55 research outputs found
Evolution of Microstructure and Texture during Warm Rolling Of a Duplex Steel
The effect of warm rolling on the evolution of microstructure and texture in a duplex stainless steel (DSS) was investigated. For this purpose, a DSS steel was warm rolled up to 90 pct reduction in thickness at 498 K, 698 K, and 898 K (225 °C, 425 °C, and 625 °C). The microstructure with an alternate arrangement of deformed ferrite and austenite bands was observed after warm rolling; however, the microstructure after 90 pct warm rolling at 498 K and 898 K (225 °C and 625 °C) was more lamellar and uniform as compared to the rather fragmented and inhomogeneous structure observed after 90 pct warm rolling at 698 K (425 °C). The texture of ferrite in warm-rolled DSS was characterized by the presence of the RD (〈011〉//RD) and ND (〈111〉//ND) fibers. However, the texture of ferrite in DSS warm rolled at 698 K (425 °C) was distinctly different having much higher fraction of the RD-fiber components than that of the ND-fiber components. The texture and microstructural differences in ferrite in DSS warm rolled at different temperatures could be explained by the interaction of carbon atoms with dislocations. In contrast, the austenite in DSS warm rolled at different temperatures consistently showed pure metal- or copper-type deformation texture which was attributed to the increase in stacking fault energy at the warm-rolling temperatures. It was concluded that the evolution of microstructure and texture of the two constituent phases in DSS was greatly affected by the temperature of warm rolling, but not significantly by the presence of the other phas
Unraveling the temperature dependence of the yield strength in single-crystal tungsten using atomistically-informed crystal plasticity calculations
We use a physically-based crystal plasticity model to predict the yield
strength of body-centered cubic (bcc) tungsten single crystals subjected to
uniaxial loading. Our model captures the thermally-activated character of screw
dislocation motion and full non-Schmid effects, both of which are known to play
a critical role in bcc plasticity. The model uses atomistic calculations as the
sole source of constitutive information, with no parameter fitting of any kind
to experimental data. Our results are in excellent agreement with experimental
measurements of the yield stress as a function of temperature for a number of
loading orientations. The validated methodology is then employed to calculate
the temperature and strain-rate dependence of the yield strength for 231
crystallographic orientations within the standard stereographic triangle. We
extract the strain-rate sensitivity of W crystals at different temperatures,
and finish with the calculation of yield surfaces under biaxial loading
conditions that can be used to define effective yield criteria for engineering
design models
Finite element simulations of the plastic behaviour of crystallin aggregates, potential applications to salt and calcite
No abstract provide
Plastic behavior of prestrained metals: microstructural aspects.
No abstract availabl
Finite element simulations of the deformation of bcc aggregates using a crystal plasticity model
No abstract provide
Finite element simulation of the deformation of b.c.c. aggregates using a crystal plasticity model - local orientation effects
No abstract provide
Newtonian flow of heterogeneous synthetic gabbros at high strain: Grain sliding, ductile failure, and contrasting local mechanisms and interactions
International audienc
Apport des mesures de champs par corrélation d’images pour l’étude de la déformation de géomatériaux
International audienc
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