Fracture Toughness of 3Y-TZP Dental Ceramics by Using Vickers Indentation Fracture and SELNB Methods

  • Moradkhani, Alireza (Art & Architecture Faculty, Yadegar-e Imam Khomeini (RAH) Shahre-Rey Branch, Islamic Azad University) ;
  • Baharvandi, Hamidreza (Faculty of Materials & Manufacturing Processes, Malek-Ashtar University of Technology) ;
  • Naserifar, Ali (Art & Architecture Faculty, Yadegar-e Imam Khomeini (RAH) Shahre-Rey Branch, Islamic Azad University)
  • Received : 2018.05.17
  • Accepted : 2018.08.17
  • Published : 2019.01.31


The objective of this research is to analyze the fracture toughness of pure and silica co-doped yttria-stabilized tetragonal zirconia polycrystal (3Y-TZP) bioceramics containing 0.1 and 0.2 wt.% of alumina, and sintered at a temperature of $1500^{\circ}C$. Because of the relatively easy preparation of the test specimens and the high speed of testing, the Vickers indentation fracture (VIF) technique is more frequently used to evaluate the fracture toughness of biomaterials and hard biological tissues. The Young's modulus and hardness values were obtained by means of nanoindentation and indentation methods. The fracture toughness values of 3Y-TZP bioceramics were calculated and analyzed using 15 equations related to the VIF technique, and loadings of 49.03 and 196.13 N with a Vickers diamond. For validation, the results were compared with fracture toughness values obtained by the single-edge laser-notch beam (SELNB) method with an almost atomically sharp laser-machined initial notch.


Zirconia;Fracture toughness;Dental materials;Bioceramics


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