scholarly journals Molybdenum Oxide and Nickel Nitrate as Cooperative Sintering Aids for Yttria-Stabilized Zirconia

Materials ◽  
2020 ◽  
Vol 13 (12) ◽  
pp. 2875
Author(s):  
Clay Hunt ◽  
John Kyle Allemeier ◽  
David Driscoll ◽  
Adam Weisenstein ◽  
Stephen Sofie
Keyword(s):  
Crystal Structure ◽  
Sintering Temperature ◽  
Yttria Stabilized Zirconia ◽  
Spontaneous Generation ◽  
Sintering Aids ◽  
Stabilized Zirconia ◽  
Sintering Aid ◽  
Molybdenum Compound ◽  
Order Of Magnitude ◽  
Nano Rods

The entirely accidental observation of increased sintering performance of nickel-infiltrated yttria-stabilized zirconia (8YSZ) in a molybdenum and oxygen rich atmosphere was explored. Molybdenum and nickel were found to be synergistic sintering aids for 8YSZ. However, sintering had to take place in an atmosphere of flowing oxygen. Samples sintered in air consistently burst. The sintering performance, microstructure, and crystal structure of 8YSZ with additions of both Mo and Ni together are compared to the sintering performance, microstructure, and crystal structure of pure 8YSZ, 8YSZ with only Ni added as a sintering aid, and 8YSZ with only Mo added as a sintering aid. Enhanced densification and grain growth is observed in the Mo–Ni 8YSZ samples when compared to all other sintering samples. Order of magnitude sintering rate increases are observed in the Mo–Ni 8YSZ over that of pure 8YSZ. With a maximum sintering temperature of 1200 °C and a one-hour dwell, sintered densities of 85% theoretical density (5.02 g⁄cm3) are achieved with the Mo–Ni samples: a 57% increase in density over pure 8YSZ sintered with the same sintering profile. EIS results suggest conductivity may not be negatively impacted by the use of these two sintering aids at temperatures above 750 °C. Finally, the spontaneous generation of nickel-molybdenum nano-rods was observed on the 5, and 10 mol.% Mo–Ni infiltrated 8YSZ samples after being left under vacuum in a scanning electron microscope chamber, suggesting evaporation of a possible nickel–molybdenum compound from the sample fracture surfaces.

Microstructural examination of modified yttria stabilized zirconia by EM analytical techniques

1986 ◽  
Vol 44 ◽  
pp. 842-843
Author(s):  
W. W. Davison ◽  
R. C. Buchanan
Keyword(s):  
Mechanical Properties ◽  
Analytical Techniques ◽  
Yttria Stabilized Zirconia ◽  
Stabilized Zirconia ◽  
Transmission Microscopy ◽  
Sintering Aid ◽  
Densification Temperature ◽  
Chemical Inertness ◽  
Scanning Transmission ◽  
Microstructural Examination

Yttria stabilized zirconia (YSZ) has become a significant technological material due to its high ionic conductivity, chemical inertness, and good mechanical properties. Temperatures on the order of 1700°C are required, however, to densify YSZ to the degree necessary for good electrical and mechanical properties. A technique for lowering the densification temperature is the addition of small amounts of material which facilitate the formation of a liquid phase at comparatively low temperatures. In this study, sintered microstructures obtained from the use of Al2O3 as a sintering aid were examined with scanning, transmission, and scanning transmission microscopy (SEM, TEM, and STEM).

Structure and Microwave Dielectric Properties of (Ca0.9375Sr0.0625)0.25 (Li0.5Sm0.5)0.75TiO3 Ceramics with B2O3-CuO Sintering Aids

2011 ◽  
Vol 284-286 ◽  
pp. 1442-1446
Author(s):  
Yue Ming Li ◽  
Zong Yang Shen ◽  
Zhu Mei Wang ◽  
Hua Zhang ◽  
Yan Hong ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Dielectric Properties ◽  
Sintering Temperature ◽  
Microwave Dielectric Properties ◽  
Microwave Dielectric Ceramics ◽  
Sintering Aids ◽  
Oxide Mixture ◽  
High Permittivity ◽  
Microwave Dielectric ◽  
Dielectric Ceramics

