Direct Conclusion: For standard steel deoxidation and silicon alloying, we quote FeSi75 specification with 72–78% Si, 10–50 mm lump size, fines ≤5% below 10 mm, and 1 mt jumbo bag packing. For cost-controlled carbon steel production, we quote FeSi72 grade with 70–73% Si. For foundry silicon adjustment, we quote FeSi65 grade with 63–68% Si.
Before quotation, we confirm six fixed items: ferrosilicon grade, Si range, FeSi impurity limits, ferrosilicon particle size, ferrosilicon MTC/COA documents, and export packing. Without these items, two ferrosilicon prices cannot be compared directly.
Experience Note: This ferrosilicon specifications guide is based on our quotation work, batch inspection, MTC review, COA checking, export packing and buyer specification confirmation for ferrosilicon for steelmaking and ferrosilicon for foundry use.
ZhenAn standard quotation values are listed below. For low-Al, low-Ca, different particle size, different packing or special steel grades, we issue a separate written specification before quotation.
Ferrosilicon Procurement Checkpoints
The following table shows our standard ferrosilicon quotation checkpoints. Each item must be confirmed before FeSi75, FeSi72 or FeSi65 price comparison.
| Check Item | ZhenAn Standard Quotation Value | Why We Check It |
|---|---|---|
| Main grade | FeSi75 / FeSi72 / FeSi65 | Determines silicon addition, recovery calculation and unit consumption |
| Si content | FeSi75: 72–78%; FeSi72: 70–73%; FeSi65: 63–68% | Affects addition rate, steel chemistry and delivered cost per effective Si unit |
| Standard size | 10–50 mm lump | Matches standard steel mill ladle, EAF and furnace addition |
| Fines tolerance | ≤5% below 10 mm | Controls feeding loss, dust generation and weight dispute risk |
| Packing | 1 mt jumbo bag | Supports export loading, warehouse storage and unloading operation |
| Documents | MTC / COA, packing list, commercial invoice, bill of lading | Used for batch approval, customs clearance and internal quality records |
1. Ferrosilicon Grade Specifications
Ferrosilicon specifications start with silicon content. We quote FeSi75, FeSi72 and FeSi65 as standard ferrosilicon grades. The table below gives the fixed grade range, standard size, standard packing and main application for each grade.
| Grade | Si Content | Standard Particle Size | Standard Packing | Main Application |
|---|---|---|---|---|
| FeSi75 | 72–78% | 10–50 mm | 1 mt jumbo bag | Ferrosilicon for steelmaking deoxidation and silicon alloying |
| FeSi72 | 70–73% | 10–50 mm | 1 mt jumbo bag | Carbon steel production with lower Si content than FeSi75 |
| FeSi65 | 63–68% | 10–50 mm | 1 mt jumbo bag | Ferrosilicon for foundry silicon adjustment and lower Si addition |
Buyer Note: Do not compare ferrosilicon price by grade name only. FeSi75 price comparison is valid only when Si range, FeSi impurity limits, particle size, fines tolerance, packing, MTC/COA and trade term are the same.
2. Ferrosilicon Chemical Composition and FeSi Impurity Limits
The following values are ZhenAn quotation specification ranges for FeSi75 supply. ASTM A100 and ISO 5445 are listed as standard references; the quotation and MTC/COA follow the written specification values below.
| Element | FeSi75 Standard Grade | FeSi75 Low-Al Grade | FeSi75 Low-Ca Grade | Why It Matters |
|---|---|---|---|---|
| Si | 72–78% | 72–78% | 72–78% | Main element for deoxidation and silicon addition |
| Al | ≤1.5% | ≤0.5% | ≤1.5% | High Al increases alumina inclusion risk in sensitive steel grades |
| Ca | ≤1.0% | ≤1.0% | ≤0.3% | Ca affects inclusion modification, slag reaction and deoxidation behavior |
| C | ≤0.15% | ≤0.10% | ≤0.15% | Controls carbon pickup in low-carbon steel |
| S | ≤0.025% | ≤0.020% | ≤0.025% | Controls sulfur-related hot workability risk |
| P | ≤0.04% | ≤0.03% | ≤0.04% | Controls brittleness risk in selected steel grades |
| Mn | ≤0.50% | ≤0.30% | ≤0.50% | Affects final alloy balance and heat calculation |
Purchase Contract Tip: If the order requires low-Al FeSi75, low-Ca FeSi75, low-C, low-S or low-P ferrosilicon, the exact limit must appear in the purchase contract and the ferrosilicon MTC or ferrosilicon COA.
