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Ferro Silicon Magnesium (FeSiMg)

Questions we are asked

Frequently asked questions

What is ferro silicon magnesium used for?

It is the nodulariser for ductile and SG iron production. The magnesium changes graphite from flakes to nodules, which is what gives ductile iron its strength and ductility.

What composition do you supply?

Typically around 44–48% silicon with magnesium, rare earth and calcium contents set to your requirement. The magnesium, rare earth and calcium levels are what determine the treatment behaviour, so they are specified per customer.

What magnesium content should I choose?

It depends on your treatment method and base iron sulphur level. Sandwich treatment generally uses higher magnesium than tundish cover or cored wire methods. Tell us your method, ladle size and base sulphur and we will advise.

Why does the alloy contain rare earth elements?

Cerium and lanthanum neutralise trace subversive elements such as lead, bismuth and antimony that would otherwise interfere with nodule formation, and they assist nucleation. The right level depends on the cleanliness of your charge.

Do I still need to inoculate after magnesium treatment?

Yes, and it is not optional. Magnesium treatment strips sulphur and oxygen, which are the very elements whose compounds provide nucleation sites. Treated iron is left poorly nucleated and prone to chill, so post-treatment inoculation is essential.

What sizing do you supply?

Sized to your treatment method — sandwich, tundish cover and cored wire each call for different fractions. Confirm your method when enquiring.

Have a question that is not answered here? Talk to our team — send your specification, tonnage and destination and we will come back with a quotation.

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