​1. Chemical Composition & Key Differences​​

The primary distinctions between FeSi45 and FeSi65 lie in their ​​silicon content​​ and ​​impurity levels​​:

• ​​FeSi45​​:
  • ​​Silicon Content​​: 45–47%
  • ​​Iron (Fe)​​: 53–55%
  • ​​Impurities​​: Higher levels of aluminum (≤2%), calcium (≤1.5%), and carbon (≤0.3%) due to lower silicon purity .
  • ​​Physical Properties​​: Gray granules or lumps with moderate bulk density.
• ​​FeSi65​​:
  • ​​Silicon Content​​: 65–72%
  • ​​Iron (Fe)​​: 30–35%
  • ​​Impurities​​: Stricter control (Al ≤0.5%, Ca ≤0.5%, C ≤0.2%) for enhanced performance .
  • ​​Physical Properties​​: Dark gray, compact lumps with higher thermal stability.

Contrast​​:

FeSi45 is a ​​cost-effective option​​ for general-purpose applications, while FeSi65 offers ​​superior deoxidation efficiency​​ and alloying flexibility for high-performance demands.

​​2. Applications​​

​​Ferro Silicon 45​​

• ​​Basic Steelmaking​​: Used for deoxidizing low-carbon steels and structural alloys.
• ​​Foundry Cast Iron​​: Improves wear resistance in gray cast iron by controlling graphite morphology .
• ​​Cost-Sensitive Projects​​: Ideal for large-scale applications where moderate silicon content suffices.

​​Ferro Silicon 65​​

• ​​High-Grade Steels​​: Enhances strength and hardness in spring steel, bearing steel, and electrical silicon steel .
• ​​Ductile Iron Production​​: Promotes graphite spheroidization, replacing brittle carbides for ductile cast iron.
• ​​Heat-Resistant Alloys​​: Supports thermal stability in extreme environments.
• ​​Specialized Uses​​: Acts as a reducing agent in ferroalloy production and welding electrode coatings .