Calcium Silicon Alloy (short name CaSi) is multi-element composite ferroalloy. It combines calcium, silicon, iron as core active components, widely used in LF secondary refining, continuous casting clean steel and cored wire production.

Different from single ferrosilicon deoxidizer only with deoxidation function, CaSi integrates deep deoxidation, efficient desulfurization and alumina inclusion denaturation three core functions. Calcium has stronger affinity for O and Al₂O₃, converts hard blocky alumina into low-melting spherical calcium aluminate, thoroughly solves tundish nozzle blockage pain point of high-end clean steel. Our factory supplies Ca31Si60 / Ca28Si60 / Ca24Si60 / Ca20Si55 / Ca16Si55 full grades, lump for ladle adding and fine powder for cored wire filling.

Silicon content

The main component of calcium silicon alloy is silicon, and the content is generally between 60% and 70%. Its role in steelmaking is to eliminate iron oxide, reduce melting point, and increase hardness and strength.

Calcium content

The calcium content in calcium silicon alloy is generally between 10% and 30%. The increase of calcium can improve the plasticity and toughness of steel. Adding an appropriate amount of calcium can improve the processing properties of steel and reduce the hardness of steel.

Aluminum content

The aluminum content in calcium silicon alloy is generally between 1% and 2%. The main role of aluminum is to increase the strength and corrosion resistance of steel. In addition, it can promote the reduction reaction of calcium and improve the reduction efficiency of calcium silicon alloy.

Manganese content

The manganese content in calcium silicon alloy is generally between 1% and 2%. The role of manganese is to increase the hardness and strength of steel, promote the dissolution of carbon in steel, and reduce the precipitation temperature of steel.

chemical composition

Brand	Chemical Composition %
	Ca	Si	C	Al	P	S
	≥	≥	≤
Ca31Si60	31	55-65	1.0	2.4	0.04	0.06
Ca28Si60	28	55-65	1.0	2.4	0.04	0.06
Ca24Si60	24	55-65	1.0	2.5	0.04	0.04
Ca20Si55	20	50-60	1.0	2.5	0.04	0.04
Ca16Si55	16	50-60	1.0	2.5	0.04	0.04

FAQ

LF Ladle Refining Clean Steel (Largest Demand)

Ca31Si60/Ca28Si60 high-calcium grades for bearing steel, automotive deep drawing IF steel, oil & gas X60/X80 pipeline steel, effectively control internal inclusions.

Cored Wire Spheroidizing/Calcium Treatment Raw Material

0–3mm ultra-fine CaSi powder as filling core wire material, realize precise deep ladle calcium treatment for automatic continuous casting lines.

Mass Construction Carbon Steel

Ca20Si55/Ca16Si55 low-cost grades for rebar, wire rod ladle auxiliary deoxidation, balance production cost and steel quality.

Ductile Iron Foundry Production

Small dosage CaSi added before tapping as composite inoculant, eliminate thin-wall casting white chill edge defects.

Medium & High Strength Alloy Steel

Match ferromanganese/ferrochrome to adjust molten steel silicon & calcium index, improve finished steel impact toughness.

Industrial Application Scenarios

Q1: What is the essential difference between CaSi and conventional FeSi deoxidizer?

A: Ordinary FeSi only provides silicon deoxidation; CaSi has calcium component that can denature alumina inclusions and deeply remove sulfur, exclusive for continuous casting clean steel.

Q2: What particle size to choose for ladle adding vs cored wire production?

A: Ladle refining: 10–50mm large lumps; automatic cored wire filling: 0–3mm fine CaSi powder.

Q3: Standard addition dosage of CaSi in LF ladle refining?

A: 1.2–2.2 kg CaSi per ton molten steel; increase 0.1~0.3kg if raw molten steel sulfur exceeds 0.06%.

Q4: Can we provide test samples? What's lead time & MOQ?

A: Free 1–5kg test samples available. Standard in-stock goods:7–15 working days; customized high-calcium grades:20–30 working days, MOQ 25 tons full container, T/T & L/C payment supported.

Deoxidizer Calcium Silicon Alloy In Steelmaking