ferro silicon inoculant with silicon content 75% min,particle appearance showing fine particle texture, dark gray color and metallic sheen with specifications below

ferro silicon inoculant silicon content 75% min,size 0.2-0.8mm particle with ruler for size reference and chemical specifications table

ferro silicon inoculant silicon content 75% min,size 3-8mm particle with ruler for size reference and chemical specifications table

FeSi 75% Inoculant – High‑Silicon Alloy for Demanding Gray & Ductile Iron Castings

Premium ferrosilicon with 75‑78% Si, offering maximum graphitizing power, strong chill reduction, and improved ferrite formation in high‑quality iron castings.

Main Composition	Si 75-78%, Al ≤1.5%, Ca ≤1.0%, Fe balance
Form	Lumps/Granules/Custom
Application	High‑grade ductile iron, ferritic ductile iron, thin‑wall castings, pressure pipe fittings, automotive safety parts

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FeSi 75% Inoculant – Superior Graphitization for High‑Performance Castings

This ferrosilicon inoculant with 75–78% silicon is a high‑purity alloy engineered for foundries that demand maximum graphitizing power and consistent nucleation. With a silicon content at the upper end of the standard range, FeSi 75% provides exceptional chill reduction, promotes a ferritic matrix in ductile iron, and ensures uniform graphite distribution. The controlled aluminium (≤1.5%) and calcium (≤1.0%) levels guarantee effective deoxidation while minimizing dross and inclusions, making it ideal for critical safety components and pressure‑tight castings.

Core Advantages & Technical Features

Maximum Graphitizing Power: The high silicon concentration (75‑78%) delivers strong carbide suppression, even in rapidly cooling thin sections, eliminating chill and improving machinability.
Ferrite Promotion in Ductile Iron: Encourages a high ferrite content, enhancing ductility, impact resistance, and machinability in as‑cast or annealed ductile iron components.
Consistent Nodule Count: Provides a high density of small, well‑formed graphite nodules, contributing to superior tensile and fatigue properties.
Low Dross & Inclusion Tendency: Optimized Al and Ca levels minimize slag formation, ensuring clean castings suitable for high‑pressure applications.
Custom Sizing for All Methods: Available in a wide range of particle sizes to suit ladle, stream, in‑mould, or wire feeding, ensuring optimal dissolution and recovery.

Note: This product is non‑radioactive and fully complies with REACH and RoHS environmental standards. Manufactured under ISO 9001 certified processes.

Technical Specifications – Inoculant Grades (FeSi 75% & others)

Below is the chemical composition of our FeSi 75% (highlighted) compared with other common inoculant grades. Custom compositions and impurity limits are always available on request.

Chemical Composition (Typical Values, % by weight)

Grade / Designation	Si (%)	Ba (%)	Al (%)	Ca (%)	Fe & Others
FeSi 75% (Premium)	75-78	–	≤1.5	≤0.5-1.5	Balance
FeSiBa 1-2% Ba	70-75	1.0-2.0	1.0-1.5	0.6-3.0(customizable)	Balance
FeSiBa 2-4% Ba	70-75	2.0-4.0	1.0-1.5	0.6-3.0	Balance
FeSiBa 4-6% Ba	65-70	4.0-6.0	1.0-1.5	1.0-3.0(customizable)	Balance
FeSi 72%	72-75	–	≤1.5	≤1.0	Balance
FeSi 74%	74-75	–	≤1.5	0.5-1.5	Balance

Physical & Thermal Properties (FeSi 75%)

Property	Typical Value / Range	Remarks
Melting Range (Solidus/Liquidus)	1200°C - 1320°C (2192°F - 2408°F)	Slightly lower melting onset due to higher silicon, promoting rapid dissolution
Specific Gravity (Density at 20°C)	3.1 - 3.4 g/cm³	Typical for high‑silicon ferrosilicon
Bulk Density	Approx. 1.7 - 2.1 g/cm³ (106 - 131 lbs/ft³)	Depends on particle size distribution
Thermal Expansion Coefficient (20-1000°C)	~11.5 × 10⁻⁶ /K	–
Microstructure	FeSi₂ + FeSi phases	Homogeneous silicon distribution

Available Particle Sizes (Customizable for FeSi 75%)

Ladle Addition (General Foundry): 5-30 mm, 10-50 mm (optimal dissolution).
Late / Stream Inoculation: 0.2-0.8 mm, 0.5-1.5 mm (excellent flowability).
Wire Feeding: 0.5-3 mm (consistent fill for cored wire).
In‑mold / Sprue Inoculation: 1-3 mm, 3-8 mm (controlled solubility).
Lumps (Furnace Addition): 10-100 mm (custom).

Processing Note: Manufactured via controlled casting or granulation to guarantee homogeneous composition and minimal fines.

