Influence of Loading Rate on Fatigue Crack Propagation Property of Recycled PA 66 Material at High-Temperature above Tg

Autor: Hideto Suzuki, Tadao Haraguchi, Masashi Nakamura
Rok vydání: 2002
Předmět:
Zdroj: TRANSACTIONS OF THE JAPAN SOCIETY OF MECHANICAL ENGINEERS Series A. 68:1730-1736
ISSN: 1884-8338
0387-5008
DOI: 10.1299/kikaia.68.1730
Popis: In this study, high temperature fatigue crack propagation test of the engineering plastic material was carried out in order to clarify the effect of loading rate on the fatigue crack propagation property at the high temperature environment above Tg. Then, failure mechanism and loading rate dependence were evaluated. (1) The resistance against the crack propagation at 30 Hz that was high loading rate was more excellent than that at 10 Hz and 3 Hz which was low-loading rate. And, the resistance against the crack propagation at 10 Hz was equivalent to that at 3 Hz. (2) The resistance against the crack propagation of R 1 material remarkably decreased in comparison with that of virgin material. However, the resistance against the crack propagation of R 3 material was almost equal to that of R 1 material. (3) From the fractography using SEM the fracture surface at high loading rate was a brritle form, and the effect by the fatigue was big. In the meantime, that at low loading rate was a ductile form, and it seemed to overlap fatigue and creep. The viscoelastic effect of the matrix seems to remarkably appear in the fracture surface at low loading rate. (4) It was proven that the process zone dimension and the reinforced fiber length influenced the difference between fatigue crack proagation mechanism at the high loading rate and that at the low loading rate.
Databáze: OpenAIRE