The inoculation treatment helps eliminate chill and promotes graphite formation. It also improves the mechanical properties of the castings. Elkem offers an extensive range of premium inoculants, supplied globally and our specialists will help you select the best one for your application.
The proprietary CAT inoculant tablet contains multiple times the nucleation elements present in a regular foundry-grade FeSi75 inoculant. This means the oxy-sulfide forming elements react faster to promote solidification and nucleation.
Inoculants are ferroglobe products that are added into the liquid iron to provoke and certify the matrix structure of the cast metal. A well-selected inoculant helps eliminate chill, brings carbon out as graphite and increases the strength of the castings.
Elkem offers a comprehensive range of premium inoculants, supplied globally. The specialist team will help you choose the right one for your foundry process.
The inoculant is deposited into the melt either in the furnace, ladle or in-stream. It improves the nucleation of the iron and allows for a more uniform distribution of nodules, reduces the tendency for white mouth and favors the formation of graphite rather than cementite (iron carbide). Inoculants also minimize undercooling below the metastable eutectic temperature which can cause metallurgical shrinkage. This is particularly important in electrical furnaces and pneumatic insulated pouring ladles.
Inoculation is the process of introducing a foreign material into the liquid cast iron to initiate nucleation and control the matrix structure of the final casting. Several inoculant options are available from ASK Chemicals Metallurgy, including barium-containing inoculants that are effective in ferritic ductile iron castings.
Using Sphere-o-Dox (SOD) as an inoculant enhancer can produce significant improvements in microstructural and mechanical properties of pearlitic ductile iron castings. An example of a successful application is the use of SOD to eliminate carbides in thin-section, shell-molded castings produced by Foundry A, a medium-sized producer of a 65-45-12 ferritic ductile iron grade. Previously, carbides in the thin sections had been a frequent problem despite the use of standard inoculants and blends.
These inoculants are added to the liquid cast iron in various locations, including in the furnace, in the ladle, or in the stream or mold. The location of the inoculant addition determines the inoculant treatment and the final cast iron characteristics.
Inoculants are a group of chemical compounds which are added to liquid cast iron in order to promote the nucleation of graphite, and suppress carbide formation. Inoculants are available for a range of applications and can be added at several locations in the foundry process; in the furnace, ladle or in-stream.
Elkem Foundry Products has developed a new product line which is a sustainable alternative to traditional rare earth inoculants for gray and ductile irons. The Ultraseed Zr inoculant and the Preseed preconditioner are unique in that they are completely free of rare earth elements.
A high-nucleation inoculant can eliminate chill, reduce the number of carbides and improve machinability. In addition, the inoculant can be used to control the casting hardness and enhance graphite quality parameters. Sphere-o-Dox has replaced high-potency rare earth inoculants at numerous foundries, resulting in significant metal treatment cost savings. This is due to its oxy-sulfide enhancing additive. This blend of oxy-sulfide forming elements is known to produce a high volume of graphite promoting nuclei when added to molten grey or ductile irons.
Inoculants help avoid metallurgical defects such as carbides in cast iron by increasing the number of nucleation sites in the metal prior to solidification. They also minimize undercooling below the metastable eutectic temperature, promoting formation of graphite rather than cementite (iron carbide).
In many cases, standard oxygen- and sulfur-containing inoculants are used to replace high-potency rare earth-containing inoculants, but they don’t always perform as well. Sphere-o-Dox (SOD) has been shown to dramatically improve inoculation effectiveness, and its use at foundries has resulted in nodule count increases, increased ferrite and pearlite levels, and improved mechanical properties.
Elkem Foundry Products is showcasing two more sustainable alternatives to traditional inoculants, Ultraseed Zr and Preseed preconditioner, at the Metal+Metallurgy show in Shanghai March 13-16, 2019. Visit booth H16 to learn about their performance and benefits. For a complete program schedule, click here.
English
Write a Message