TY - JOUR
T1 - Investigation of the stress fields around a fatigue crack in aluminium alloy 5091
AU - Rahman, M
AU - Fitzpatrick, M E
AU - Edwards, L
AU - Pratihar, S
AU - Peel, MJ
AU - Steuwer, A
AU - Buslaps, T
PY - 2008
Y1 - 2008
N2 - There have been many theoretical studies to predict the stress fields around the tip of a
growing fatigue crack. However, until recently the highly-localized, small scale nature of the
stresses has meant that direct measurement has not been possible. With the current generation of
synchrotron X-ray sources, sub-millimetre sampling dimensions are now possible, and it has
become possible to evaluate directly the stresses at the tip of a fatigue crack and to see how the
stresses evolve as the result of an overload, for example.
In this paper we present results of synchrotron X-ray diffraction analysis of the stress fields
around a fatigue crack in aluminium alloy 5091 (Al-Mg-Li-C-O); this is a dispersion-strengthened
alloy with a fine grain size, which makes it ideal for such experiments. Compact tension (CT)
specimens were prepared with constant amplitude fatigue loading. The energy dispersive X-ray
diffraction (EDXRD) technique was used for measuring strains around the crack tip along the mid
thickness of the specimen under in-situ loading. The measurement was carried out at the ESRF
(European Synchrotron Radiation Facility), Grenoble, France on the ID15A beam line. The
experimental crack tip stresses have been compared with the analytical fracture mechanics solution.
AB - There have been many theoretical studies to predict the stress fields around the tip of a
growing fatigue crack. However, until recently the highly-localized, small scale nature of the
stresses has meant that direct measurement has not been possible. With the current generation of
synchrotron X-ray sources, sub-millimetre sampling dimensions are now possible, and it has
become possible to evaluate directly the stresses at the tip of a fatigue crack and to see how the
stresses evolve as the result of an overload, for example.
In this paper we present results of synchrotron X-ray diffraction analysis of the stress fields
around a fatigue crack in aluminium alloy 5091 (Al-Mg-Li-C-O); this is a dispersion-strengthened
alloy with a fine grain size, which makes it ideal for such experiments. Compact tension (CT)
specimens were prepared with constant amplitude fatigue loading. The energy dispersive X-ray
diffraction (EDXRD) technique was used for measuring strains around the crack tip along the mid
thickness of the specimen under in-situ loading. The measurement was carried out at the ESRF
(European Synchrotron Radiation Facility), Grenoble, France on the ID15A beam line. The
experimental crack tip stresses have been compared with the analytical fracture mechanics solution.
U2 - 10.4028/www.scientific.net/MSF.571-572.119
DO - 10.4028/www.scientific.net/MSF.571-572.119
M3 - Article (Academic Journal)
VL - 571-572
SP - 119
EP - 124
JO - Materials Science Forum - Silicon Carbide and Related Materials 2005
JF - Materials Science Forum - Silicon Carbide and Related Materials 2005
SN - 0255-5476
ER -