The B2O3-CuO oxide mixture (abbreviated as BC) was selected to lower the sintering temperature of (Ca0.9375Sr0.0625)0.25(Li0.5Sm0.5)0.75TiO3 (abbreviated as CSLST) microwave dielectric ceramics by solid sate reaction technique. The effects of BC doping amounts on the crystal structure, microstructure and microwave dielectric properties of the ceramics were investigated. For the ceramic sample with the composition of CSLST + 5 wt% BC, its sintering temperature was reduced to 1000 °C as compared to 1200 °C for pure CSLST. In addition to the obtained good microwave dielectric properties as follows: εr = 80.4, Q×f = 1380 GHz, τf = -32.89 ×10-6/°C, this ceramic was a desirable high-permittivity microwave dielectric candidate for low-temperature cofired ceramic (LTCC) applications.

Synthesis and Properties of Composite Stabilized ZrO2

2013 ◽  
Vol 544 ◽  
pp. 68-71
Author(s):  
Jing Hui Cui ◽  
Tao Feng ◽  
Jin Feng Xia ◽  
Dan Yu Jiang ◽  
Ge Ming Liu ◽  
...  
Keyword(s):  
High Temperature ◽  
Sintering Temperature ◽  
Decomposition Temperature ◽  
Yttria Stabilized Zirconia ◽  
Stabilized Zirconia ◽  
Muffle Furnace ◽  
Flexure Strength ◽  
Different Temperatures ◽  
Zirconia Electrolyte

Through Mechanical grounding method, CaZrO3 – 8YSZ(8% in mol yttria stabilized zirconia) electrolyte samples with different amounts of CaZrO3 at 10wt%, 20wt%, 30wt% were sintered at different temperatures in Muffle furnace. The decomposition temperature of CaZrO3 is 825°C-900°C under one atmosphere. At high temperature, CaZrO3 decomposes into CaO and ZrO2. So Y2O3-CaO-ZrO2 complex is composed. The effects of the sintering temperature and the contents of the CaZrO3 on the conductivity, porosity, flexure strength, hardness were investigated. XRD and SEM were used to analyse the compositions and microcosmic morphology.

Low-Temperature Sintering and Microwave Dielectric Properties of CaWO4-Mg2SiO4 Ceramics

2014 ◽  
Vol 933 ◽  
pp. 12-16 ◽  
Author(s):  
Chung Long Pan ◽  
Ping Cheng Chen ◽  
Tsu Chung Tan ◽  
Wei Cheng Lin ◽  
Chun Hsu Shen ◽  
...  
Keyword(s):  
Dielectric Properties ◽  
Solid State ◽  
Liquid Phase ◽  
Sintering Temperature ◽  
Microwave Dielectric Properties ◽  
Liquid Phase Sintering ◽  
Low Temperature Sintering ◽  
Sintering Aids ◽  
Sintering Aid ◽  
Microwave Dielectric

The effect of V2O5addition on the microstructures and the microwave dielectric properties of 0.9CaWO4-0.1Mg2SiO4(9CWMS) ceramics prepared by conventional solid-state routes have been investigated. The V2O5were selected as liquid phase sintering aids to lower the sintering temperature of 9CWMS ceramics. A small amount of V2O5(0.25~1 wt%) were used for sintering aid and led to high densification at 1050°C. The dielectric properties of 9CWMS ceramics with V2O5additions are strongly dependent on the densification, the microstructure. As the amount of V2O5additives increased from 0.25 to 1.0 wt%, the dielectric constantsεrdecreased following the trend with density. The quality valuesQdecreased with the increase of V2O5amount for all sintering temperatures. The 0.25 wt% V2O5-doped 0.9CaWO4-0.1Mg2SiO4ceramicssintered at 1080°C for 2 h had the optimum dielectric properties: εr= 5.7;Q×f= 73000 (at 14 GHz).

