What are the main characteristics of zirconia nozzles?

High Temperature Resistance: With a melting point of 2715°C, zirconia withstands prolonged erosion by molten steel exceeding 1600°C. It exhibits strong inertness toward elements like oxygen and sulfur in molten steel, resisting erosion and spalling.

Excellent Thermal Shock Resistance: Features a low and uniform thermal expansion coefficient. Resists cracking or fracture during rapid thermal cycling in continuous casting operations, extending service life by 30%-50% compared to conventional aluminum-carbon nozzles.

Strong Chemical Stability: Does not react chemically with molten steel or slag, preventing impurity introduction into the steel melt. Effectively safeguards billet purity and reduces inclusion defects.

Smooth surface with low flow resistance: The inner wall remains flat and smooth after forming, minimizing resistance to molten steel flow. This stabilizes the flow field, prevents slag entrapment or flow deviation, and enhances slab surface quality and dimensional accuracy.

Suitable for high-demand steel grades: Particularly suitable for continuous casting of steel grades with extremely high purity and surface quality requirements, such as stainless steel, bearing steel, gear steel, and electrical steel.

Adaptable to harsh operating conditions: Maintains stable performance in high-intensity production scenarios like multi-furnace continuous casting and high-speed continuous casting, reducing nozzle replacement frequency and enhancing production continuity.

Higher Cost: Zirconia raw materials are expensive, making finished nozzles 2-3 times more costly than conventional aluminum-carbon nozzles. Primarily used in high-end steel production.

Complex Forming Process: Requires precision manufacturing techniques such as isostatic pressing and high-temperature sintering, demanding advanced production equipment and technology.