The Experts below are selected from a list of 251928 Experts worldwide ranked by ideXlab platform
Jean Marc Olive - One of the best experts on this subject based on the ideXlab platform.
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effects of microstructure and local mechanical fields on intergranular stress corrosion cracking of a friction stir welded aluminum copper lithium 2050 nugget
Corrosion Science, 2014Co-Authors: Matthieu Dhondt, Isabelle Aubert, Nicolas Saintier, Jean Marc OliveAbstract:Abstract The effects of the microstructure and mechanical fields on intergranular stress corrosion cracking (IGSCC) of the nugget zone of heat treated welds obtained by friction stir welding in the AA2050 aluminum alloy have been investigated at different scales. At low strain rate, in 1.0 NaCl aqueous solution, IGSCC develops in the microstructure, whereas only pitting corrosion is observed without any mechanical stress. Based on surface observations, EBSD analysis and X-ray tomography, the key role of sub-millimetric textured bands (induced by the welding process) on the IGSCC is demonstrated. Analyses at a more local scale show the grain Boundary (low angle Boundary, special coincident site lattice Boundary or high angle Boundary) do not have a significant effect on crack initiation. Crystal plasticity finite element calculations show that the threshold normal stress at grain boundaries for IGSCC development is about 80% of the macroscopic stress. It is also highlighted by crystal plasticity calculations that there is a drastic effect of the local stress field on the shape of cracks. Finally, it is shown that plasticity induced residual stresses are sufficient for the formation of IGSCC.
Matthieu Dhondt - One of the best experts on this subject based on the ideXlab platform.
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effects of microstructure and local mechanical fields on intergranular stress corrosion cracking of a friction stir welded aluminum copper lithium 2050 nugget
Corrosion Science, 2014Co-Authors: Matthieu Dhondt, Isabelle Aubert, Nicolas Saintier, Jean Marc OliveAbstract:Abstract The effects of the microstructure and mechanical fields on intergranular stress corrosion cracking (IGSCC) of the nugget zone of heat treated welds obtained by friction stir welding in the AA2050 aluminum alloy have been investigated at different scales. At low strain rate, in 1.0 NaCl aqueous solution, IGSCC develops in the microstructure, whereas only pitting corrosion is observed without any mechanical stress. Based on surface observations, EBSD analysis and X-ray tomography, the key role of sub-millimetric textured bands (induced by the welding process) on the IGSCC is demonstrated. Analyses at a more local scale show the grain Boundary (low angle Boundary, special coincident site lattice Boundary or high angle Boundary) do not have a significant effect on crack initiation. Crystal plasticity finite element calculations show that the threshold normal stress at grain boundaries for IGSCC development is about 80% of the macroscopic stress. It is also highlighted by crystal plasticity calculations that there is a drastic effect of the local stress field on the shape of cracks. Finally, it is shown that plasticity induced residual stresses are sufficient for the formation of IGSCC.
Isabelle Aubert - One of the best experts on this subject based on the ideXlab platform.
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effects of microstructure and local mechanical fields on intergranular stress corrosion cracking of a friction stir welded aluminum copper lithium 2050 nugget
Corrosion Science, 2014Co-Authors: Matthieu Dhondt, Isabelle Aubert, Nicolas Saintier, Jean Marc OliveAbstract:Abstract The effects of the microstructure and mechanical fields on intergranular stress corrosion cracking (IGSCC) of the nugget zone of heat treated welds obtained by friction stir welding in the AA2050 aluminum alloy have been investigated at different scales. At low strain rate, in 1.0 NaCl aqueous solution, IGSCC develops in the microstructure, whereas only pitting corrosion is observed without any mechanical stress. Based on surface observations, EBSD analysis and X-ray tomography, the key role of sub-millimetric textured bands (induced by the welding process) on the IGSCC is demonstrated. Analyses at a more local scale show the grain Boundary (low angle Boundary, special coincident site lattice Boundary or high angle Boundary) do not have a significant effect on crack initiation. Crystal plasticity finite element calculations show that the threshold normal stress at grain boundaries for IGSCC development is about 80% of the macroscopic stress. It is also highlighted by crystal plasticity calculations that there is a drastic effect of the local stress field on the shape of cracks. Finally, it is shown that plasticity induced residual stresses are sufficient for the formation of IGSCC.
Nicolas Saintier - One of the best experts on this subject based on the ideXlab platform.
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effects of microstructure and local mechanical fields on intergranular stress corrosion cracking of a friction stir welded aluminum copper lithium 2050 nugget
Corrosion Science, 2014Co-Authors: Matthieu Dhondt, Isabelle Aubert, Nicolas Saintier, Jean Marc OliveAbstract:Abstract The effects of the microstructure and mechanical fields on intergranular stress corrosion cracking (IGSCC) of the nugget zone of heat treated welds obtained by friction stir welding in the AA2050 aluminum alloy have been investigated at different scales. At low strain rate, in 1.0 NaCl aqueous solution, IGSCC develops in the microstructure, whereas only pitting corrosion is observed without any mechanical stress. Based on surface observations, EBSD analysis and X-ray tomography, the key role of sub-millimetric textured bands (induced by the welding process) on the IGSCC is demonstrated. Analyses at a more local scale show the grain Boundary (low angle Boundary, special coincident site lattice Boundary or high angle Boundary) do not have a significant effect on crack initiation. Crystal plasticity finite element calculations show that the threshold normal stress at grain boundaries for IGSCC development is about 80% of the macroscopic stress. It is also highlighted by crystal plasticity calculations that there is a drastic effect of the local stress field on the shape of cracks. Finally, it is shown that plasticity induced residual stresses are sufficient for the formation of IGSCC.
A Pineau - One of the best experts on this subject based on the ideXlab platform.
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cyclically induced softening due to low angle Boundary annihilation in a martensitic steel
Materials Science and Engineering A-structural Materials Properties Microstructure and Processing, 2005Co-Authors: Maxime Sauzay, Helene Brillet, I Monnet, Michel Mottot, Francoise Barcelo, Benjamin Fournier, A PineauAbstract:Martensitic steels are known for their softening during cyclic tests carried out at high temperature. The softening has been at least partially explained by lath and sub-grain Boundary elimination. This article is dedicated to an attempt at modelling both phenomena. Thanks to mechanical tests it is shown that the softening is mainly due to a decrease of the backstress. Transmission electron microscopy allows us to propose a mechanism of Low-Angle Boundary elimination. Annihilation between dislocations of Low-Angle boundaries and incident mobile dislocations is modelled. The macroscopic backstress is finally computed using a Hall–Petch law and the Taylor model.
