What's the specific gravity of ferro silicon
Nov 07, 2025
I. The Nature of Ferrosilicon's Specific Gravity
Ferrosilicon is an alloy of silicon and iron, and its specific gravity typically fluctuates between 3.5 and 3.8 g/cm³. This value is like the alloy's "body mass index," changing with the silicon content-silicon atoms are lighter than iron atoms, so a higher silicon content actually results in a slightly lower overall specific gravity. Interestingly, liquid ferrosilicon is about 5% lighter than its solid state, a phenomenon similar to the shrinking volume of ice when it melts, a fascinating aspect of physics.
II. The Special Characteristics of 72% Ferrosilicon
72% ferrosilicon specifically refers to a type with a silicon content of approximately 72%, and its specific gravity is consistently around 3.5 g/cm³. This alloy acts like a "universal seasoning" in the metallurgical field:
Steelmaking deoxidation: Its moderate specific gravity allows for uniform distribution in molten steel.
Alloy additives: Precise ferrosilicon ratios can control the properties of finished steel.
Casting improvement: A suitable specific gravity prevents compositional segregation in castings.
III. Three Major Factors Affecting Specific Gravity
Besides silicon content, these factors cause subtle changes in the "weight" of ferrosilicon:
Porosity: A sponge-like porous structure reduces the measured specific gravity.
Impurity type: Impurities such as manganese and chromium increase specific gravity.
Temperature: Specific gravity decreases by approximately 0.5% for every 100°C increase.
In practical use, it is recommended to verify the specific gravity characteristics of a particular batch through sedimentation tests, which is crucial for ensuring metallurgical effectiveness.
Currently, we have gray-black ferrosilicon raw materials in stock, with a silicon content exceeding 75%, packaged in moisture-proof ton bags, and sold by actual weight. This high-silicon type has a specific gravity of approximately 3.4 g/cm³, good fluidity, and is particularly suitable for casting scenarios requiring precise composition control.
If you are interested in our ferro silicon, please don't hesitate to contact us. Our email: info@kexingui.com
