Contact damage in artificially aged 3Y-TZP
Visualitza/Obre
Estadístiques de LA Referencia / Recolecta
Inclou dades d'ús des de 2022
Cita com:
hdl:2117/20912
Tipus de documentArticle
Data publicació2010
Condicions d'accésAccés obert
Llevat que s'hi indiqui el contrari, els
continguts d'aquesta obra estan subjectes a la llicència de Creative Commons
:
Reconeixement-NoComercial-SenseObraDerivada 3.0 Espanya
Abstract
Tetragonal zirconia polycrystals doped with 3% mol of yttria (3Y
-
TZP) are increasingly
employed
as implants in the
human
body, because they
are biocompatible and
have relatively high strength and fracture toughness. These
properties are related to the small submicrometer grain size and to the operation of a toughening mechanism
around
cracks which is referred
to
as phase tra
nsformation toughening. Another important feature of 3Y
-
TZP is the
phenomenon of low temperature degradation (LTD) that takes place in contact with water at temperatures in an interval
around 250 ºC. Water activates t
-
m transformation at the surface and pr
ogresses inside the body producing a t
-
m surface
transformed layer. As a result, roughness and microcracking are produced in the surface. In a first stage, for short times
of
ageing
, this layer is responsible for degradation of surface mechanical propertie
s; at a later stage, after long
degradation times, it induces a strong reduction in the bulk strength.
In this paper we present a study of the mechanical behaviour of hydrothermal degraded
3Y
-
TZP
under monotonic
and
cyclic
spherical indentation. The inves
tigation is focused mainly on analyzing the mechanical response of the material
under spherical indentation in terms of the degraded layer. Plastic deformation and cracking induced by spherical
contact loading are studied under increasing loads in hydrothe
rmally degraded and in as sintered specimens.
The
contact hardness and elastic modulus of the degraded layer are extracted from nanoindentation using continuous
stiffness measurements.
It is found that permanent damage induced in degraded specimens is alwa
ys larger than in as
sintered specimens. Critical loads to induce ring cracking in degraded specimens are lower than in as sintered specimens
CitacióDe Armas, Z. [et al.]. Contact damage in artificially aged 3Y-TZP. "Anales de mecánica de la fractura", 2010, vol. 27, núm. 2, p. 517-522.
ISSN0213-3725
Versió de l'editorhttp://www.gef.es/Congresos/27/pdf/100.pdf
Fitxers | Descripció | Mida | Format | Visualitza |
---|---|---|---|---|
100.pdf | 741,2Kb | Visualitza/Obre |