Steel FeSi75
ASTM A100
FeSi75 is a ferrosilicon master alloy (Fe-Si, typically 45–90 % Si) supplied to A100 as a deoxidizer, silicon alloy addition and cast-iron inoculant, not as a finished part material.
Reference datasheet — FeSi75 is not in the instant-quote catalog. Upload your part and an engineer will quote it in this grade or suggest the closest stocked equivalent.
Values for the LUMP-10-50-A condition
FeSi75 tempers and conditions
FeSi75 is supplied in 8 conditions, soft to hard. LUMP-10-50-A is the default FabDigit quotes; the values on this page are for it.
Compare all 8 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Al ≤2.0 %, B-class | Lowest-cost chemistry for cast iron and non-critical deoxidation where Al and P limits are relaxed. | 110 | 0 | 66 HRC | 0.31 % IACS | |
Al ≤1.5 %, A-class impurities | Workhorse export/mill grade for carbon and low-alloy steel deoxidation. | 115 | 0 | 66 HRC | 0.3 % IACS | |
LUMP-10-50-ADefault Lump 10–50 mm, A-class | Standard stocked size and chemistry for ladle deoxidation and silicon alloying in steelmaking. | 120 | 0 | 67 HRC | 0.29 % IACS | |
Lump 10–100 mm, A-class | Coarser sizing for large ladles and electric-furnace charging where slower dissolution is acceptable. | 120 | 0 | 67 HRC | 0.29 % IACS | |
Al ≤1.0 %, A-class impurities | Common intermediate chemistry balancing price against Al limit for general steel deoxidation. | 120 | 0 | 67 HRC | 0.29 % IACS | |
Low-aluminium, A-class impurities | Choose when aluminium pick-up must be minimised (clean steel, tyre cord, silicon steel). | 125 | 0 | 67 HRC | 0.29 % IACS | |
Low-Al / low-Ca refining grade (Al ≤0.5 %, Ca ≤0.5 %, C ≤0.10 %) | For stainless, silicon-steel and cored-wire feedstock where Ca and C additions must be tightly controlled. | 130 | 0 | 68 HRC | 0.28 % IACS | |
Cold worked | Wire-injected form for precise late silicon trimming and inoculation in continuous casting. | 200 | 310 | 25 | 110 HB | 9 % IACS |
Supply forms, finishes and certifications
Ways FeSi75 is supplied — form, process route, surface or paperwork — without a datasheet of their own. The property values above apply.
| Option | What it is | Type |
|---|---|---|
PWD-0-3 | Powder / granule 0–3 mm | Supply form |
PWD-200M | Ball-milled fine powder, −200 mesh | Supply form |
BRIQ | Briquette | Surface finish |
What is FeSi75?
FeSi75 is a ferrosilicon master alloy (Fe-Si, typically 45–90 % Si) supplied to A100 as a deoxidizer, silicon alloy addition and cast-iron inoculant, not as a finished part material. It is ordered by chemistry and size: 10–50 mm and 10–100 mm lump, aluminium-controlled grades at 0.5, 1.0, 1.5 and 2.0 % Al, low-calcium, briquettes, 0–3 mm and 200-mesh powder, and cored wire, with bulk density around 3 g/cm³. The alloy is a hard, brittle intermetallic, so it cannot be machined, welded or formed, and fines must be kept dry and in ventilated packaging. FeSi75 has a density of 3 g/cm³ (0.108 lb/in³), lighter than 100% of steel grades. It melts at 1,210°C (2,210 °F). FeSi75 has a tensile strength of 120 MPa (17.4 ksi), weaker than 100% of steel grades. Elongation at break is 0% and the elastic modulus is 160 GPa (23.2 Msi).
What is FeSi75 used for?
- Steel deoxidation
- Ductile/gray iron inoculation
- Alloy addition in foundries
- Silicon steel raw material
Advantages
- Lightweight — 3 g/cm³ (0.108 lb/in³), better than 100% of steel grades
- High service temperature — 800°C (1,472 °F), better than 100% of steel grades
- Good corrosion resistance — 55/100, better than 99% of steel grades
Limitations
- Limited ductility — 0%, worse than 100% of steel grades
- Low fracture toughness — 2 MPa·√m (1.82 ksi·√in), worse than 100% of steel grades
- Low electrical conductivity — 0.29 % IACS, worse than 100% of steel grades
- Difficult to machine — 3/100, worse than 100% of steel grades
- Difficult to weld — 3/100, worse than 100% of steel grades
FeSi75 properties
Typical room-temperature values for FeSi75-LUMP-10-50-A; bars are the position among steel grades.
Physical3
FeSi75 has a density of 3 g/cm³ (0.108 lb/in³), lighter than 100% of steel grades. It melts at 1,210°C (2,210 °F).
Mechanical10
FeSi75 has a tensile strength of 120 MPa (17.4 ksi), weaker than 100% of steel grades. Elongation at break is 0% and the elastic modulus is 160 GPa (23.2 Msi).
