The Core Difference between 99 and 99.5 Alumina Ceramics

The core difference between 99% and 99.5% alumina ceramics lies in their purity. This 0.5% difference leads to a huge gap in their performance and applications.

Leap in Performance

The increase in purity directly translates into qualitative changes in three key properties:

1. Electrical Insulation: Impurities are the culprit of current leakage. 99.5% ceramics have fewer internal defects, so their insulation strength and volume resistivity far exceed those of 99% ceramics, making them suitable for high-voltage and high-frequency scenarios.

2. Mechanical Strength: Impurities weaken the bonding force between grains. 99.5% ceramics have a denser and more uniform structure, with significantly improved hardness and flexural strength, making them more wear-resistant and pressure-resistant.

3. Chemical Stability: Impurities are the breakthrough point for chemical corrosion. Thus, 99.5% ceramics have much better corrosion resistance.

Divergence in Applications

Performance differences determine their application boundaries:

99% Ceramics: They are cost-effective and widely used in conventional industrial fields such as mechanical seals and wear-resistant components.

99.5% Ceramics: They are positioned in the high-end market and serve as key materials for integrated circuit substrates, semiconductor components, high-performance bearings, and medical implants.

Conclusion

This 0.5% difference in purity is a technical threshold that distinguishes "industrial-grade" from "electronic-grade/high-performance-grade" ceramics, reflecting a precise trade-off between cost and ultimate performance.