Sintering Properties of Tetragonal Zirconia Nanopowder Preparation of the NaCl + KCl Binary System by the Sol–Gel–Flux Method

Abstract

Tetragonal zirconia nanopowders (3Y-TZP NPs) stabilized by 3 mol % Y2O3 were synthesized by a novel sol–gel–flux method. The effects of calcination temperature, Y2O3 content, and molten salt system (NaCl + KCl binary system and NaCl unary system) on the phase composition and morphology of nanopowders (NPs) were investigated. Meanwhile, the sintering properties of the prepared 3Y-TZP NPs were studied. The 3Y-TZP NPs and sintered ceramics were characterized by thermogravimetry-differential scanning calorimetry (TG-DSC), X-ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM), Brunauer–Emmett–Teller (BET) analysis, and X-ray fluorescence (XRF) spectroscopy. The results show that the optimum calcination temperature for obtaining dispersed ZrO2 NPs is reduced from 800 to 660 °C when the NaCl unary system is substituted by the NaCl + KCl binary system. 3Y-TZP NPs with a single tetragonal phase are obtained in the NaCl + KCl binary system when Y2O3 content in the raw material is 5 mol %. The average particle size of the obtained ZrO2 NPs is reduced from 47.25 nm in the unary system to 26.18 nm in the binary system because of the lower calcining temperature. Furthermore, the 3Y-TZP NPs obtained in the binary system have narrower particle size distribution and better sintering performance than ZrO2 NPs obtained in the unary system. After sintering for 4 h at 1200 °C, the former generated 3Y-TZP ceramics with higher density and finer grain size. This work produced narrow-distributed well-dispersed 3Y-TZP NPs with quasi-spherical morphology, which are good candidates for the applications, including oxygen sensors and thermal barrier coatings.

Effects of Surface Treatments and Cement Type on Shear Bond Strength between Titanium Alloy and All-Ceramic Materials

“…This may be due to microcracks in the material during screw hole milling and supports the production of restorations from blocks with self-occlusal screw holes. For these reasons, this study evaluated the performance of two-piece titanium hybrid abutments and ceramic and ceramic-like materials [ 20 , 21 , 22 ].…”

Effect of Antirotational Two-Piece Titanium Base on the Vertical Misfit, Fatigue Behavior, Stress Concentration, and Fracture Load of Implant-Supported Zirconia Crowns

“…Using computer-aided design software (Rhinoceros version 5.0 SR8, McNeel North America, Seattle, WA, USA), a fixation cylinder model was recreated for an in vitro study, maintaining dimensions of 25 × 20 mm. Implant designs (4.3 × 11.5 mm) were then drawn based on 4.3 mm diameter circles to determine the implant’s three-dimensional structure [ 18 ]. The models were created following the BioCAD protocol using STL files provided by Nueva Galimplant (Sarria, Lugo, Spain).…”

“…It finds extensive use in oral repair, tissue engineering, electrolyte materials, and structural applications. However, zirconia face issues like blockage, detachment, and cracking in high-stress environments [ 17 , 18 ]. To overcome this limitation, a hybrid component has been developed, featuring a titanium base (connection link) bonded to a mesostructure [ 19 , 20 ].…”

“…Hybrid abutments are available for external hexagon, internal hexagon, Morse taper, and alternative prosthetic connections [ 18 ]. It can be used at different heights and angulations, indicated for anterior and posterior crowns [ 19 , 20 , 21 , 22 , 23 ].…”

The Effect of Restoration Thickness on the Fracture Resistance of 5 mol% Yttria-Containing Zirconia Crowns

“…Crystal structure modifications induced by an increased yttrium oxide content from 3 to 5 mol% led to the development of translucent 5 mol% yttria-stabilized zirconia polycrystal (5Y-Z). This zirconia contains a cubic crystal content of approximately 50% of the structure, which allows improved light transmission [5][6][7]. In contrast, the higher proportion of cubic crystals in 5Y-Z also contributes to its weaker flexural strength and fracture toughness due to the lack of transformation toughening that occurs in 3Y-Z [8,9].…”