title: Application of Micro-Raman Spectroscopy to the Study of Yttria-Stabilized Tetragonal Zirconia Polycrystal (Y-TZP) Phase Transformation.
abstract: The aim of this study was to perform micro-Raman spectroscopy as an alternative and nondestructive method to identify the phase transformation of zirconia after mechanical stress. The groups evaluated were experimental zirconia, zirconcad, IPS e.max ZirCad, and In Ceram YZ. Ten specimens were constructed for each group (n = 30) and subjected to a three-point bending test with a crosshead speed of 0.5 mm/min. The fractured surfaces were analyzed by micro-Raman spectroscopy. The laser power was kept at 10 mW, and scanning was performed in three regions of the fractured surface: (i) near the source of the failure (region of tensile stress), (ii) central to the fractured surface, and (iii) far from the source of failure. All materials showed the characteristic bands of tetragonal and monoclinic phases of zirconia. All zirconia studied showed a monoclinic phase in the tensile stress region. Micro-Raman spectroscopy was effective in detecting the presence of crystalline phases in polycrystals ceramics.
authors.affiliation: Department of Dentistry, Endodontics and Dental Materials, Bauru School of Dentistry, University of São Paulo, Alameda Octávio Pinheiro Brisola, 9-75, Vila Universitária, Bauru SP, 17012-901, Brazil.
authors.forename: Carla Müller
authors.initials: CM
authors.lastname: Ramos
authors.forename: Américo Sheitiro
authors.initials: AS
authors.lastname: Tabata
authors.forename: Paulo Francisco
authors.initials: PF
authors.lastname: Cesar
authors.forename: José Henrique
authors.initials: JH
authors.lastname: Rubo
authors.forename: Paulo Afonso Silveira
authors.initials: PA
authors.lastname: Fracisconi
authors.forename: Ana Flávia
authors.initials: AF
authors.lastname: Sanches Borges
mesh_terms: D003460:Crystallization; D044367:Phase Transition; D013059:Spectrum Analysis, Raman; D013314:Stress, Mechanical; D015019:Yttrium / Q000737:chemistry*; D015040:Zirconium / Q000737:chemistry*
chemical_list: D015019:Yttrium; D015040:Zirconium; C028541:zirconium oxide; C091417:yttria