INTEMA   05428
INSTITUTO DE INVESTIGACIONES EN CIENCIA Y TECNOLOGIA DE MATERIALES
Unidad Ejecutora - UE
artículos
Título:
Characterization and Mechanical Behavior of Ceramic Rings
Autor/es:
A.G. TOMBA MARTÍNEZ; M.M. REBOREDO; A. L. CAVALIERI
Revista:
JOURNAL OF MATERIALS SCIENCE
Editorial:
Springer
Referencias:
Año: 2007 vol. 42 p. 5036 - 5045
ISSN:
0022-2461
Resumen:
Diametral compression is usually used to determine the mechanical resistance of cylindrical
ceramic specimens. This work deals with the possibility employing diametral compression in order to eval-
uate the mechanical response of ceramic rings, by testing two sets of rings (used as pump seals) that had
two different sizes. The rings were characterized by different techniques: qualitative X-ray diffraction,
apparent density and porosity measurements, determination of Vickers hardness, surface roughness, and
microstructural analysis. a-alumina was identified as the majority crystalline phase in both types of rings.
The porosities were rather similar, even though the observed mean grain size of the large rings was slightly
larger. Significant differences were observed in the average roughness. Diametral compression tests at
room temperature were carried out on a statistical number of each ring set. The fracture features were
analyzed by ocular inspection and SEM observation of the fracture surfaces. Several approaches were used
to estimate the fracture strengths: three analytical formulae with and without an empirical constant, and a
finite element calculation. The simplest approach, an analytical formula that only requires the knowledge of
the geometrical magnitudes of rings besides de fracture loads, gave a conservative estimation of the
mechanical strength of rings and a limited explanation of fracture features. On the other hand, the numerical
model being the most complex and informative of the approaches, gave the complete stress distributions.a-alumina was identified as the majority crystalline phase in both types of rings.
The porosities were rather similar, even though the observed mean grain size of the large rings was slightly
larger. Significant differences were observed in the average roughness. Diametral compression tests at
room temperature were carried out on a statistical number of each ring set. The fracture features were
analyzed by ocular inspection and SEM observation of the fracture surfaces. Several approaches were used
to estimate the fracture strengths: three analytical formulae with and without an empirical constant, and a
finite element calculation. The simplest approach, an analytical formula that only requires the knowledge of
the geometrical magnitudes of rings besides de fracture loads, gave a conservative estimation of the
mechanical strength of rings and a limited explanation of fracture features. On the other hand, the numerical
model being the most complex and informative of the approaches, gave the complete stress distributions.