What is the difference between zirconia ceramics and alumina ceramics?

Zirconia ceramics and alumina ceramics are two widely used ceramic materials. So, what are the differences between zirconia ceramics and alumina ceramics? Let’s analyze it for you below.

1. Introduction and Applications of Alumina Ceramics

1.1 Introduction

Alumina ceramics are ceramic materials primarily composed of aluminum oxide (Al2O3) and are used in thick-film integrated circuits. Alumina ceramics exhibit excellent conductivity, mechanical strength, and high-temperature resistance. It’s important to note that they require cleaning with ultrasound. Alumina ceramics are widely used due to their superior properties, meeting the needs of both everyday and specialized applications in modern society.

1.2 Applications

There are two main types of alumina ceramics: high-purity and regular. High-purity alumina ceramics have an Al2O3 content of over 99.9%. Due to their high sintering temperature ranging from 1650 to 1990°C and a transmission wavelength of 1 to 6 μm, they are often used to make fused glass to replace platinum crucibles. Their transparency and resistance to alkali metal corrosion make them suitable for sodium lamp tubes. In the electronics industry, they are used as integrated circuit substrates and high-frequency insulation materials.

2. Introduction and Applications of Zirconia Ceramics

2.1 Introduction

Zirconia ceramics, or ZrO2 ceramics, possess excellent properties such as high melting and boiling points, high hardness, insulation at room temperature, and conductivity at high temperatures. Pure ZrO2 is white, but it appears yellow or gray in the presence of impurities, often containing HfO2, which is challenging to separate. There are approximately 19 million tons of confirmed zirconium resources worldwide, and zirconia is typically purified from zircon minerals.

At normal pressure, pure ZrO2 has three crystalline phases: monoclinic zirconia, tetragonal zirconia, and cubic zirconia. These phases exist within different temperature ranges and can transform into one another:

(1) Monoclinic zirconia: Temperature < 950°C, density 5.65 g/cc.
(2) Tetragonal zirconia: Temperature 1200-2370°C, density 6.10 g/cc.
(3) Cubic zirconia: Temperature > 2370°C, density 6.27 g/cc.

2.2 Applications

Due to its high toughness, high flexural strength, excellent wear resistance, outstanding thermal insulation properties, and a thermal expansion coefficient close to that of steel, zirconia ceramics find extensive applications in structural ceramic fields. Some of the main uses include Y-TZP grinding balls, dispersing and grinding media, nozzles, ball valve seats, zirconia molds, micro-fan shafts, fiber optic pins, fiber optic sleeves, drawing dies, cutting tools, clothing buttons, watch cases and straps, bracelets and pendants, ball bearings, lightweight golf club heads, and other room-temperature wear-resistant components.

3. A Comparison Between Zirconia Ceramics and Alumina Ceramics

In comparison, zirconia ceramics are more wear-resistant than alumina ceramics. This is because zirconia ceramics have a higher sintering temperature and a density that is twice as high as alumina ceramics.

The above analysis provides a comparison between zirconia ceramics and alumina ceramics, as presented by Jin Gong Precision Zirconia Ceramics Factory. We hope this information serves as a useful reference for you.

Contact us