INVESTIGADORES
AVALOS Martina Cecilia
artículos
Título:
Mechanical and microstructural behaviour of isothermally
Autor/es:
A.F.ARMAS; C. PETERSEN; R. SCHMITT; M AVALOS; I. ALVAREZ-ARMAS
Revista:
JOURNAL OF NUCLEAR MATERIALS
Editorial:
The Netherland
Referencias:
Lugar: Elsevier; Año: 2002 vol. 307 p. 509 - 513
ISSN:
0022-3115
Resumen:
Isothermal low cycle fatigue (LCF) and thermal low cycle fatigue results in the temperature range between room
temperature and 823 K of the quenched and tempered reduced activation ferritic/martensitic steels F82H mod. and
EUROFER 97 are reported. Under these test conditions both steels show, after the first few cycles and for both types of
tests, a pronounced cyclic softening up to failure. The softening during LCF tests described by a simple empirical
relationship is dependent on temperature but independent of the total strain amplitude of the tests. From the analysis of
the hysteresis loops and corroborated by electron microscopy observations it can be concluded that the cyclic softening
is produced by the softening observed in the internal stress as a consequence of the evolution of the microstructure.
During cycling, the martensitic lath structure with high dislocation density and carbides along the lath interfaces evolves
to a softer dislocation subgrain structure. This conclusion could be correlated with transmission electron microscopy
observations.