3. Ferrosilicon Particle Size and Fines Tolerance
ZhenAn standard ferrosilicon particle size for steelmaking quotation is 10–50 mm lump. The default fines tolerance is ≤5% below 10 mm. Different particle size orders require a separate written size specification before quotation.
| Size Range | Quotation Status | Fines / Oversize Control | Application |
|---|---|---|---|
| 10–50 mm | ZhenAn standard quotation size | Fines ≤5% below 10 mm | Steel mill ladle, EAF and furnace addition |
| 3–10 mm | Separate written size specification | Fines and oversize limits written before quotation | Foundry ladle addition and inoculation-related use |
| 0–3 mm | Separate written size specification | Oversize limit written before quotation | Powder filling, controlled feeding and granular use |
| 10–100 mm | Separate written size specification | Fines and oversize limits written before quotation | Large furnace charging and bulk addition |
Ferrosilicon Particle Size Checklist Before Order
- Write the particle size range in the purchase order.
- Write the fines tolerance below the lower sieve size.
- Write the oversize tolerance above the upper sieve size.
- Request sieve analysis when the feeding system requires strict particle size control.
- Use 10–50 mm lump as the default ferrosilicon for steelmaking size.
4. Ferrosilicon Bulk Density for 10–50 mm Lump
The following ferrosilicon bulk density values are used for 10–50 mm lump quotation and container loading review. FeSi65 has a higher iron balance than FeSi75, so the bulk density and true density are higher.
| Grade | True Density | Bulk Density for 10–50 mm Lump | Container Loading Note |
|---|---|---|---|
| FeSi75 | 3.7 g/cm³ | 1.51–1.60 t/m³ | Standard 10–50 mm export lump grade in 1 mt jumbo bags |
| FeSi72 | 3.8 g/cm³ | 1.55–1.65 t/m³ | Used when the buyer accepts lower Si content than FeSi75 |
| FeSi65 | 4.3 g/cm³ | 1.78–1.90 t/m³ | Higher iron balance gives higher density than FeSi75 |
For container loading, we confirm bag weight, total net weight, pallet requirement, moisture protection and loading plan before shipment. Ferrosilicon bulk density affects container space calculation, unloading operation and warehouse storage planning.
5. Appearance and Surface Quality Check
Ferrosilicon lump should show a metallic silver-gray to dark gray surface. Visual inspection does not replace MTC/COA chemical analysis, but it helps detect moisture exposure, heavy oxidation, slag attachment and abnormal fracture condition before factory use.
| Visual Check Item | Accepted Condition | Rejected Risk Signal |
|---|---|---|
| Surface color | Silver-gray to dark gray metallic appearance | Wet surface, heavy oxidation or abnormal discoloration |
| Fracture surface | Uniform metallic fracture surface | Dark porous center, severe segregation or weak lump structure |
| Cleanliness | Limited slag or refractory attachment | Visible non-metallic contamination or excessive slag |
| Bag condition | Dry jumbo bag and clear shipping mark | Wet bag, broken bag, caking fines or unclear batch mark |
Inspection Tip: Check samples from different bags, not only the top layer. If the fracture surface, particle size or moisture condition is inconsistent, hold the batch for further checking before furnace use.
6. Ferrosilicon MTC, COA and Export Documents
Ferrosilicon MTC and ferrosilicon COA are quality documents for batch approval. Our standard export document package includes MTC/COA, packing list, commercial invoice and bill of lading.
| Document | Issued By | What It Shows |
|---|---|---|
| MTC / COA | ZhenAn quality team | Si, Al, Ca, C, S, P, Mn, batch number and product grade |
| Sieve Analysis Report | ZhenAn quality team | 10–50 mm size result, fines below 10 mm and oversize above 50 mm |
| Packing List | ZhenAn export team | Bag quantity, net weight, gross weight, container number and seal number |
| Commercial Invoice | ZhenAn export team | Product name, grade, quantity, unit price, trade term and payment information |
| Bill of Lading | Shipping line or freight forwarder | Shipment evidence, container information and cargo title document |
7. Ferrosilicon Grade Selection by Application
The following selection table links each application to a fixed product recommendation. This avoids unclear grade selection during ferrosilicon procurement.
