Microstructure and creep properties of alumina/zirconia ceramics

✍ Scribed by JoséMaria Calderón-Moreno; Antonio R. de Arellano-López; Arturo Domínguez-Rodríguez; Jules L. Routbort

• Publisher: Elsevier Science
• Year: 1995
• Tongue: English
• Weight: 869 KB
• Volume: 15
• Category: Article
• ISSN: 0955-2219
• DOI: 10.1016/0955-2219(95)00070-b

✦ Synopsis

High temperature creep of two zirconia toughened alumina ceramics, fabricated by powder processing and sol-gel precursors processing, has been studied in order to determine plastic deformation mechanisms. Compressive creep tests were carried out between 1300 and 145O"C, under stresses from IO to I50 MPa. For the sample fabricated from powders, a stress exponent of 1.4 and an activation energy of 580 kJ/mol were found below a critical stress of 40 MPa. For larger stresses, accelerated creep rates developed. In the specimens processed from precursors, values of 1.8 for the stress exponent and 540 kJ/mol for the activation energy, over the entire range of stresses have been determined.

Creep parameters and microstructural evolution of the samples during the experiments have been correlated with models to establish the dominant creep mechanism.