What is Silicon Calcium Cored Wire？

Calcium silicon cored wire is a specialized metallurgical material designed specifically for molten steel refining. It consists of a low-carbon steel strip (0.3-0.5 mm thick) sheathed with a core filled with high purity calcium silicon alloy powder. This alloy powder typically contains 55-65% silicon (Si), 15-25% calcium (Ca), and trace elements. Impurity levels such as phosphorus (P) and sulfur (S) are strictly controlled below 0.05%. Its unique structure enables precise delivery of active elements deep into the molten steel, preventing oxidation losses during the addition process and addressing the bottleneck of low element recovery in traditional alloy block addition.

Chemical Composition:

Ca ≥ 15%, Si ≥ 55%, P ≤ 0.04%, S ≤ 0.05% (core powder complies with GB/T 4138 standard)

Physical Properties:

Diameter: φ9/13/16mm (±0.2mm tolerance); Filling Rate: 85-95%; Number of Joints ≤ 2/km

Mechanical Strength:

Bends 90° around a mandrel 20 times its diameter without cracking; Passes 0.5MPa water pressure test
Appearance: No powder leakage, smooth weld, surface roughness Ra < 1.6μm

1. Higher Element Utilization and Refining Efficiency

Excellent Recovery Rate:

The sealed steel jacket isolates calcium and silicon from air and slag, increasing calcium recovery to 45-55%-20-30% higher than alloy block (≤ 30%) and 15% higher than open powder injection. This means that one ton of calcium silicon alloy wire has the same deoxidation effect as 1.3 tons of conventional alloy, directly reducing material consumption.

Uniform Element Distribution:

CaSi cored wire is fed into the molten steel at a depth of 1.5-2.5 meters using specialized equipment to prevent surface oxidation and ensure uniform element distribution. Tests show that the oxygen content in the steel changes by ≤3 ppm after treatment, while the change after adding alloy ingots is 8-12 ppm.

2. High Efficiency and Energy Saving

Reduced Total Refining Cost:

Although the unit price is slightly higher than alloy ingots, the element recovery rate is increased by 20-30%, reducing the overall material cost by 15-20%. A 100-ton ladle refining process can save approximately $200-300 per batch.

Reduced Secondary Waste:

Spherical inclusions generated by the reaction are easily removed, reducing slag generation by 10-15% and lowering slag disposal costs. No dust leakage during the charging process also reduces environmental protection costs.

3. Strong Adaptability and Wide Range of Applications

Compatible with various scenarios:

Compatible with converter, electric furnace, and LF ladle refining processes, it is suitable for the production of carbon steel, alloy steel, and high-purity specialty steel. High-purity grades even meet the stringent requirements of automotive bearing steel (oxygen content ≤ 15ppm).

Customizable Specifications:

Supports custom diameters (φ8-φ20mm) and adjustable core powder ratios (for example, low-silicon Ca30Si35 for automotive steel sheets), eliminating the "one-size-fits-all" problem of traditional materials.

4. Environmental Safety

Low Emissions:

The sealed sheath design reduces dust emissions by over 30% compared to open powder feeding, meeting the steel industry's "ultra-low emission" standards.

Safe Powder Feeding:

Workers are protected from direct contact with high-temperature molten steel, reducing the risk of burns and dust inhalation. The stable mechanical structure also prevents wire breakage during powder feeding.

The refining process relies on three core mechanisms to improve steel quality:

Deep Deoxidation:

Calcium and silicon react with oxygen in the molten steel to form stable CaO·SiO₂ inclusions, which are easily removed by floating, reducing the oxygen content in the steel to ≤ 20ppm.

Inclusion Modification:

Converts harmful, elongated sulfide inclusions into spherical calcium sulfide (CaS), improving the toughness and workability of the steel.

Enhanced Desulfurization:

Calcium reacts with sulfur to form insoluble CaS, reducing the sulfur content in the steel to <0.005% while maintaining the steel's strength. High-purity steel production.

Compared to traditional alloy lumps, element recovery is increased by 20-30% (calcium recovery reaches 45-55%), significantly reducing production costs.

Matching the Grade to the Steel Type: Choose Ca28Si60 for common steel and high-purity grades for specialty steel.

Verifying Supplier Qualification: Prioritize manufacturers with automated production lines (qualification rate ≥ 98%) and third-party inspection reports.

Inspecting Physical Integrity: Check for defects such as powder leakage, uneven diameter, or rough welds, which can reduce refining efficiency.