Sintering Temperature (sinter + temperature)

Distribution by Scientific Domains


Selected Abstracts


Tape Casting and Dielectric Properties of Zn2Te3O8 -Based Ceramics with an Ultra-Low Sintering Temperature

INTERNATIONAL JOURNAL OF APPLIED CERAMIC TECHNOLOGY, Issue 4 2009
Johanna Honkamo
The suitability of dielectric ceramics made of zinc tellurate (Zn2Te3O8) and titanium dioxide (TiO2) with an ultra-low sintering temperature (650°C) for tape casting and thus for the multimodule technique with Al electrodes was investigated. The properties of the tape before and after sintering as well as the amount of organic additives for the casting process and a thermal analysis of the tape up to 1000°C are reported. In addition, electrodes on a multilayer module made on stacked tapes were prepared using Al paste and postfiring, followed by relative permittivity and loss tangent measurements to verify the electrical performance of the whole structure. The dielectric properties of the stacked module without any electrodes were also measured. The results show that the composition is well suited for the tape process but extra care should be taken especially with the proper sintering temperature for optimized electrical performance. [source]


Enhancing Electrical Properties in NBT,KBT Lead-Free Piezoelectric Ceramics by Optimizing Sintering Temperature

JOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 8 2008
Ya-Ru Zhang
Conventional sintering of (Na1,xKx)0.5Bi0.5TiO3 (abbreviated as NKBTx, x=18,22 mol%) lead-free piezoelectric ceramics was investigated to clarify the optimal sintering temperature for densification and electrical properties. Both sintered density and electrical properties were sensitive to sintering temperature; particularly, the piezoelectric properties deteriorated when the ceramics were sintered above the optimum temperature. The NKBT20 and NKBT22 ceramics synthesized at 1110°,1170°C showed a phase transition from tetragonal to rhombohedral symmetry, which was similar to the morphotropic phase boundary (MPB). Because of such MPB-like behavior, the highest piezoelectric constant (d33) of about 192 pC/N with a high electromechanical coupling factor (kp) of about 32% were obtained in the NKBT22 ceramics sintered at 1150°C. [source]


Normal Sintering of (K,Na)NbO3 -Based Ceramics: Influence of Sintering Temperature on Densification, Microstructure, and Electrical Properties

JOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 12 2006
Yuhua Zhen
Normal sintering of Li-doped and Li/Ta-codoped potassium sodium niobate (KNbO3,NaNbO3, KNN)-based ceramics was investigated to clarify the optimal sintering condition for densification, microstructure, and electrical properties. It was found that density increased greatly within a narrow temperature range but tended to decrease when the sintering temperature slightly exceeded the optimal one, accompanied by the appearance of abnormal grain growth, which was considered to be due to the intensified volatilization of alkali metal oxides. Piezoelectric and dielectric properties also showed a similar relationship between the density and sintering temperature, but the highest piezoelectric strain coefficients were obtained at the temperatures lower than that for the highest density, because both densification and composition affect the electrical properties. The highest d33 value of 206 pC/N was obtained for the Li- and Ta-codoped KNN ceramics prepared at 1090°C. [source]


Influence of Copper(II) Oxide Additions to Zinc Niobate Microwave Ceramics on Sintering Temperature and Dielectric Properties

JOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 6 2001
Dong-Wan Kim
The effect of CuO additions on the firing temperature of ZnNb2O6 ceramics was investigated using dilatometry, transmission electron microscopy, and X-ray diffractometry. A 5 wt% CuO addition to ZnNb2O6 ceramics significantly lowered the firing temperature from 1150° to ,900°C. The presence of a CuO-rich intergranular phase in the specimen was observed and was evidence of the formation of a liquid phase during sintering. The composition of the liquid phase was (ZnCu2)Nb2O8. In particular, the low-fired ZnNb2O6 ceramics had good microwave dielectric characteristics,Q×f= 59 500, ,r= 22.1, ,f=,66 ppm/oC. These properties were correlated with the formation of a second phase, (ZnCu2)Nb2O8. [source]


Effect of Nickel Oxide/Yttria-Stabilized Zirconia Anode Precursor Sintering Temperature on the Properties of Solid Oxide Fuel Cells

JOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 3 2000
Søren Primdahl
An NiO/yttria-stabilized zirconia (YSZ) layer sintered at temperatures between 1100° and 1500°C onto dense YSZ electrolyte foils forms the precursor structure for a porous Ni/YSZ cermet anode for solid oxide fuel cells. Conflicting requirements for the electrochemical performance and mechanical strength of such cells are investigated. A minimum polarization resistance of 0.09 ,.cm2at 1000°C in moist hydrogen is obtained for sintering temperatures of 1300°,1400°C. The mechanical strength of the cells decreases with increased sintering temperature because of the formation of channel cracks in the electrode layers, originating in a thermal expansion coefficient mismatch between the layers. [source]