INVESTIGADORES
MALARRIA Jorge Alberto
congresos y reuniones científicas
Título:
Evolución de la microestructura y seguimiento del daño superficial en un acero duplex
Autor/es:
M.C. MARINELLI, I. ALVAREZ, J. MALARRÍA
Lugar:
San Nicolás (Argentina)
Reunión:
Conferencia; 2nd IAS Conference on Uses of Steel; 2004
Institución organizadora:
Instituto Argentino del Acero
Resumen:
The aim of the present work is to study the surface fatigue damage
evolution on specimens of superduplex stainless steals SAF 2507 and correlate
it with the dislocation structures.The dislocation arrangement, crystallographic characteristics and
fatigue crack initiation of deformation bands have been investigated using a
technique whereby the surface of metal specimens can be examined by
transmission electron microscopy. ie, the specimens are prepared by thinning
from one side only, so that one original face is retained. In this way surface
markings, such as slip lines can be seen at the same time as the dislocation
and other defects just below the surface of the metal. The mechanical test have been performed under strain controlled
conditions with a total strain of Δεt = 0.8 % and strain rate dε/dt =
3 x10 -3 s-1.These tests have been carried out at different number of cycles and the surface
damage has been monitored by optical microscopy using differential interference
contrast technique, scanning electron microscopy (SEM) and transmission
electron microscopy (TEM).In this way the propagation of slips lines from austenitic phase to
ferritic phase, intensive deformation bands and the formation of persistent
slip bands (PSBs), formation of short cracks and propagation of stage-I cracks
were observed.