Ferro Alloys / FeSiMg
Ferro Silicon Magnesium
Primary alloy used as nodularizer in ductile iron production.
Technical Specifications
Key Features
- Controlled magnesium content (5-7% Mg)
- Rare earth element addition
- High nodularization efficiency
- Low MgO slag formation
- Stable reaction characteristics
Applications
- Ductile iron (spheroidal graphite iron) production
- Compacted graphite iron
- Automotive parts manufacturing
- Pipe and valve manufacturing
- Wind turbine components
Dimension Table
| Element | Min. | Max. | Typical |
|---|---|---|---|
| Mg | 5.0 | 7.0 | 6.0 |
| Si | 44 | 48 | 46 |
| RE | 0.5 | 1.0 | 0.8 |
| Ca | 0.5 | 2.0 | 1.0 |
| Al | 0 | 1.0 | 0.5 |
| Fe | - | - | Balance |
Technical Notes
- 01Grain size selection should be based on ladle method.
- 02Minimize exposure to air.
- 03Treatment temperature should be between 1450-1520°C.
- 04Magnesium recovery rate is between 40-60%.
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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