In the alchemy of modern steelmaking, one unassuming yet vital material stands out: cored wire. Functioning like a tailor-made "precision medicine" for molten steel, it delivers targeted metallurgical benefits through efficient, controlled, and highly effective treatment, ultimately endowing steel with superior mechanical and processing properties. Among all products, Calcium Silicon Cored Wire (CaSi Cored Wire) stands out as the most widely used and effective.
Cored Wire: A Precision Metallurgical Carrier
Cored wire is a composite linear material consisting of a steel strip sheath enclosing a core of functional powder. Its ingenious structure enables precise delivery of reactive elements deep into the molten steel bath.
Core Components:
Sheath (Steel Strip): Typically low-carbon steel strip, 0.3–0.4 mm thick. It protects the core powder, provides mechanical strength during feeding, and ensures the powder reaches the desired depth in the molten steel.
Core Powder: A precisely formulated mixture of metallurgical powders such as alloying agents (e.g., CaSi, CaFe, FeB), deoxidizers, or specialty elements.
Form: Supplied in coils and fed continuously into ladles or tundishes using automated wire-feeding machines.
Main Classifications of Cored Wire
Based on the type of core material, cored wires can be divided into the following categories:
Alloy Cored Wire
Examples: Calcium Silicon Cored Wire (CaSi), Calcium Iron Cored Wire (CaFe), Aluminum Cored Wire (Al), Silicon Barium Cored Wire (SiBa).
Primary functions: deoxidation, desulfurization, and alloy element addition in molten steel.
Pure Calcium Cored Wire (Ca)
Mainly applied in deep desulfurization and modification treatment, effectively improving the morphology of inclusions in steel.
Carbon Cored Wire
Example: Graphitized Carbon Cored Wire, used to adjust carbon content in molten iron or molten steel.
Functional Cored Wire
Contains special elements such as rare earths, titanium, and boron, which are used to optimize microstructure and impart special properties to steel.
Key Advantages
?Precise Composition Control
Feeding speed and length are precisely controlled, enabling gram-level accuracy in alloy addition—essential for high-end steel grades with tight compositional tolerances.
?Efficient Deoxidation and Desulfurization
Core powders (e.g., Al, Ca, Mg) react rapidly at depth in the molten steel, achieving significantly higher deoxidation efficiency and desulfuriz
The rate than the surface addition. This reduces [O] and [S] to ultra-low levels, promoting clean steel production.
?Inclusion Engineering (Inclusion Modification)
This is the most advanced application. By introducing calcium (Ca), cored wire transforms harmful, high-melting-point Al?O? clusters into low-melting-point, spherical calcium aluminates. This inclusion modification prevents nozzle clogging and enhances steel ductility and fatigue resistance.
?Improved Steel Fluidity
Modified inclusions flow more easily and are less likely to aggregate, significantly reducing the risk of nozzle clogging during continuous casting and ensuring stable casting operations.
?Enhanced Steel Performance
Through improved steel cleanliness, optimized inclusion morphology, and microalloying effects, cored wire contributes to:
- Higher toughness and ductility
- Improved fatigue strength
- Better weldability and corrosion resistance
- Superior cold workability
?Process Safety & Environmental Benefits
Eliminates the splashing, dust, and fumes associated with bulk alloy addition, improving workplace safety and reducing environmental emissions.
CaSi Cored Wire: The Key Performer
Typical Composition
Ca: 28–35%
Si: 55–65%
Fe as balance
Core Functions
Strong deoxidizer & desulfurizer: Ca forms CaO & CaS; Si enhances oxygen removal.
Steel purification: Inclusion modification and control.
Performance improvement: Boosts toughness, plasticity, fatigue strength, and impact resistance.
Applications
Essential in clean steel, low-sulfur steel, high-grade alloy steels.
Widely used in shipbuilding steel, pipeline steel, bearing steel, and spring steel.
Technical & Economic Advantages
High element recovery rates for Ca and Si.
Precise alloy delivery via controlled wire feeding.
Reduced dust, splashing, and operator risk.
Lower cost through efficient alloy use and reduced rework.
Conclusion
Cored wire, particularly CaSi Cored Wire, has revolutionized modern steel refining by transforming how alloying and purification are performed. As a precision metallurgical tool, it enables unprecedented control over steel cleanliness, inclusion morphology, and final product performance.