Ceramic bearings wear mechanisms

Oxide ceramics exhibit superior mechanical properties, corrosion and wear resistance. Since the oxides are the highest oxidation state of the metal, they are stable even in the most invasive industrial and biomedical environments. Alumina and zirconia are utilized as load-bearing hard tissue replacements and fixation implants in dentistry and surgery. 

Historical review of tribological studies of metallic and ceramic bearing surfaces used for total hip arthroplasty (THA). Presents an objective assessment of wear mechanisms, wear measurement, laboratory studies, and clinical observations for THA. 

In this section, we outline the history of ceramics in orthopedics and provide an introductory overview of ceramic materials relevant to hip replacement. This section also discusses the use of ceramic femoral heads as bearing surfaces with UHMWPE and covers current designs of ceramic-on-ceramic (COC) alternative bearings. The final part of this section contains an overview of wear mechanisms and ceramic fracture risk in historical, as well as in current, ceramic materials. 

The importance of fluid-film lubrication mechanisms experienced in hip implants is reviewed. For the different types of hip implants curraitly used in clinical practice, including conventional/cross-linked polyethylaie-on-metal/ceramic, metal-on-metal and ceramic-on-ceramic bearing couples, a detailed review is presented of theoretical fluid-film lulaicatiOT analyses along with friction measurements and wear studies, both having a strong emphasis on the fluid-film mechanisms involved. Future studies and improvements of hip implants from a fluid-film luMcation point of view are discussed. 

Wear-resistant materials Mechanical seal, ceramic liner, bearings. 

Another noteworthy effort at nanocomposite fabrication applied ceramic nanoparticles to a ceramic material to enhance osteoconductivity and mechanical performance. Nawa et al. [49] developed a ceria-stabiHzed tetragonal zirconia polycrystal (Ce-TZP) ceramic and incorporated alumina (AI2O3) nanocrystals into it via wet chemistry methods for load-bearing bone applications. Further studies of this material investigated its ability to induce apatite formation [50], in vivo biocompatibility, and resistance to wear [10] with favorable results. 

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