What is Silicon 3303?
Silicon 3303 (Industrial Silicon 3303) is a mid-to-high-end core grade under the Chinese national standard GB/T 2881-2014 "Industrial Silicon". Its core specifications are defined as follows: silicon (Si) content ≥99.37%, iron (Fe) ≤0.30%, aluminum (Al) ≤0.30%, and calcium (Ca) ≤0.03%. Its four-digit code directly corresponds to the upper limit of key impurity content, making it an essential basic material in fields such as organosilicon monomers, electronic-grade polycrystalline silicon raw materials, and high-end aluminum alloys.
Silicon 3303 grade coding logic: The core meaning of the four digits
The first digit, "3": represents an iron (Fe) content ≤0.30% (mass fraction). Iron is a major impurity in industrial silicon; excessive amounts can affect the strength and conductivity of downstream products. The strict control of iron in 3303 makes it suitable for mid-to-high-end production needs.
The second "3": indicates an aluminum (Al) content ≤0.30% (mass fraction). Aluminum reduces the high-temperature resistance of industrial silicon, especially in the electronics and organosilicon fields, where controlling the aluminum content directly determines product quality.
The last two "03": indicates a calcium (Ca) content ≤0.03% (mass fraction). Calcium is a harmful impurity in industrial silicon; excessive amounts can lead to inclusions and bubbles during downstream smelting, affecting product molding results.
Silicon 3303 Core Specifications
Chemical Composition
|
Element Name |
Symbol |
National Standard Requirement (Min/Max) |
Typical Commercial Value |
|
Silicon |
Si |
≥99.37% |
99.4% ~ 99.7% |
|
Iron |
Fe |
≤0.30% |
≤0.25% |
|
Aluminum |
Al |
≤0.30% |
≤0.28% |
|
Calcium |
Ca |
≤0.03% |
≤0.025% |
|
Phosphorus |
P |
≤0.005% |
≤0.003% |
|
Boron |
B |
≤0.001% |
≤0.0008% |
|
Total Impurities |
- |
≤0.63% |
≤0.60% |
Physical Properties
|
Item |
Technical Parameter |
|
Appearance |
Silvery-gray metallic luster, clean fracture, free of slag inclusions, no powder agglomeration, and no obvious impurity spots. |
|
Density |
2.33 g/cm³ (at 25°C) |
|
Melting Point |
1414°C |
|
Particle Size (Common in Export) |
Lumps: 10-50mm (≥90%), 10-100mm (≥90%); Granules: 1-10mm; Powder: 30-425 mesh |
|
Hardness |
Mohs Hardness 6.5 - 7.0 |
Comparison of Silicon 3303 with Mainstream Industrial Silicon Grades
|
Grade |
Si ≥% |
Fe ≤% |
Al ≤% |
Ca ≤% |
Core Applications |
|
Silicon 3303 |
99.37 |
0.30 |
0.30 |
0.03 |
Silicone monomers, electronic-grade polysilicon feedstock, high-end aluminum alloys, silane coupling agents. |
|
Silicon 441 |
99.0 |
0.40 |
0.40 |
0.10 |
General silicone, silicone rubber products, aluminum castings, ordinary alloys. |
|
Silicon 553 |
98.5 |
0.50 |
0.50 |
0.30 |
Low-grade aluminum alloys, refractory materials, metallurgical deoxidizers, construction materials. |
|
Silicon 2202 |
99.6 |
0.20 |
0.20 |
0.02 |
Semiconductors, solar-grade polysilicon, high-end electronic components, aerospace materials. |
Silicon 3303 Core Application Areas
Organosilicon Industry (Largest Demand Area in Foreign Trade): As a core raw material for producing organosilicon monomers such as methylchlorosilane, it is further used to manufacture silicone, silicone oil, silicone rubber, silicone resin, and other products. It is widely used in automotive seals, building waterproofing, medical consumables, electronic packaging, and other fields, and is the mainstream grade purchased by organosilicon factories in Europe, America, and Southeast Asia.
In the field of electronic materials: As a basic raw material for electronic-grade polysilicon, after purification, it is used in the production of semiconductor chips, integrated circuits, and photovoltaic cells, meeting the high-end needs of the new energy and electronic technology industries, and is also a key category for overseas electronics companies.
In the field of high-end aluminum alloys: Added to aluminum alloys used in aerospace and automotive lightweighting, it can significantly improve the alloy's strength, corrosion resistance, and casting performance, meeting the needs of high-end manufacturing industries, and is a preferred raw material for overseas buyers in the automotive and aerospace sectors.
In the field of fine chemicals and other fields: Used to produce high-performance silane coupling agents and optical fiber raw materials, meeting the needs of the high-end coatings and communications industries. It can also be used to produce high-end refractory materials and catalysts, with applications covering multiple high-value-added industries.
