Skip to main content

Mechanical Properties of Melt-Grown Alumina–Yttrium Aluminum Garnet Eutectics up to 1900 K

Buy Article:

$51.00 plus tax (Refund Policy)

Abstract:

Alumina/yttrium aluminum garnet (YAG) eutectic rods of 1 mm in diameter were grown by the laser-heated floating zone method at different rates to obtain microstructures with the same morphology but of very different domain size. The mechanical properties of the rods (hardness, toughness, strength) were measured at ambient temperature in the longitudinal and transverse directions and, in addition, the longitudinal flexure strength was determined up to 1900 K. The fracture resistance and the hardness of the eutectics at ambient temperature were isotropic and independent of the domain size. On the contrary, the longitudinal strength was significantly higher than the transverse one and increased linearly with the growth rate, reaching almost 2 GPa in the rods grown at 750 mm/h, which presented a submicrometer homogeneous microstructure. The critical defect size was equivalent to that of Al2O3 and YAG domains in the microstructure, and the strength was proportional to the inverse of the square root of the domain size. In addition, the strength retention of the eutectics was remarkable, and the rods with the finest microstructure withstood 1.53 GPa at 1900 K. The moderate reduction in strength at very high temperature was induced by the homogeneous coarsening of the microstructure.

Document Type: Research Article

DOI: http://dx.doi.org/10.1111/j.1551-2916.2005.00265.x

Affiliations: 1: Department of Materials Science, Polytechnic University of Madrid, E. T. S. de Ingenieros de Caminos, 28040 Madrid, Spain 2: Instituto de Ciencia de Materiales de Aragón, C.S.I.C.—Universidad de Zaragoza, 50009 Zaragoza, Spain

Publication date: June 1, 2005

Access Key

Free Content
Free content
New Content
New content
Open Access Content
Open access content
Subscribed Content
Subscribed content
Free Trial Content
Free trial content
Cookie Policy
X
Cookie Policy
Ingenta Connect website makes use of cookies so as to keep track of data that you have filled in. I am Happy with this Find out more