Key Applications & Recommended Addition Rates – FeSi 75%

FeSi 75% is the preferred inoculant for high‑quality ductile and gray iron castings where maximum graphitization and ferrite promotion are desired:

High‑Ductility Ductile Iron: Automotive safety parts (control arms, knuckles), pipe fittings, and wind turbine components requiring high elongation.
Typical Addition: 0.3% – 0.7% of melt weight (depending on base sulfur and magnesium residuals).
Ferritic Ductile Iron Castings: Excellent for as‑cast ferritic grades (e.g., 400‑12, 450‑10), promoting high ferrite content and good machinability.
Thin‑Wall Castings (<5 mm): Provides powerful chill reduction, ensuring carbide‑free edges in complex, thin‑section castings like housings and brackets.
Pressure Pipe and Fittings: Ensures uniform graphite structure and pressure tightness in centrifugally cast pipes.
High‑Strength Gray Iron (≥250 MPa): Boosts tensile strength by promoting type A graphite and reducing undercooled graphite.

Note: Optimal addition rate should be fine‑tuned based on base iron composition (S, O, trace elements), target matrix, and pouring conditions. We recommend foundry trials with incremental adjustments.

Packaging & Logistics – FeSi 75% Inoculant

Packaging Options

1‑ton Jumbo Bags: Standard for bulk orders, with inner moisture‑proof liner.
25kg / 50kg Bags: For smaller foundries or trial batches.
Custom Packaging: Big bags with pallets, stretch‑wrapped, or sealed drums available.

Logistics Information

Parameter	Details
Minimum Order Quantity	20 metric tons (trial orders of 5‑10 t possible upon request)
Lead Time	15‑20 days after confirmation
Port of Loading	Tianjin, Shanghai, Qingdao (other ports on request)
Shipping Options	FOB, CIF, CFR, DAP, DDP

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FAQ – FeSi 75% High‑Silicon Inoculant

❓ How does FeSi 75% compare with FeSi 72% or 74%?+

FeSi 75% contains the highest silicon level (75‑78%) among standard ferrosilicon inoculants. This translates into the strongest graphitizing power per unit addition. It is particularly effective in promoting ferrite in ductile iron and in eliminating chill in thin sections. While FeSi 72% and 74% are also excellent inoculants, FeSi 75% is the choice when maximum nucleation and ferrite promotion are required, especially for high‑elongation ductile iron grades.

Is it possible to entrust a third-party inspection to check the quality before shipment? +

Certainly, we support third-party inspections by internationally recognized quality inspection agencies such as SGS and BV to verify product quality before shipment. The inspection covers product appearance, weighing, dimensions, and chemical composition analysis. The entire inspection process will be documented with photos and written records, which will be provided to you together with the final inspection report. This ensures you have no concerns regarding product quality.

❓ What is the optimal base sulfur range for FeSi 75%?+

FeSi 75% performs optimally in irons with base sulfur between 0.008% and 0.018%. The alloy's aluminium and calcium (≤1.5% Al, ≤1.0% Ca) work synergistically with sulfur to form numerous sulfide nucleation sites. For very low sulfur irons (<0.005%), a slight sulfur addition or the use of a sulfur‑bearing inoculant is beneficial to maximize nodule count. In higher sulfur irons (>0.025%), it still provides good inoculation but may require slightly higher addition rates.

❓ Is FeSi 75% suitable for thin‑wall castings?+

Absolutely. In fact, its high silicon content makes it one of the best choices for thin‑wall castings (down to 3 mm) where rapid cooling can lead to carbide formation. Using a fine particle size (e.g., 0.2‑0.8 mm) and late addition ensures maximum chill reduction and a fully ferritic matrix in thin sections. Many foundries producing automotive brackets and housings rely on FeSi 75% for this reason.

❓ How does FeSi 75% compare with zirconium or rare‑earth based inoculants?+

Zirconium and rare‑earth inoculants offer specialized benefits: Zr helps with nitrogen control, while rare earths provide extreme nucleation but at higher cost. FeSi 75% is a cost‑effective, high‑performance general‑purpose inoculant that delivers excellent graphitization and ferrite promotion for the vast majority of ductile and gray iron applications. For nitrogen‑sensitive melts, a combination of FeSi 75% with a small Zr addition may be recommended, but for standard high‑quality castings, FeSi 75% alone is sufficient.

❓ What storage conditions are recommended for FeSi 75%?+

FeSi 75% is stable and non‑hygroscopic. Store in a dry, covered area (≤60% relative humidity) in original sealed bags or silos. If material becomes damp (e.g., due to condensation), drying at 80‑100°C for 1‑2 hours restores its performance. Avoid prolonged exposure to rain or high humidity to prevent surface oxidation, which may affect flowability.

❓ Can FeSi 75% be used together with a late‑stage inoculant?+

Yes, many foundries use FeSi 75% as a primary ladle inoculant (0.3‑0.5%) and then add a small amount (0.1‑0.2%) of a stronger late‑stage inoculant (e.g., FeSiZr or a rare‑earth mix) just before pouring. This duplex practice further refines graphite structure and eliminates any residual chill in complex castings. For ferritic ductile iron, this combination can yield exceptionally high nodule counts and elongation. We can recommend compatible late‑stage products based on your casting portfolio.