ZTC: partially stabilized ZrO₂ ceramics with high TiC-content

Advanced zirconia composites with high microscopic wear resistance and hydrothermal stability

Pressureless sintered or hot-isostatically pressed zirconia ceramics with high carbide content are characterized by a microstructure with all grains in the submicrometer range and with grain boundaries that are free of any amorphous films. Unique compositions and technological approaches are developed to meet special requirements in technical applications and are used to produce individual prototypes and small series.

Advantages

The material unites the advantages of well-known yttria stabilized ZrO₂ - ceramics as a high strength and an extremely fine-grained microstructure with:

• a significantly improved hardness and wear resistance (e.g. wear rate of ZrO₂/TiC against Al₂O₃ in dry air is 1/10 of the wear rate of Y-TZP with the same grain size)
• doubled thermal conductivity
• enhanced mechanical and hydrothermal aging resistance because of reduced subcritical crack-growth (e.g. constant strength and hardness after 140 hours at 220 °C/H₂O

The good electroerosive processability of this material provides additional advantages for the production of parts made of this material. Another important merit of the developed technology is the possibility to achieve improved properties without expensive hot pressing.

Application

• Ceramic knives for the medical applications (microtomes), for machines in the paper and textile industry, and for equipments in the processing of viscous masses
• Sliding head substrates in data storage systems
• High precision wear-resistant parts (e.g. ball bearings, chucks for the automatic change of tools)
• Substitution of ZrO₂ to enable advantageous electroerosive processing of parts
   

Properties given for ZrO₂ + 35vol-% TiC (+ Al₂O₃)