Ferro Alloys / FeSi
Ferro Silicon
The most commonly used deoxidant and alloying element in steel and cast iron production.
Technical Specifications
Key Features
- High silicon content (72-78% Si)
- Strong deoxidant
- Low carbon ratio (1% max)
- Wide grain size options
- Economical and effective
Applications
- Steel deoxidation
- Cast iron graphitization
- Silicon steel production
- Electrical steel manufacturing
- Spring steel production
Dimension Table
| Element | Min. | Max. | Typical |
|---|---|---|---|
| Si | 72 | 78 | 75 |
| C | 0 | 1.0 | 0.5 |
| Al | 0 | 2.0 | 1.0 |
| P | 0 | 0.04 | 0.03 |
| S | 0 | 0.02 | 0.01 |
| Fe | - | - | Balance |
Technical Notes
- 01Fine grains for inoculation, coarse grains for deoxidation.
- 02Requires enclosed storage due to moisture absorption risk.
- 03Dosage amount determined by steel grade.
- 04Recommended to add after oxygen blowing.
What are ferroalloys?
Ferroalloys are master alloys of iron with a high share of an alloying element (Si, Mn, Cr, Mo, V...): e.g. FeSi75 (72–80% Si), high-carbon FeMn (75–80% Mn), FeCr. They are added to the melt in steelworks and foundries for deoxidation, alloying and inoculation. Using a ferroalloy instead of the pure element is cheaper and dissolves more readily in the melt.
Main ferroalloys and their roles
FeSi (ferrosilicon): the workhorse deoxidizer and Si source in steel; the 75% grade is standard and is also the base of foundry inoculants. FeMn (ferromanganese): deoxidation, sulphur fixing as MnS and Mn alloying; available in high/medium/low-carbon grades. FeCr (ferrochrome): the Cr source for stainless and alloy steels. FeSiMg (ferrosilicon magnesium): nodularizes graphite in ductile iron. Sizing (lump/granule) and addition point (furnace/ladle/cored wire) determine recovery; chemistry is verified by certificate.
Frequently Asked Questions
What is ferrosilicon used for?+
Deoxidation and silicon alloying in steel, and as the base of foundry inoculants. The standard grade is FeSi75 (72–80% Si).
What is ferromanganese used for?+
Deoxidation, fixing sulphur as MnS and manganese alloying. It comes in high-, medium- and low-carbon grades.
Why add a ferroalloy instead of the pure element?+
Lower cost, lower melting point and faster, more efficient dissolution in the melt.
What is FeSiMg (ferrosilicon magnesium)?+
A magnesium-carrying ferroalloy that converts graphite to spheroidal form (nodularizing) in ductile-iron production.
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