Description of Inoculant

Inoculants are necessary additives in the production of cast iron. A little inoculant can significantly improve the microstructure of cast iron and improve the properties of gray cast iron. Inoculants can also promote graphitization, improve the morphology and distribution of graphite, increase the number of eutectic clusters, and refine the matrix structure. The main components of inoculants are silicon, aluminum, barium, and calcium.

  Inoculant of Cast Iron

Classification of Inoculants

The main types of inoculants are Ferrosilicon inoculant(FeSi inoculant), Calcium silicon barium inoculant(CaSiBa inoculant), Calcium silicon inoculant(CaSi inoculant), Ferro Silicon Barium Inoculant（FeSiBa inoculant）, etc.

FeSi Inoculant

Ferrosilicon inoculant is a ferroalloy, made of coke, steel scrap, quartz (or silica), and smelted in an electric furnace. It is mainly composed of silicon and iron. Silicon and oxygen are easy to synthesize silica, so ferrosilicon is often used as a deoxidizer in steelmaking. Ferrosilicon inoculant conventional sizes are 0.2-0.8mm, 1-3mm, and 3-8mm.

75 ferrosilicon is the more commonly used inoculant. The US standard stipulates that the aluminum content is 0.75-1.75%, and the calcium content is 0.5-1.5%. There are different models of China’s ferrosilicon standards. The upper limit of aluminum content is 0.5%, 1.0%, 1.5%, and 2.0%. The upper limit of the calcium content is 1.0%. However, the aluminum content in the molten iron should not be too high, and the addition of 0.01% aluminum may cause subcutaneous pores in the casting.                                      

CaSiBa Inoculant

• Calcium silicon barium inoculant increase the graphitization core, and refinement of graphite, promote getting A-type graphite from the Gtey iron castings, increase the intensity, fo ductile iron parts, and can makes the graphite in ductile iron ball small, and round, improve the nodulizing grade.

• Effectively reduce molten iron super-cooling degree, promote the precipitation of graphite, significantly reduce chilling tendency, reduce the relative hardness, and improve casting machinability.

• Easy to dissolve and absorb than the average inoculant, can reduce the gas content in the molten iron.

• High ability to recession-proof, At the same time it prevents relevant nodulizing decline, wall thickness sensitivity is small, well-closed formation.   

CaSi Inoculant

Silicon-calcium inoculant is a kind of inoculant that can promote graphitization, reduce whitening tendency, improve graphite morphology and distribution, increase the number of eutectic groups, and refine the matrix structure. ) have a good effect. It is mainly suitable for general or post-instantaneous pregnancy in various situations. Calcium silicon inoculant improves the uniformity of the section, reduces the tendency of shrinkage, and has the characteristics of stable chemical composition, uniform processing particle size, small deviation of composition and quality, low melting point, easy melting and absorption, and very little scum.

The Advantages of LSFerroalloy

• Steady product composition, small deviation of the main elements;

• Uniform particle size, precise screening, no impurities;

• Good function of eliminating or reducing the chilling tendency;

• Avoid supercooled texture;

• Reduce the sectional sensitivity of the casting, so that has a small difference between the microstructure of the thin and thick sections of the casting, and the difference in hardness is also small;

• Promote the nucleation of eutectic cells and increase the number of eutectic cells;

• Improve the mechanical properties of castings;

• Increase the number of graphite nodules, eliminate cementite, and improve plasticity and toughness in molten iron after spheroidization.