Mechanical behavior of yttria-stabilized tetragonal zirconia polycrystalline ceramic after different zirconia surface treatments

• Published in: Materials Science & Engineering C 2017-08, Vol.77, p.828-835
• Main Authors: Pozzobon, Joao Luiz, Pereira, Gabriel Kalil Rocha, Wandscher, Vinicius Felipe, Dorneles, Lucio Strazzabosco, Valandro, Luiz Felipe
• Format: Article
• Language: English
• Subjects: Aluminum; Aluminum oxide; Analysis; Ceramics; Damage; Dental health; Etching; Flexing; Flexural strength; Genetic transformation; Hydrofluoric acid; Materials science; Materials Testing; Mechanical properties; Microscopy, Electron, Scanning; Phase transformation; Phase transitions; Polycrystals; Porcelain; Roughness; Silica; Silicon Dioxide; Strength testing; Stress, Mechanical; Surface Properties; Surface treatments; Tetragonal zirconia; Tetragonal zirconia polycrystals; X-ray diffraction; Yttria-stabilized zirconia; Yttrium; Yttrium oxide; Zirconia; Zirconium; Zirconium dioxide; Zirconium oxide partially stabilized by yttrium
• ISSN: 0928-4931; 1873-0191
• DOI: 10.1016/j.msec.2017.03.299

This study investigated the effects of different zirconia surface conditioning methods on the biaxial flexure strength, surface characteristics and fractographic analysis of a Y-TZP ceramic. Disc-shaped specimens were manufactured according to ISO 6872-2008 for biaxial flexure strength testing, and then randomly assigned into seven groups (n=30). Control (CTRL): without treatment; Tribochemical silica coating (TBS): specimens were sandblasted with silica-coated aluminum oxide particles (CoJet-Sand) for 10s; Silica nanofilm (SNF): specimens were silica coated with a 5nm SiO2 nanofilm; and four protocols of low-fusing porcelain glaze (GLZ): etching with 10% hydrofluoric acid gel (HF) for 1min (GLZ1), 5min (GLZ5), 10min (GLZ10) and 15min (GLZ15). Phase transformation, roughness, micro-morphological, flexural analysis tests, and fractographic analyses were performed. X-ray diffraction (XRD) analysis showed that the TBS promoted the highest m-phase content (20.35). However, for the GLZ groups, XRD analysis was not sensitive enough to obtain an accurate reading for phase transformation. The GLZ group had the highest roughness values. The TBS group had the highest characteristic strength (1291.38MPa), followed by SNF (999.26MPa). These results suggest that (TBS) and (SNF) treatments did not reduce the mechanical properties, while (GLZ) led to a degradation in the mechanical properties. •The tribochemical treatment did not impair mechanical performance of Y-TZP ceramic.•Silica nanofilm deposition also did not impair mechanical performance of Y-TZP.•The glaze application seems to promote deterioration of mechanical performance.