Characteristics and Applications of Zirconia Ceramics

Zirconia ceramic (ZrO ₂) is a high-performance ceramic material mainly composed of zirconium and oxygen. Due to its excellent fracture toughness, high hardness, wear resistance, and biocompatibility, it is highly favored in the industrial, medical, and electronic fields. 

1、What is zirconia ceramic?

Zirconia Ceramic is a type of phase transition toughened ceramic, whose unique crystal structure enables it to undergo martensitic transformation under stress, thereby absorbing energy and preventing crack propagation. This characteristic gives it higher impact resistance than alumina ceramics (fracture toughness can reach 8-10 MPa · m ²).

Zirconia ceramics are typically stabilized with yttrium oxide (Y ₂ O ∝) to form 3Y-TZP (tetragonal zirconia), ensuring its metastability at room temperature. 

Common preparation processes include:

Dry pressing and sintering

Hot isostatic pressing (HIP)

Injection molding (suitable for complex shapes)

2. Classification of zirconia ceramics

According to the different stabilizers and microstructures, zirconia ceramics are mainly divided into:

Fully stable zirconia (FSZ): cubic phase structure, high temperature resistance but low toughness

Partially stabilized zirconia (PSZ): a mixed phase structure that combines strength and toughness

Tetragonal zirconia (TZP): 3Y-TZP (yttrium stabilized), Ce TZP (cerium stabilized)

3. Characteristics of zirconia ceramics

High fracture toughness (8-10 MPa · m ²), far exceeding alumina (3-4 MPa · m ²)

Excellent wear resistance (hardness Hv1.200-1400), suitable for high friction environments

Low thermal conductivity (2-3 W/m · K), suitable for insulation applications

Biocompatibility (non-toxic, does not cause rejection reactions)

Corrosion resistance (acid and alkali resistance, except hydrofluoric acid)

4. Application of zirconia ceramics

(1) Industrial sector

Ceramic bearings (non-magnetic, corrosion-resistant, used for precision instruments)

Mechanical sealing rings (chemical pumps, compressors, with a lifespan of over 8000 hours)

Cutting tools (for machining high hardness alloys)

(2) Medical field

Dental implants (all ceramic crowns, implant abutments)

Artificial joints (hip and knee prostheses)

(3) Electronics and Consumer Goods

Oxygen sensor (automotive exhaust detection)

Smartphone Backboard (with excellent 5G signal penetration)

High end cutting tools (lightweight, never rusting)

5、Summary

Zirconia ceramics have become an ideal material for high-end industrial and medical applications due to their high toughness, wear resistance, and biocompatibility. With the development of nanotechnology and 3D printing technology, its performance and application scope are still constantly expanding.