Performance Investigation of Dual Layer Yttria-Stabilized Zirconia–Samaria-Doped Ceria Electrolyte for Intermediate Temperature Solid Oxide Fuel Cells

2016 ◽  
Vol 13 (1) ◽  
Author(s):  
Ryan J. Milcarek ◽  
Kang Wang ◽  
Michael J. Garrett ◽  
Jeongmin Ahn
Keyword(s):  
Fuel Cell ◽  
Buffer Layer ◽  
Sintering Temperature ◽  
Solid Oxide ◽  
Yttria Stabilized Zirconia ◽  
Cell Performance ◽  
Doped Ceria ◽  
Oxide Fuel ◽  
Stabilized Zirconia ◽  
Fuel Cell Performance

The performance of yttria-stabilized zirconia (YSZ)–samaria-doped ceria (SDC) dual layer electrolyte anode-supported solid oxide fuel cell (AS-SOFC) was investigated. Tape-casting, lamination, and co-sintering of the NiO–YSZ anode followed by wet powder spraying of the SDC buffer layer and BSCF cathode was proposed for fabrication of these cells as an effective means of reducing the number of sintering stages required. The AS-SOFC showed a significant fuel cell performance of ∼1.9 W cm−2 at 800 °C. The fuel cell performance varies significantly with the sintering temperature of the SDC buffer layer. An optimal buffer layer sintering temperature of 1350 °C occurs due to a balance between the YSZ–SDC contact and densification at low sintering temperature and reactions between YSZ and SDC at high sintering temperatures. At high sintering temperatures, the reactions between YSZ and SDC have a detrimental effect on the fuel cell performance resulting in no power at a sintering temperature of 1500 °C.

INFLUENCE OF SINTERING TEMPERATURE ON TRANSLUCENCY OF YTTRIA-STABILIZED ZIRCONIA FOR DENTAL CROWN APPLICATIONS

2016 ◽  
Vol 78 (11-3) ◽  
Author(s):  
Chin Chuin Hao ◽  
Andanastuti Muchtar ◽  
Che Husna Azhari ◽  
Masfueh Razali ◽  
Mohamed Aboras
Keyword(s):  
Light Scattering ◽  
Light Transmission ◽  
Sintering Temperature ◽  
High Density ◽  
Yttria Stabilized Zirconia ◽  
Integrating Sphere ◽  
Stabilized Zirconia ◽  
Scattering Effect ◽  
Light Scattering Effect ◽  
Dental Crown

This study aims to investigate the effect of sintering temperature on the translucency of yttria-stabilized zirconia (YSZ) for dental crown applications. YSZ suspension was treated by colloidal processing and 24 h of sedimentation to eliminate agglomerates and aggregates. The green bodies of YSZ were then shaped into pellets through slip casting. These bodies were sintered into a final shape at 1450 °C–1650 °C. The densities of the specimens were measured using Archimedes method. Light transmission of the YSZ specimen was also evaluated using a spectrophotometer with an integrating sphere. Morphological analysis was conducted with field-emission scanning electron microscopy. Results showed that sintering temperature significantly influenced the density, light transmission, and microstructure of YSZ. High sintering temperatures produced YSZ with a compact and homogeneous microstructure and a high density. Furthermore, the low light scattering effect on the porosity-free microstructure yielded light transmission as high as 37% in YSZ sintered at 1650 °C. The optimal sintering temperature was found to be 1600 °C, at which 34% light transmission was generated. In conclusion, high sintering temperatures improved the translucency of YSZ. This effect was attributed to effective densification of grains and elimination of pores at high temperatures, thereby alleviating the light scattering effect of the pores. At the optimal temperature, YSZ with high density and translucency and a compact microstructure was formed

Processing of porous yttria-stabilized zirconia tapes: Influence of starch content and sintering temperature

2009 ◽  
Vol 35 (5) ◽  
pp. 1783-1791 ◽  
Author(s):  
María P. Albano ◽  
Liliana B. Garrido ◽  
Kevin Plucknett ◽  
Luis A. Genova
Keyword(s):  
Sintering Temperature ◽  
Starch Content ◽  
Yttria Stabilized Zirconia ◽  
Stabilized Zirconia
Sign in / Sign up

Export Citation Format

Share Document