Thermal5
FeSi75 is rated for continuous service to 800°C (1,472 °F). It conducts heat at 12 W/m·K (6.93 BTU/hr·ft·°F), worse than 99% of steel grades. Thermal expansion is 11 µm/m·K (6.11 µin/in·°F).
Electrical3
FeSi75 conducts electricity at 0.29 % IACS, worse than 100% of steel grades.
Chemical & Environmental2
Corrosion resistance is good (55/100), better than 99% of steel grades.
Sustainability3
Producing a kilogram of FeSi75 takes about 65 MJ of energy and emits 5.5 kg of CO₂ — more than 96% of steel grades. Typical recycled content is 2%.
Manufacturability4
FeSi75's machinability is not recommended (3/100, worse than 100% of steel grades); weldability not recommended (3/100); formability not recommended (1/100).
Common Calculations4
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Strength versus weight in the steel family
Yield strength against density for every steel grade FabDigit runs. FeSi75 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with FeSi75
Is FeSi75 easy to machine?
Not machinable — hard, brittle intermetallic; sized only by crushing, jaw/roll milling and screening.
Can FeSi75 be welded?
Not weldable as a product; consumed as a silicon source in steel deoxidation, welding-flux and electrode coatings.
Can FeSi75 be formed, bent or molded?
No plastic forming; fines are agglomerated by briquetting with binder or sheathed into cored wire.
FeSi75 chemical composition (wt %)
Limits by weight percent from the governing specification, written the way the spec states them — a single maximum for impurities, a range for alloying elements, and the base element as balance. Nominal is the typical mid-range value.
| Element | Spec limit (wt %) | Nominal |
|---|---|---|
| SiGB/T 2272 / ISO 5445 FeSi75 range | 72 – 80 | 75 |
| Al0.5 / 1.0 / 1.5 / 2.0 % sub-grades | ≤ 1.5 | 1 |
| Ca | ≤ 1 | 0.5 |
| C | ≤ 0.2 | 0.1 |
| PA-class | ≤ 0.04 | 0.03 |
| S | ≤ 0.02 | 0.01 |
| Mn | ≤ 0.5 | 0.3 |
| Cr | ≤ 0.5 | 0.2 |
| Ti | ≤ 0.1 | 0.05 |
| Fe | balance |
What surface finishes work on FeSi75?
No surface finishing — supplied crushed and screened, kept dry and in ventilated packaging to avoid gas evolution.
Surface treatments FabDigit runs on steel parts — pick them in the quote configurator or call them out on the drawing. Each links to its datasheet in the surface-finish library (thickness, specs, call-out, material verdicts).
Organic Coating
Black / Phosphate
Thermal Spray
Equivalent designations
Standards and trade names that resolve to Steel FeSi75 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- ASTM
- A100
- Other
- FS75
How much does FeSi75 cost?
FeSi75 is a budget-cost steel ($), cheaper than about 90% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
FeSi75 — frequently asked
What is FeSi75 used for?
FeSi75 is typically used for steel deoxidation, ductile/gray iron inoculation, alloy addition in foundries and silicon steel raw material. In short: standard silicon master alloy; melt addition, not stock; sized by crushing and screening.
What is the tensile strength of FeSi75?
FeSi75 has a typical tensile strength of 120 MPa (17.4 ksi) — weaker than 100% of steel grades. Strength varies by condition: see the 8 listed tempers.
Is FeSi75 easy to machine?
Not especially — machinability is rated not recommended (3/100, worse than 100% of steel grades). Not machinable — hard, brittle intermetallic; sized only by crushing, jaw/roll milling and screening.
Can FeSi75 be welded?
Not readily — weldability is rated not recommended (3/100). Not weldable as a product; consumed as a silicon source in steel deoxidation, welding-flux and electrode coatings.
What surface finishes work on FeSi75?
No surface finishing — supplied crushed and screened, kept dry and in ventilated packaging to avoid gas evolution.
Can FeSi75 be formed, bent or molded?
No plastic forming; fines are agglomerated by briquetting with binder or sheathed into cored wire.
What is the maximum service temperature of FeSi75?
FeSi75 is rated for continuous use to about 800°C (1,472 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between FeSi75 LUMP-10-50-A and FeSi75-CW?
LUMP-10-50-A is the default condition — standard stocked size and chemistry for ladle deoxidation and silicon alloying in steelmaking. CW: wire-injected form for precise late silicon trimming and inoculation in continuous casting.
How much does FeSi75 cost?
FeSi75 is a budget-cost steel ($), cheaper than about 90% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
Sources
- GB/T 2272 (Ferrosilicon) — SAC (2020)
- ISO 5445 Ferrosilicon — Specification and conditions of delivery — ISO (1980)
- ASTM A100 Standard Specification for Ferrosilicon — ASTM International (2018)
- ASM Handbook Vol.3: Alloy Phase Diagrams (Fe–Si) — ASM International (1992)
Property data is compiled from published supplier and standards handbooks and normalised for comparison; hardness values on non-Brinell scales are converted approximately for charting only. Manufacturability limits are FabDigit quote-engine defaults and may be relaxed by engineering review. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.