| Application Condition | Recommended Grade | Order Specification |
|---|---|---|
| General carbon steel deoxidation | FeSi75 | 72–78% Si, 10–50 mm, fines ≤5%, 1 mt jumbo bag |
| Cost-controlled carbon steel production | FeSi72 | 70–73% Si, 10–50 mm, fines ≤5%, 1 mt jumbo bag |
| Low-carbon or cleaner steel grades | FeSi75 Low-Al | 72–78% Si, Al ≤0.5%, 10–50 mm, MTC/COA required |
| Foundry silicon adjustment | FeSi65 | 63–68% Si, 10–50 mm, fines ≤5%, 1 mt jumbo bag |
| Ductile iron inoculation | FeSi inoculant | Use FeSi-based inoculant for inoculation; use FeSiMg for nodularizing |
| Aluminum alloy silicon addition | Silicon metal, not standard ferrosilicon | Choose silicon metal when low Fe content is required |
8. How ZhenAn Checks Ferrosilicon Before Shipment
We supply FeSi75, FeSi72 and FeSi65 for steelmaking, foundry and metallurgical use. Before shipment, our factory checks ferrosilicon chemical composition, ferrosilicon particle size, fines tolerance, jumbo bag condition, MTC/COA documents and container loading records.
- Grade confirmation: We confirm FeSi75 specification, FeSi72 grade or FeSi65 grade before quotation.
- Chemical checking: We provide ferrosilicon MTC or ferrosilicon COA with Si and FeSi impurity limits.
- Particle size checking: We check 10–50 mm lump size and fines ≤5% below 10 mm for standard steelmaking supply.
- Packing checking: We use 1 mt jumbo bag packing for standard export shipment.
- Document support: We provide MTC/COA, packing list, commercial invoice and bill of lading for export orders.
Frequently Asked Questions About Ferrosilicon Specifications
Q:What is ZhenAn standard FeSi75 specification?
A:ZhenAn standard FeSi75 specification is 72–78% Si, 10–50 mm lump size, fines ≤5% below 10 mm, 1 mt jumbo bag packing, and MTC/COA documents showing Si, Al, Ca, C, S, P and Mn.
Q:What is the difference between FeSi75, FeSi72 and FeSi65?
A:FeSi75 contains 72–78% Si and is used for steel deoxidation and silicon alloying. FeSi72 contains 70–73% Si and is used for cost-controlled carbon steel production. FeSi65 contains 63–68% Si and is used for foundry silicon adjustment and lower silicon addition.
Q:What FeSi impurity limits are listed on the ferrosilicon MTC?
A:The ferrosilicon MTC lists Si, Al, Ca, C, S, P and Mn. For FeSi75 standard grade, our quotation values are Si 72–78%, Al ≤1.5%, Ca ≤1.0%, C ≤0.15%, S ≤0.025%, P ≤0.04% and Mn ≤0.50%.
Q:What ferrosilicon particle size does ZhenAn quote for steelmaking?
A:We quote 10–50 mm lump ferrosilicon for standard steelmaking use. The standard fines tolerance is ≤5% below 10 mm, and the standard packing is 1 mt jumbo bag.
Q:What is the bulk density of 10–50 mm FeSi75 lump?
A:For 10–50 mm FeSi75 lump, we use 1.51–1.60 t/m³ as the ferrosilicon bulk density value for quotation and container loading review.
Q:What documents come with a ferrosilicon shipment?
A:Our standard ferrosilicon shipment documents include MTC/COA, packing list, commercial invoice and bill of lading. The MTC/COA shows product grade, batch number, Si content and FeSi impurity limits.
Q:What information should I send before requesting a ferrosilicon quotation?
A:Please send FeSi grade, required Si content, impurity limits, particle size, fines tolerance, packing method, order quantity, destination port and trade term. For standard steelmaking use, send FeSi75 10–50 mm, fines ≤5%, 1 mt jumbo bag and destination port.
Need Ferrosilicon Specifications and Price?
We supply FeSi75, FeSi72 and FeSi65 with fixed ferrosilicon specifications for steelmaking, foundry and metallurgical use. Before quotation, we confirm Si content, FeSi impurity limits, ferrosilicon particle size, fines tolerance, 10–50 mm lump supply, 1 mt jumbo bag packing, ferrosilicon MTC, ferrosilicon COA and FOB/CIF price terms.
Send us your required grade, particle size, quantity, packing method and destination port. We will reply with specification, document support and quotation.
Specification Note: The default values in this article describe ZhenAn standard quotation specifications for ferrosilicon supply, including FeSi75, FeSi72, FeSi65, 10–50 mm lump size, fines ≤5%, 1 mt jumbo bag packing and MTC/COA documents. For low-Al, low-Ca, 0–3 mm, 3–10 mm, 10–100 mm, different packing or special steel grades, we issue a separate written specification before quotation.
