Numéro
J. Phys. Colloques
Volume 43, Numéro C4, Décembre 1982
ICOMAT-82
International Conference on Martensitic Transformations
Page(s) C4-803 - C4-808
DOI https://doi.org/10.1051/jphyscol:19824131
ICOMAT-82
International Conference on Martensitic Transformations

J. Phys. Colloques 43 (1982) C4-803-C4-808

DOI: 10.1051/jphyscol:19824131

FATIGUE OF THERMOELASTIC Cu-Zn-Al ALLOYS

R. Oshima et N. Yoshida

Department of Material Physics, Faculty of Engineering Science, Osaka University, Toyonaka, Osaka 560, Japan


Abstract
Fatigue testing of polycrystalline thermoelastic β1 Cu-Zn-Al alloys has been performed by dynamical loading at various temperatures between 40°C and -196°C in a push-pull deformation mode. Fatigue curves or S-N diagrams were obtained. The fatigue substructures were examined at room temperature by optical and electron microscope observations. It is found that the martensite phase exhibits longer fatigue life than the austenite phase, and the fatigue limit of the martensite phase is observed at the maximum strain of 0.5% in the temperature range below -70°C. No fatigue limit is obtained in the austenite phase. Most fatigue failure take place along the grain boundaries of the austenite irrespective of the testing temperature, and some occur along the martensite variant interfaces. It is suggested that the strengthening of the grain boundaries of the material is the most important requirement in order to obtain long fatigue life.