The effect of ceria co-doping on chemical stability and fracture toughness of Y-TZP (1995)
Boutz, M.M.R., Winnubst, A.J.A., Langerak Van, B., Kreuwel, K., Burggraaf, A.J.
The fracture toughness and ageing resistance of yttria, ceria-stabilized tetragonal zirconia polycrystals (Y, Ce-TZP) were evaluated as a function of grain size and ceria content. Very fine grained,...
Effect of additives on densification and deformation of tetragonal zirconia (1994)
Boutz, M.M.R., Winnubst, A.J.A., Hartgers, F., Burggraaf, A.J.
The effect of additives (Bi2O3, Fe2O3) on densification and creep rates of tetragonal ZrO2-Y2O3 has been investigated. In Bi2O3-doped Y-TZP, a reactive liquid forms at temperatures above...
Improvement of mechanical properties of zirconia-toughened alumina by sinter forging (1994)
He, Y.J., Winnubst, A.J.A., Verweij, H., Burggraaf, A.J.
ZTA powder with a composition of 85 wt% alumina/15 wt% zirconia was prepared by a gel precipitation method. Sinter forging was performed with this powder to enhance the mechanical properties of ZTA...
Sinter forging of zirconia toughened alumina (1994)
He, Y.J., Winnubst, A.J.A., Verweij, H., Burggraaf, A.J.
Sinter forging experiments have been carried out on powder compacts of zirconia toughened alumina (ZTA) Ceramics Alumina-15 wt% zirconia was prepared by a gel precipitation method and calcined at...
Oxygen semipermeability of erbia-stabilized bismuth oxide (1992)
Bouwmeester, H.J.M., Kruidhof, H., Burggraaf, A.J., Gellings, P.J.
The isothermal permeability of oxygen through sintered dense disks of bismuth oxide stabilized with 25 mol% erbia (BE25) has been studied at 610–810°C and oxygen pressures of 0.0001–1 atm. It is...
Mechanical properties of ultra-fine grained zirconia ceramics (1992)
Bouma, J.S., Winnubst, A.J.A., Burggraaf, A.J.
The mechanical properties of tetragonal zirconia (TZP) materials doped with Y, Ce or Ti were studied as a function of temperature and grain size. Fine grained Y-TZP (grain size < 0.3 mgrm) shows...
Surface and grain boundary analysis of doped zirconia ceramics studied by AES and XPS (1992)
Winnubst, A.J.A., Burggraaf, A.J.
The surface- and grain boundary composition of Y, Ce and Ti doped zirconia were studied by X-ray Photoelectron Spectroscopy and Auger Electron Spectroscopy/Scanning Auger Microscopy. The grain...
Kuipers, R.A., Vries De, K.J., Burggraaf, A.J.
The influence of the microstructure on the electrical properties and polarization behavior of thin porous ceramic electrodelayers used in solid oxide fuel cells has been investigated. Thin layers...
Kruidhof, H., Vries De, K.J., Burggraaf, A.J.
The thermochemical stability of fast oxygen ion conducting yttria stabilized bismuthoxide (YSB) solid solutions containing 22.0–32.5 mol% of yttria was investigated. It was shown that in the...
Powder preparation and compaction behaviour of fine-grained Y-TZP (1990)
Winnubst, A.J.A., Burggraaf, A.J.
Two wet chemical preparation methods are described for yttria-doped tetragonal zirconia powders. Both methods yield powders with an extremely small crystallite size (8 nm) and a narrow size...
Lin, Y.S., Vries De, K.J., Burggraaf, A.J.
The electrochemical vapor deposition (EVD) method is a very promising technique for making gas-tight dense solidelectrolyte films on porous substrates. In this paper, theoretical and experimental...
Microstructure characteristics of ultra-fine ZrO2---Y2O3 ceramic powdersstar, open (1989)
Winnubst, A.J.A., Burggraaf, A.J.
Yttria-doped zirconia powders with an extremely small crystallite size (8 nm) and a narrow size distribution have been prepared by gel precipitation methods. Precipitation of an alkoxide solution in...
Kruidhof, H., Seshan, K., Vries De, K.J., Burggraaf, A.J.
Coprecipitation as a method of preparation for bismuth oxides based ceramics yields relatively strong and machineable materials in comparison with the solid state reaction. Compositions within the...
Kruidhof, H., Seshan, K., Lippens Jr., B.C., Gellings, P.J., Burggraaf, A.J.
A study of the preparative variables in the synthesis of ceramics based on Bi2O3-Er2O3 solid solutions has shown that the best results are obtained with a coprecipitation method. Critical parameters...
Response behaviour of oxygen sensing solid electrolytes (1985)
Winnubst, A.J.A., Scharenborg, A.H.A., Burggraaf, A.J.
The response time (t r) after a step change in oxygen partial pressure was investigated for some solid electrolytes used in Nernst type oxygen sensors. The electrolyte as well as the (porous)...
Preparation and electrical properties of a monophasic ZrO2---Y2O3---Bi2O3 solid electrolyte (1984)
Winnubst, A.J.A., Burggraaf, A.J.
