Stability of Y-TZP during hydrothermal treatment: neutron experiments and stability considerations

被引:75
作者
Schubert, H
Frey, F
机构
[1] Tech Univ Berlin, Inst Werkstoffwissensch & Technol, D-10587 Berlin, Germany
[2] Sekt Kristallog Ludwig Maximillians Univ, Dept Geo & Umweltwissensch, Munich, Germany
关键词
corrosion; degradation; martensitic transformation; elastic recoil detection analysis; neutron diffraction; TZP;
D O I
10.1016/j.jeurceramsoc.2004.03.025
中图分类号
TQ174 [陶瓷工业]; TB3 [工程材料学];
学科分类号
0805 ; 080502 ;
摘要
The degradation of yttria-stabilised zirconia in humid atmospheres at temperatures around 250 degrees C is influenced by a number of microstructural parameters. The corrosive attack starts from the surface and is associated with the tetragonal to monoclinic transformation. In order to investigate structural changes chemically homogeneous single phase t-powders had been hydrothermally treated in a D2O-atmosphere and subsequently investigated by neutron diffraction. Slight structural changes were observed after water treatment: a general contraction of both a and c parameters, hence, the "free" structural z(oxygen) parameter as well as the c/a-ratio are closer to the values of cubic zirconia. In this paper the structural changes due to the penetration of water radicals during hydrolysis are discussed. They give rise to stresses which then have an impact on the energy balance between the tetragonal and the monoclinic phase (martensitic transformations). Since the powder state can be assumed to be mostly free from macro straining, the changes of the lattice constants were used to deduct a shape change tensor. Hence assuming linear elastic behaviour (isotropic elastic.modulus of 260 GPa for both a surface grain and its environment) maximum stresses of 328 MPa for the a-axis and 488 MPa for the C-axis were found. Thus, water radicals basically lead to further tensile stresses in the surface which increase the energy - difference between the t and mt phase, i.e. a further destabilisation. (c) 2004 Elsevier Ltd. All rights reserved.
引用
收藏
页码:1597 / 1602
页数:6
相关论文
共 21 条
[1]   Solid state 15N NMR and theoretical studies of primary and secondary geometric H/D isotope effects on low-barrier NHN-hydrogen bonds [J].
Benedict, H ;
Limbach, HH ;
Wehlan, M ;
Fehlhammer, WP ;
Golubev, NS ;
Janoschek, R .
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 1998, 120 (12) :2939-2950
[2]  
CERAMTEC AG, DATA SHEET ZN 100 MA
[3]  
CHEN IW, ADV CERAMICS, V2, P33
[4]  
CHRISTIAN JW, 1975, THEORY TRANSFORMATIO, V1
[5]  
FREY F, 1994, STRUKTUREN EIGENSCHA, V5, P383
[6]   PHASE-CHANGE AND MECHANICAL-PROPERTIES OF ZRO2-Y2O3 SOLID ELECTROLYTE AFTER AGING [J].
KOBAYASHI, K ;
KUWAJIMA, H ;
MASAKI, T .
SOLID STATE IONICS, 1981, 3-4 (AUG) :489-493
[7]  
KRUSE O, SCI TECHNOILOGY ZIRC, V5, P163
[8]  
KRUSE O, 1994, STABILITATSUNTERSUCU, P393
[9]   DEGRADATION DURING AGING OF TRANSFORMATION-TOUGHENED ZRO2-Y2O3 MATERIALS AT 250-DEGREES-C [J].
LANGE, FF ;
DUNLOP, GL ;
DAVIS, BI .
JOURNAL OF THE AMERICAN CERAMIC SOCIETY, 1986, 69 (03) :237-240