Ferro silicon 75 is produced from coke, steel chips and quartz at 1500–1800 °C so silicon dissolves into molten iron. Buyers use it to kill oxygen in the ladle and to add silicon to structural, spring, bearing, heat-resistant and electrical steels.
HSALLOY supplies ferro silicon in the 75 / 72 / 70 / 65 grades listed on this page. Silicon combines readily with oxygen to form SiO2; the reaction also releases heat, which helps hold melt temperature while the steel is deoxidized. The same alloy is used as a reducing agent in ferroalloy shops and as an inoculant / nodularizing aid in cast iron, where it limits carbide and supports graphite precipitation.
Specification
| grade | Si min | Al max | S max | P max | C max |
|---|---|---|---|---|---|
| FeSi75 | 75.0 | 1.50 | 0.02 | 0.04 | 0.20 |
| FeSi72 | 72.0 | 1.50 | 0.02 | 0.04 | 0.20 |
| FeSi70 | 70.0 | 2.0 | 0.02 | 0.04 | 0.20 |
| FeSi65 | 65.0 | 2.0 | 0.02 | 0.04 | 0.20 |
Chemical composition (%) as published on the source product page. Standard referenced on the company knowledge page: GB/T 2272-2009 (ISO 5445:1980, MOD), used for steelmaking and casting deoxidation / alloying and for the magnesium-metal industry.
Where it is used
- Precipitation and diffusion deoxidation in steelmaking
- Alloying additive for low-alloy structural steel, spring steel, bearing steel, heat-resistant steel and electrical silicon steel
- Reducing agent for low-carbon ferroalloy production (high-Si grades carry low carbon)
- Inoculant and spheroidizing aid in gray and ductile iron — limits carbide and promotes graphite
Process notes
- Strong affinity of silicon for oxygen; SiO2 formation also adds heat to the melt
- High-silicon grades are used as a reductant because carbon in those grades is already low
- In cast iron, a measured addition helps graphite precipitation and spheroidization
Questions buyers ask
Which grades are listed?
FeSi75, FeSi72, FeSi70 and FeSi65, with the Si / Al / S / P / C limits in the table above.
What size and packing are offered?
Lump sizes 10–50 mm, 50–100 mm, 50–150 mm and 1–5 mm, packed in 1 MT big bags.
What standard applies?
The company knowledge page cites GB/T 2272-2009 for ferro silicon used as a deoxidizer or alloying agent in steelmaking and casting.
