Silicon for aluminum alloying

Silicon is commonly used as an alloying element in aluminum, both in high quantities (up to 10–12%, and in even higher in some cases) and in low quantities to adjust the properties of the final aluminum alloy. Silicon gives the alloy the properties needed during processing and its intended end-use within as diverse sectors as transportation, construction, engineering and consumer durables.

Understanding the role of silicon in aluminium alloying 

As a critical alloying element, silicon enhances the strength, durability, and heat resistance of aluminum-based materials.

When used in larger amounts, silicon also strongly reduces the melting temperature and increases fluidity and castability of the aluminium alloy, essential for die casting operations. Adding silicon to aluminium is essential for high-pressure die-casting operations, as it strongly reduces the melting temperature and increases fluidity and castability of the alloy. Silicon also makes materials lighter (because of its lower density compared to aluminium), improving cost-effectiveness and fuel-efficiency in transport applications.

Elkem is a dependable supplier of consistently high-quality silicon for aluminium alloying. In addition to the regular silicon products for alloying (as for example our 3003 and 4010 products), we also supply SiLLOY™, which is an excellent alternative for applications not requiring silicon with very low iron content.

For any quality you order from us, we will deliver an alloying material that will meet or exceed your expectations.  

Comprehensive silicon grades 

Today we supply nearly all metallurgical silicon grades normally used for alloying – some examples (but far from all) can be seen in our metallurgical silicon product data sheet.

With a focus on stable and high-quality raw materials, strong process control and a strict focus on quality, we also supply our unique SiLLOY™ brand, which are purpose-made products with slightly higher and controlled iron content, and low content of (for example) calcium and phosphorus.

SiLLOY™ is an excellent choice if very low iron is not needed for your application. SiLLOY™ finds use in both primary and secondary smelters, often within production processes for sheet ingots, but also other products – including high-silicon foundry materials. It can also be noted that for certain products, iron is purposely added in large amounts to the alloy (using, for example, our 4019 and 8022 products, which contain 5-6% iron). Examples of SiLLOY™ products can be seen in our SiLLOY Product Data Sheet.

Elkem has been delivering silicon to the aluminium industry for several decades, and our versatile and still developing silicon product portfolio serves both the primary and secondary aluminium industries. Of particular note are products for aluminium foundry alloys (including high-pressure die-casting applications), specifically the 3xx.x and 4xx.x series and the 4000 and 6000 series, which are mainly for aluminium ingots.

Elkem uses Norwegian hydropower and today produces materials with low GHG emissions. We are also committed to further reducing our emissions and to be carbon-neutral by 2050 (see our sustainability pages).

Please contact us if you have any questions or requests regarding silicon materials for aluminium production – together we will find a solution tailored to your needs.