Which is better, zirconia ceramics or alumina ceramics?

Zirconia ceramics and alumina ceramics are two popular ceramic materials in the industrial field. Each of them has its own advantages and disadvantages. But which one has better performance? Through a comparison in five aspects, we will help you make a judgment.

Density contrast

The density of zirconia ceramic structural components is higher than that of alumina ceramics. Its density is 6, and it has a finer texture and better precision processing performance. In contrast, the density of alumina ceramics is 3.5, which is relatively lower.

Comparison of Ceramic Toughness

The toughness of zirconia ceramics is four times that of alumina ceramics, and it has better impact resistance. When dropped freely from a one-meter height, zirconia ceramics will only have some cracks, while alumina will break.

Density Comparison

The density of zirconia ceramics is twice that of alumina ceramics. Therefore, in comparison, zirconia has better compressive strength and can withstand greater pressure.

Comparison of Friction Coefficients

The friction coefficient of zirconia ceramics is only half that of alumina ceramics. Although the friction coefficient of alumina ceramics is already very low, in actual use, elastic wear and hard wear should also be taken into consideration. Which material can withstand wear depends on the specific usage situation.

Comparison of surface smoothness

The surface finish of the zirconia ceramic structural components is much higher, presenting a mirror-like appearance and being extremely smooth. The friction between them and the net is much smaller, which can further extend the service life of the net, significantly reduce net consumption, lower the current in the paper net section, and decrease electricity consumption.

Zirconia ceramics vs. Alumina ceramics: What are the differences?

Zirconia ceramics, with their outstanding toughness and wear resistance, have become the preferred choice for semiconductor cutting tools. While alumina ceramics dominate in the etching equipment market due to their cost advantages. Both have their own strengths in terms of density, hardness and processing difficulty. The choice depends on the balance between performance requirements and budget.

I. Material Characteristics Differences

(1) Hardness and Wear Resistance

The Mohs hardness of zirconia ceramics can reach 8.5 - 9 levels, while the Mohs hardness of alumina ceramics is generally around 9 levels. From the data, alumina ceramics seem to have an edge, but in practical applications, zirconia ceramics, with its unique microstructure, performs better in terms of wear resistance. In the semiconductor chip manufacturing process, the wafers need to undergo repeated cutting, grinding, and other operations. The cutting tools and grinding discs made of zirconia ceramics can maintain the sharpness of the blade and the flatness of the disc surface during long-term high-speed operation, effectively reducing the damage to the wafers and improving processing accuracy and product yield. In contrast, the cutting tools made of alumina ceramics wear out relatively faster under the same conditions, requiring more frequent replacement of the tools, which not only increases production costs but may also affect production efficiency.

(2) Density

The density of zirconia ceramics is relatively high, approximately 6g/cm³, while the density of alumina ceramics ranges from 3.7 to 3.95g/cm³. This density difference gives zirconia ceramics an advantage in some applications where quality requirements are high. When manufacturing high-precision components for semiconductor equipment, such as mirrors and lens supports in lithography machines, the high density of zirconia ceramics can provide better stability and shock resistance, ensuring that the components do not shift due to vibration during high-speed operation and high-precision operation of the equipment, thereby guaranteeing the accuracy and reliability of the equipment.

(3) Toughness

Zirconia ceramics possess remarkable toughness, with their fracture toughness typically ranging from 6 to 8 MPa·m¹/². This property enables them to effectively absorb energy when subjected to external forces, thereby preventing brittle fractures. In the daily use of semiconductor equipment, components are inevitably exposed to various minor impacts and vibrations. Components made of zirconia ceramics can better withstand these external forces, reducing the risk of damage. For instance, in semiconductor etching equipment, zirconia ceramic reaction chambers can maintain structural integrity under frequent plasma impacts, prolonging the equipment's service life. In contrast, the fracture toughness of alumina ceramics is lower, typically ranging from 3 to 4 MPa·m¹/². When facing the same impact, they are more prone to develop cracks or even fracture, affecting the normal operation of the equipment.

III. Processing Difficulty and Cost Considerations

(1) Processing Difficulty

Since both zirconia ceramics and alumina ceramics have the characteristics of high hardness and brittleness, their processing difficulties are relatively large. However, there are also certain differences between them. Due to its higher toughness, zirconia ceramics have relatively less wear on the cutting tools during the processing. However, because of its poor thermal conductivity, the heat generated during the processing is difficult to dissipate, which easily leads to thermal deformation of the workpiece. Therefore, the processing technology and equipment requirements are more stringent. When processing zirconia ceramic threads, a high-precision ceramic milling machine is required, along with an advanced cooling system and tool compensation function, to ensure processing accuracy and quality. While alumina ceramics have higher hardness, their toughness is relatively lower. During the processing, cracks and chipping are more likely to occur. When processing thin-walled parts of alumina ceramics, the cutting parameters and tool paths need to be strictly controlled to avoid the parts from cracking during the processing.

(2) Cost

From a cost perspective, alumina ceramics have significant advantages. Their raw material sources are diverse, and the preparation process is relatively mature, resulting in a relatively lower price for alumina ceramics. In large-scale industrial applications, such as wear-resistant linings for ordinary semiconductor equipment and sandblasting nozzles, alumina ceramics, due to their cost advantage, become the preferred material. However, zirconia ceramics, due to their higher raw material costs and complex preparation process, typically have a price that is 2-3 times that of alumina ceramics. In some cost-sensitive application scenarios, the high cost of zirconia ceramics may limit its application scope. But in highly demanding high-end fields, such as aerospace and high-end medical equipment, zirconia ceramics' excellent performance makes it an indispensable material, and the cost factor can often be offset by its performance advantages.

By comparing in terms of density, toughness, porosity, friction coefficient, and surface finish, we can observe that zirconia ceramics exhibit superior performance in these aspects compared to alumina ceramics. However, the specific choice of material still needs to be determined based on actual usage requirements and cost considerations.