What other functions do ferrosilicon 75 have that you don’t know about?

Ferrosilicon 75 (FeSi75, silicon content 72%-80%), besides its core functions of deoxidation and alloying in steelmaking, also has multiple hidden values ​​in casting inoculation and performance optimization. It is particularly effective in improving the graphite morphology and mechanical properties of ductile iron and gray cast iron. Accurately utilizing these functions can help enterprises reduce costs and increase efficiency.

Core Advantages: Fast and stable inoculation effect; performance improvement can be achieved with an addition of only 0.2%-0.8% per ton of casting, offering a much higher cost-performance ratio than dedicated inoculants.

Form and Packaging: 5-10mm size specifically for inoculation, packaged in moisture-proof bags (25kg/bag) or ton bags. International transportation requires sealing to prevent oxidation.

(1) Hidden Function 1: Casting Inoculation Core Agent, Precisely Controlling Graphite Morphology

Mechanism of Action: Silicon acts as a heterogeneous nucleation core, promoting graphitization precipitation and inhibiting white cast iron formation (free cementite formation); trace elements such as calcium and aluminum work synergistically to improve graphite spheroidization rate and roundness, preventing spheroidization decay;

 Quantitative Effects by Casting Type:

Ductile Cast Iron (QT450-10): With an addition of 0.3%-0.5%, the graphite spheroidization rate increases from 80% to 90%-95%, the number of graphite nodules increases from 100/mm² to 150-200/mm², and the tendency to white cast iron decreases by 90%;

Gray Cast Iron (HT300): With an addition of 0.4%-0.6%, graphite is evenly distributed in fine flakes, and the number of eutectic groups increases. 60%, to avoid central porosity in thick-walled castings;

(2) Hidden function two: bidirectional optimization of mechanical properties, taking into account both strength and toughness

Mechanism of action: refines grains and graphite structure, reduces stress concentration, and improves toughness; silicon solid solution strengthens the ferrite matrix, improving the strength and hardness of castings;

 Quantitative performance improvement:

Ductile cast iron: adding 0.3%-0.5%, tensile strength increases from 450MPa to 500-550MPa (increase of 11%-22%), impact toughness (-20℃) increases from 60J/cm² to 80-90J/cm² (increase of 33%-50%), elongation increases from 10% to 15%-18%;
Gray cast iron: adding 0.4%-0.6%, tensile strength increases from 300MPa to 350-380MPa (increase of 17%-27%), hardness (HB) increases from 180-200 increased to 220-240, wear resistance improved by 30%-40%;

(3) Hidden function three: improve casting process performance and reduce production defects

Mechanism of action:Reduce the viscosity and surface tension of molten iron, improve fluidity, and improve the filling capacity of castings;
Reduce solidification shrinkage stress and avoid defects such as cracks and cold shuts;

 Quantitative effect:

Thin-walled castings (thickness ≤ 5mm): Adding 0.5%-0.7%, the defect rate of "insufficient pouring" and "cold shuts" decreased from 5% to below 1%, and the surface finish Ra decreased from 1.2μm to 0.8μm;
Thick-walled castings (thickness ≥ 50mm): Adding 0.6%-0.8%, the solidification shrinkage rate decreased from 6.5% to 4.8%, and the internal shrinkage cavity and porosity defect rate decreased by 70%;