A preparation method is described of monophasic yttria stabilized zirconia doped with Bi2O3. This material is prepared from a homogeneous power which, after pressing, is sintered in a Bi2O3...
The luminescence of yitria stabilized zirconia doped with Bi2O3 (1984)
Blasse, G., Zhiran, Hao, Winnubst, A.J.A., Burggraaf, A.J.
Yttria stabilized zirconia doped with Bi2O3 shows an efficient luminescence due to the Bi3+ ions. Two luminescent centres were observed which are ascribed to BiO8 and BiO7 groups.
The electrode resistance of ZrO2---Y2O3(-Bi2O3) solid electrolytes with Pt electrodes (1984)
Winnubst, A.J.A., Scharenborg, A.H.A., Burggraaf, A.J.
The electrode resistance (Re1) at low over-voltages has been determined for Bi2O3 free and Bi2O3 doped yttria-stabilized zirconia with sputtered platinum electrodes. The anode and cathode resistances...
Mechanical properties and fracture behaviour of ZrO2-Y2O3 ceramics (1983)
Winnubst, A.J.A., Keizer, K., Burggraaf, A.J.
Stabilized ZrO2-Y2O3 ceramics have been prepared with varying grain sizes and microstructures with the help of different preparation techniques. Bi2O3 has been added as a sinter aid to some of the...
AES/STEM grain boundary analysis of stabilized zirconia ceramics (1983)
Winnubst, A.J.A., Kroot, P.J.M., Burggraaf, A.J.
Semiquantitative Auger Electron Spectroscopy (AES) on pure monophasic (ZrO2)0.83(YO1.5)0.17 was used to determine the chemical composition of the grain boundaries. Grain boundary enrichment with Y...
Verkerk, M.J., Hammink, W.J., Burggraaf, A.J.
The electrode behavior of Pt-sputtered and PT-gauze electrodes on ZrO2-Y2O3, Bi2O3-Er2O3, and CeO2-Gd2O3 solid electrolyteswas investigated by means of d-c measurements in the temperature region of...
Verkerk, M.J., Burggraaf, A.J.
An equivalent electrical circuit that describes the electrode processes on different electrolytes, using porous Pt electrodes,is given. Diffusional processes are important and have to be presented by...
Effect of impurities on sintering and conductivity of yttria-stabilized zirconia (1982)
Verkerk, M.J., Winnubst, A.J.A., Burggraaf, A.J.
The effect of low concentrations of Fe2O3, Al2O3 and Bi2O3 on the sintering behaviour of (ZrO2)0.83 (YO1.5)0.17, made by alkoxide synthesis, has been investigated. The best results are achieved with...
High Oxygen Ion Conduction in Sintered Oxides of the Bi2O3-Dy2O3 System (1981)
Verkerk, M.J., Burggraaf, A.J.
The phase diagram of the Bi2O3-Dy2O3 system was investigated. A monophasicfcc structure was stabilized for samples containing 28.5–50.0 mole percent (m/o) Dy2O3. Above and below this concentration...
Ordering and diffuse phase transitions in Pb(Sc0.5Ta0.5)O3 ceramics (1979)
Stenger, C.G.F., Scholten, F.L., Burggraaf, A.J.
The ordering of the Sc3+ and Ta5+ ions in Pb (Sc0.5Ta0.5) O3 can be varied by proper heat treatments (1000–1500°C). The ferroelectric → paraelectric transition is strongly influenced by this...
Preparation and properties of new oxygen ion conductors for use at low temperatures (1979)
Keizer, K., Verkerk, M.J., Burggraaf, A.J.
Two new systems, Bi2O3---Er2O3 and ZrO2---Y2O3(CaO)---Bi2O3 were investigated. The first system has a homogeneous cubic, fluorite phase between 17.5 and 45.5 mol % Er2O3 and can be sintered to...
Anomalous dielectric behaviour of La(III) substituted lead titanate ceramics (1978)
Keizer, K., Lansink, G.J., Burggraaf, A.J.
In La(III) substituted PbTiO3 ceramics the behaviour of the reciprocal dielectric constant in the paraelectric phase can be described by the relation [...] with the exponent 1 γ
Wolters, M., Burggraaf, A.J., Thieme, C.L.H.
Lanthanum substituted lead zirconate-titanate (PLZT) ceramics of composition 11.1/55/45 have been studied by measuring high electric field properties. Dc bias, dielectric and P-E hysteresis loop...
Dielectric properties of (Pb,La)Zr0.55Ti0.45O3 ceramics have been investigated as functions of temperature and frequency. The dielectric constant as a function of temperature can be represented over...
The effect of grain size on unit-cell dimensions and dielectric properties has been studied in ceramic lanthana-substituted leadtitanate and leadtitanate-zirconate mixed crystals of the general...
Keizer, K., Janssen, E.H.J., Vries De, K.J., Burggraaf, A.J.
The synthesis of PbZr0.5Ti0.5O3 ceramics from the raw materials was reinvestigated in order to find relations in the characterizations for the products in various stages of the preparation procedure....