Ferrosilicon 70 is mainly composed of two elements, silicon and iron, of which the silicon content is about 70%, and the rest is iron and a small amount of impurity elements, such as aluminum, calcium, manganese, sulfur, phosphorus, etc. The size range is between 10-50mm. This larger ferrosilicon particle has good fluidity and air permeability. When added to the furnace, it can be more evenly distributed in the molten metal, which is conducive to the full reaction. It is also convenient for storage and transportation and reduces dust flying.

Ferro silicon 70 10-50mm

chemical composition

Grade	Chemical Composition(mass fraction)%
	Si	Al	Ca	Mn	Cr	P	S	C
	≥	≤
FeSi90Al1.5	87.0~95.0	1.5	1.5	0.4	0.2	0.04	0.02	0.2
FeSi9oAl3.0	87.0~95.0	3	1.5	0.4	0.2	0.04	0.02	0.2
FeSi75Al0.5-A	74.0~80.0	0.5	1	0.4	I0.3	0.035	0.02	0.1
FeSi75Al0.5-B	72.0~80.0	0.5	1	0.5	0.5	0.04	0.02	0.2
FeSi75Al1.0-A	74.0~80.0	1	1	0.4	0.3	0.035	0.02	0.1
FeSi75Al1.0-B	72.0~80.0	1	1	0.5	0.5	0.04	0.02	0.2
FeSi75Al1.5-A	74.0-80.0	1.5	1	0.4	0.3	0.035	0.02	0.1
FeSi75Al1.5-B	72.0~80.0	1.5	1	0.5	0.5	0.04	0.02	0.2
FeSi75Al2.0-A	74.0~80.0	2	1	0.4	0.3	0.035	0.02	0.1
FeSi75Al2.0-B	72.0~80.0	2		0.5	0.5	0.04	0.02	0.2
FeSi75-A	74.0~80.0			0.4	0.3	0.035	0.02	0.1
FeSi75-B	72.0~80.0			0.5	0.5	0.04	0.02	0.2
FeSi65	65.0~72.0			0.6	0.5	0.04	0.02

The uses of ferrosilicon 70 with a size of 10-50mm are mainly in the following aspects

Steelmaking field:

Deoxidizer:

In the steelmaking process, fesi 70 has a strong affinity with oxygen and can react with oxygen in molten steel to generate oxides such as silicon dioxide. These oxides can float to the surface of molten steel and be removed, thereby effectively reducing the oxygen content in molten steel, reducing defects such as pores and inclusions in steel, improving the quality and density of steel, and enhancing the toughness and other properties of steel.

Alloying agent:

Adding ferrosilicon 70 to steel can improve the strength, hardness, wear resistance, corrosion resistance and other properties of steel. For example, when smelting structural steel, tool steel, spring steel and silicon steel for transformers, adding an appropriate amount of ferrosilicon 70 can make the silicon content in the steel reach the specified range, thereby improving the organizational structure and performance of the steel and meeting the requirements of steel performance in different engineering fields.

Foundry industry:

Inoculant:

In the production of gray cast iron, it can promote the graphitization process, make the graphite morphology finer and more evenly distributed, thereby improving the mechanical properties of cast iron. It can act as the core of graphite, promote the precipitation of graphite in a finer form, refine the matrix structure of cast iron, reduce the pearlite interlamellar spacing, increase the number of pearlites, and thus improve the strength and toughness of cast iron, and improve its wear resistance and processing performance.

Spheroidizing agent:

In the production of ductile iron, it is an important auxiliary material for spheroidizing agent. It works together with other spheroidizing elements to effectively prevent the formation of carbides, promote the spheroidization of graphite, increase the number of graphite balls in cast iron, make the ball diameter more uniform, and improve the roundness, thereby significantly improving the mechanical properties of ductile iron, making its strength, toughness, ductility, etc. close to or reach the level of steel, greatly expanding the application range of cast iron.

Ferro alloy production

Due to the great chemical affinity between silicon and oxygen, and the low carbon content of high-silicon ferrosilicon, it is a commonly used reducing agent in the production of low-carbon ferroalloys in the ferroalloy industry.

ferro silicon 70 10-50mm

Approximate addition ratio range in different steelmaking scenarios

Ordinary carbon steelmaking

When it is used as a deoxidizer, its addition amount generally accounts for about 0.2% - 0.5% of the total mass of molten steel. If the initial oxygen content of the molten steel is relatively high, or there are slightly higher requirements for the density and purity of the steel, such as for the manufacture of some structural steel for construction, the addition amount may be close to 0.5%; while for ordinary civil construction steel and other situations where the deoxidation requirements are not so strict, the addition amount may be 0.2% - 0.3% to meet the basic deoxidation requirements, reduce the oxygen content in the molten steel, and reduce defects such as pores and inclusions.

When added as an alloying agent to increase the silicon content of steel to improve performance, the addition ratio will vary depending on the different requirements of the target steel for silicon content. It usually accounts for about 0.3% - 1% of the total mass of molten steel. For example, when producing some ordinary carbon steels that require certain wear resistance and strength, the addition amount is about 0.3% - 0.6%; if the performance is to be further improved and used to manufacture carbon steel products with higher requirements for hardness, the addition amount may be increased to 0.6% - 1%.

Low-alloy structural steel steelmaking

When used as a deoxidizer, the addition amount of ferrosilicon 70 accounts for about 0.3% - 0.6% of the total mass of molten steel. Because low-alloy structural steel has relatively higher requirements for steel quality, the addition amount of deoxidation is usually slightly higher than that of ordinary carbon steel, in order to better remove oxygen from molten steel, ensure good comprehensive performance of steel, reduce internal defects, and facilitate subsequent processing and application.

As an alloying agent, in order to meet the silicon content in low-alloy structural steel to obtain better comprehensive properties such as strength, toughness, and corrosion resistance, its addition ratio is generally around 0.5% - 1.2%. Different alloy composition designs and target performance requirements will adjust the addition amount within this range. For example, for low-alloy structural steel that focuses on improving strength and corrosion resistance, the addition amount may be closer to 1% - 1.2%.

Special steel steelmaking (such as spring steel, bearing steel, etc.)

In the steelmaking process of such special steels with strict performance requirements, when ferrosilicon 70 is used as a deoxidizer, the addition amount often accounts for about 0.4% - 0.8% of the total mass of the molten steel, ensuring that the molten steel has extremely high purity, reducing impurities and oxygen content, and laying the foundation for the subsequent formation of excellent organizational structure and performance.

When used as an alloying agent, since spring steel, bearing steel, etc. have precise requirements for silicon content to achieve specific elasticity, hardness, wear resistance and other properties, the addition ratio of ferrosilicon 70 is usually around 0.8% - 1.5%. The addition amount is finely adjusted according to the composition specifications of the specific steel and the characteristics of the production process to ensure that the various performance indicators of the steel meet high quality standards.

ferro silicon 70 10-50mm