Production Technology and Application of Silicon Micropowder

Silicon powder is made of natural quartz (SiO2) or fused quartz (amorphous SiO2 after high temperature melting and cooling of natural quartz), which is crushed, ball milled (or vibration, jet mill), flotation, pickling purification, high-purity water treatment, etc. The micro powder processed by this technology.

Silicon powder is gray or off-white powder, non-toxic, odorless, non-polluting, resistant to temperature, acid and alkali corrosion, poor thermal conductivity, high insulation, high hardness, low swelling, and stable chemical properties. According to the production process, it can be divided into crystalline silicon powder, fused silicon powder, cristobalite silicon powder, and active silicon powder. According to the level, it can be divided into ordinary silicon powder, electrical grade silicon powder, electronic grade silicon powder, fused silicon powder, ultrafine silicon powder, and “spherical” silicon powder. According to the purpose, it can be divided into silicon powder for paint and coating, silicon powder for epoxy floor, silicon powder for rubber, silicon powder for sealant, silicon powder for electronic and electrical plastic packaging materials, and silicon powder for precision ceramics.

Production process of silicon powder

  • The beneficiation and purification of silicon powder raw materials

Mineral beneficiation and purification generally involves crushing, sieving and grinding siliceous raw materials with high impurity content to fully dissociate silica and impurities. In actual production, purification is carried out according to the required quality. Either through flotation, magnetic separation to remove impurities, or through water washing and grading to remove impurities, or pickling to remove impurities, and after drying, it is used as the raw material for silicon micropowder.

  • Production process of silicon powder
  1. Production process of angular silicon powder

Angular silicon micropowder is an irregularly angular silicon micropowder obtained by grinding the raw material of silicon micropowder. The main production equipment of angular silicon powder includes ball mill, powder classifier, vibration mill, and dryer.

  1. Production process of spherical silicon powder

Spherical silicon powder is a kind of high-strength, high-hardness, and emotional spherical particles made of high-quality raw quartz ore and processed by a unique process. The production processes of spherical silicon micropowder abroad include high-temperature melting spray method, gas flame method, hydrolysis method of silicon tetroxide, etc., and control ethyl orthosilicate in the liquid phase. The main production equipment includes a powder quantitative conveying system, a gas volume control and mixing device, a gas fuel high temperature flame spray gun, and a cooling recovery device.

  1. Recovery method of silicon micropowder recovery process

Pulse jet bag dust removal, anti-adhesive big bag dust removal, and electric dust removal.

Application of silicon powder

  • Application fields of general silicon powder products

Ceramics, metallurgical flux, casting and metal surface treatment, electronic component packaging, rubber, high-grade paint, anti-corrosion coatings, welding rod coating, construction mortar and high-strength concrete aggregates, high-grade refractory materials, solar photovoltaic cells, military antenna reflectors, teeth Use materials, environmental protection and oil wells to pressurize.

  • Application fields of fused silica powder products

Fused silicon powder has the characteristics of high purity, excellent electrical properties, high hardness, wear resistance, stable chemical properties, and good whiteness. It is often used in plastic packaging materials for ultra-large-scale integrated circuits, epoxy castables, potting materials, and other chemical fields.

  • Application fields of spherical silica powder products

Low oil absorption, mixed viscosity and friction coefficient, easy to disperse, uniform mixing, can significantly increase the fluidity of materials, commonly used in VLSI plastic packaging materials, VLSI, fine chemicals, rewritable CDs and large areas Electronic substrates, special ceramics and special rubber, aviation, aerospace engineering, etc.

With the development of the high-tech industry, silicon micro-powder has become more widely used and used more and more, which has great market demand and potential. The rapid development of the microelectronics industry has put forward higher and higher requirements for silicon micropowder. Silicon micropowder not only needs to be ultra-fine, high-purity, and low-radioactive element content, but also spheroidizes the particle shape. For the huge market demand in the future, it is necessary to improve the quality of silicon raw materials, improve the technical level of silicon powder production, and strengthen the testing and control of the production process, so as to improve the quality of silicon powder products.

 

Article source: China Powder Network