to sedulously decrease carbon content, cast iron strength can also be improved, so as to improve machining performance.
(6) In-Mould inoculants is the best resource-economic and inoculation-effective process mode, casting system is installed with ceramic foam filter, both form a combination to produce high quality castings.In-mould inoculants will be increasingly favored by foundry enterprises.
(7) The specially produced covering, The content is pure and size distribution is reasonable, It’s helpful to produce the stable and high quality cast iron.

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