PRODUCTION SINCE 1958

One of the most important activity in the metallurgy of modern foundry, is the application of the inoculant process that consist in addition of small amounts of elements to liquid metal just before the casting.

This elements called inoculants, alloe to change and check the metal structure with important phisical and mechanical changes and the negligible variation of the beginning alloy chemical analysis.

INOCULANT PRIORITY:

• reduction of carbides (Fe₃C) and White solidification
• promote the graphite composition and shape
• reduction of the evanescence effect favoring the graphitic nucleation step.
• micro eddies reduction
• reduction of graphite floatation
• defects reduction of the gases
• superficial ferrite elimination

INOCULANTS ELEMENTS EFFECTS IN THE IRON-CARBON ALLOYS

Aluminium

.. improves the ferritization and neutralizes the azote.

Calcium

.. has the function of strong flux for the bath, improving the graphittic germination and reducing the carbides Fe₃C

Barium

.. favorites the graphite creation, reducing the inoculants evanescence in the alloys.

Strontium

.. reduces the white solidification, increasing eutectic cells, reducing the eddies defects caused by excessive graphittic germination.

In the spheroidale cast iron produced with ternary alloy Fe Si Mg with the absence of rare earth, has the function to reduce the white solidification and increase nodules (addition of pure strontium in the base inoculant Fe Si must be 1%)

Zirconium

.. neutrlizes free azote, better the inoculant solubility and associated with manganese, reduce the temperature of inoculant Liquidus.

Cerium and Rare Earth

.. have the function to increase the quantity of eutectic cells in the alloy and reduce the evanescence effects.

.. are also good desulphurizing, and inoculants with the base elements often are used as preconditioners of the bath.

Bismuth

.. added to rare earth in the spheroidal cast irons, increase the graphitic nucleation center, reducing the dimension and facilitating the reduction of white solidification.