company news about How to Improve SiC Roller Life in NCM Production？

In NCM (Nickel Cobalt Manganese) cathode material production, SiC rollers are exposed to highly aggressive environments involving LiOH, high temperatures, and oxidizing atmospheres.

Silicon carbide ceramic materials overview

Under these conditions, roller lifetime can drop significantly, sometimes from ~2 years (LFP conditions) to ~2 months in NCM processes.

Improving SiC roller service life requires a combination of material optimization, process control, and surface engineering.

Why SiC Rollers Fail in NCM Production

Key Operating Conditions

• Lithium source: LiOH
• Temperature-critical zone: 700–800°C
• Atmosphere: Oxidizing + corrosive gases

1. Chemical Corrosion

SiC reacts with oxygen and forms a SiO₂ protective layer. However, in NCM systems:

• LiOH decomposes and generates reactive lithium species
• SiO₂ reacts with lithium compounds → Li₂SiO₃
• At 700–800°C, lithium silicates soften and form molten phases

 This leads to continuous dissolution of the protective layer.

2. Molten Salt Attack

Liquid lithium compounds:

• Penetrate into surface defects
• Accelerate corrosion reactions
• Destroy surface stability over time

3. Microstructural Degradation

Typical degradation behavior includes:

• Density drop: ≥ 3.05 g/cm³ → ~2.8 g/cm³
• Increased porosity
• Grain boundary weakening

Result: structural instability and roller fracture risk.

Key Strategies to Improve SiC Roller Life

1. Surface Coating Protection (Short-Term Solution)

Recommended coatings:

• Y₂O₃ / Al₂O₃ rare-earth coatings
• Applied via plasma spraying

Function:

• Prevent molten salt wetting
• Block corrosive gas penetration
• Delay chemical attack

Effective for rapid improvement of existing production lines.

2. CVD SiC Coating (Long-Term Solution)

For higher durability requirements, SiC roller substrates can be upgraded with engineered solutions:

SiC kiln roller solution

Process:

• Chemical Vapor Deposition (CVD) SiC coating
• Forms a dense, high-purity protective layer

Advantages:

• Near-zero porosity surface
• Strong substrate bonding
• Excellent chemical stability
• Blocks molten lithium penetration

Suitable for continuous, high-load industrial operation.

3. Optimize Critical Temperature Zone

Why 700–800°C matters:

• Lithium silicates become unstable
• Molten phases accelerate corrosion

Recommended actions:

• Reduce residence time in this zone
• Stabilize furnace temperature fluctuations
• Control heating rate precisely

Reduces chemical attack intensity.

4. Material Selection and Quality Control

Key SiC requirements:

• Density ≥ 3.05 g/cm³
• Open porosity ≈ 0
• High purity SiC (≥ 98.5%)

Material quality directly determines:

• Penetration resistance
• Chemical stability
• Service lifetime

5. Monitoring and Preventive Maintenance

Recommended monitoring:

• Density variation tracking
• Surface inspection (spalling / cracks)
• Dimensional stability checks

Maintenance strategy:

• Replace rollers before severe degradation
• Correlate service life with process conditions

Comparison of Improvement Approaches

Conclusion

Improving SiC roller life in NCM production requires addressing:

• Chemical corrosion (LiOH + SiO₂ reaction)
• Molten phase formation at 700–800°C
• Microstructural degradation

Effective solutions include:

• Surface coatings for quick improvement
• CVD SiC layers for long-term stability
• Process optimization to reduce corrosive conditions

Key Takeaway

For NCM cathode production:

Surface engineering + process control + material quality = extended SiC roller life

Need Technical Support for SiC Rollers?

Providing the following helps optimize performance:

• Furnace temperature profile
• Lithium source (LiOH / Li₂CO₃)
• Roller dimensions and loading conditions
• Target service life

SiC thermocouple protection tube

Customized engineering solutions can significantly reduce failure rates and operating costs.