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Title: Use of EBSD data in mesoscale numerical analyses

Abstract

Experimentation, theory, and modeling have all played vital roles in defining what is known about microstructural evolution and the effects of microstructure on material properties. Recently, technology has become an enabling factor, allowing significant advances to be made on several fronts. Experimental evidence of crystallographic slip and the basic theory of crystal plasticity were established in the early 20th century, and the theory and models evolved incrementally over the next 60 years. During this time, modeling was primarily concerned with the average response of polycrystalline aggregates. While some detailed finite element modeling (FEM) with crystal plasticity constitutive relations was performed in the early 1980's, such simulations over taxed the capacity of the available computer hardware. Advances in computer capabilities led to a flurry of activity in finite element modeling in the next 10 years, thus increasing understanding of lattice orientation evolution and generating detailed predictions of spatial orientation distributions that could not be readily validated with existing experimental characterization methods. Significant advancements in material characterization, particularly automated electron backscatter diffraction (EBSD), have made it possible to conduct detailed validation studies of the FEM predictions. The data collected are extensive, and many questions about the evolution of microstructure and its rolemore » in determining mechanical properties can now be addressed. It is now possible to obtain a detailed map of lattice orientations on a fine size scale. This will allow detailed quantitative comparisons of experiments and newly emerging large scale continuum FEM simulations. This capability will facilitate model validation efforts aimed at predicting deformation induced structural features, such as shear bands and cell structures, as well as predictions of the effects of grain interactions. The insight gained from the coupling of EBSD and FEM studies will provide impetus for further development of microstructure models and theories of microstructure evolution. Early studies connecting EBSD data to detailed finite element models used manual measurements to define initial orientations for the simulations. In one study, manual measurements of the deformed structure were also obtained for comparison with the model predictions. More recent work has taken advantage of automated data collection on deformed specimens as a means of collecting detailed and spatially correlated data for FEM model validation. Although it will not be discussed here, EBSD data can also be incorporated in FEM analyses in a less direct manner that is suitable for simulations where the element size is much larger than the grain size. The purpose of such models is to account for the effects of evolving material anisotropy in macro-scale simulations. In these analyses, a polycrystal plasticity model (e.g., a Taylor model or a self-consistent model), or a yield surface constructed from a polycrystal plasticity model, is used to determine the constitutive response of each element. The initial orientations used in the polycrystal plasticity model can be obtained from EBSD analyses or by fitting distributions of discrete orientations to x-ray data. The use of EBSD data is advantageous in that it is easier to account for spatial gradients of orientation distribution within a part. Another area in which EBSD data is having a great impact is on recrystallization modeling. EBSD techniques can be used to collect data for quantitative microstructural analysis (Humphreys, 1998). This data can be used to infer growth kinetics of specific orientations, and this information can be synthesized into more accurate grain growth or recrystallization models (Vogel et al., 1996). A second role which EBSD techniques may play in recrystallization modeling is in determining initial structures for the models. A realistic starting structure is vital for evaluating the models, and attempts at predicting realistic structures with finite element simulations are not yet successful. As methodologies and equipment resolution continue to improve, it is possible that measured structures will serve as input for recrystallization models. Simulations have already been run using information obtained manually from a TEM.« less

Authors:
;
Publication Date:
Research Org.:
Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
15013398
Report Number(s):
UCRL-JC-137195-REV-1
TRN: US200604%%74
DOE Contract Number:  
W-7405-ENG-48
Resource Type:
Conference
Resource Relation:
Conference: American Society of Metals Conference Minerals, Metals, Materials Society, St. Louis, MO, Oct 08 - Oct 12, 2000
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ANISOTROPY; DEFORMATION; DIFFRACTION; ELECTRONS; GRAIN GROWTH; GRAIN SIZE; KINETICS; MECHANICAL PROPERTIES; MICROSTRUCTURE; ORIENTATION; PLASTICITY; POLYCRYSTALS; RECRYSTALLIZATION; RESOLUTION; SHEAR; SLIP; VALIDATION

Citation Formats

Becker, R, and Wiland, H. Use of EBSD data in mesoscale numerical analyses. United States: N. p., 2000. Web. doi:10.1007/978-1-4757-3205-4_16.
Becker, R, & Wiland, H. Use of EBSD data in mesoscale numerical analyses. United States. https://doi.org/10.1007/978-1-4757-3205-4_16
Becker, R, and Wiland, H. 2000. "Use of EBSD data in mesoscale numerical analyses". United States. https://doi.org/10.1007/978-1-4757-3205-4_16. https://www.osti.gov/servlets/purl/15013398.
@article{osti_15013398,
title = {Use of EBSD data in mesoscale numerical analyses},
author = {Becker, R and Wiland, H},
abstractNote = {Experimentation, theory, and modeling have all played vital roles in defining what is known about microstructural evolution and the effects of microstructure on material properties. Recently, technology has become an enabling factor, allowing significant advances to be made on several fronts. Experimental evidence of crystallographic slip and the basic theory of crystal plasticity were established in the early 20th century, and the theory and models evolved incrementally over the next 60 years. During this time, modeling was primarily concerned with the average response of polycrystalline aggregates. While some detailed finite element modeling (FEM) with crystal plasticity constitutive relations was performed in the early 1980's, such simulations over taxed the capacity of the available computer hardware. Advances in computer capabilities led to a flurry of activity in finite element modeling in the next 10 years, thus increasing understanding of lattice orientation evolution and generating detailed predictions of spatial orientation distributions that could not be readily validated with existing experimental characterization methods. Significant advancements in material characterization, particularly automated electron backscatter diffraction (EBSD), have made it possible to conduct detailed validation studies of the FEM predictions. The data collected are extensive, and many questions about the evolution of microstructure and its role in determining mechanical properties can now be addressed. It is now possible to obtain a detailed map of lattice orientations on a fine size scale. This will allow detailed quantitative comparisons of experiments and newly emerging large scale continuum FEM simulations. This capability will facilitate model validation efforts aimed at predicting deformation induced structural features, such as shear bands and cell structures, as well as predictions of the effects of grain interactions. The insight gained from the coupling of EBSD and FEM studies will provide impetus for further development of microstructure models and theories of microstructure evolution. Early studies connecting EBSD data to detailed finite element models used manual measurements to define initial orientations for the simulations. In one study, manual measurements of the deformed structure were also obtained for comparison with the model predictions. More recent work has taken advantage of automated data collection on deformed specimens as a means of collecting detailed and spatially correlated data for FEM model validation. Although it will not be discussed here, EBSD data can also be incorporated in FEM analyses in a less direct manner that is suitable for simulations where the element size is much larger than the grain size. The purpose of such models is to account for the effects of evolving material anisotropy in macro-scale simulations. In these analyses, a polycrystal plasticity model (e.g., a Taylor model or a self-consistent model), or a yield surface constructed from a polycrystal plasticity model, is used to determine the constitutive response of each element. The initial orientations used in the polycrystal plasticity model can be obtained from EBSD analyses or by fitting distributions of discrete orientations to x-ray data. The use of EBSD data is advantageous in that it is easier to account for spatial gradients of orientation distribution within a part. Another area in which EBSD data is having a great impact is on recrystallization modeling. EBSD techniques can be used to collect data for quantitative microstructural analysis (Humphreys, 1998). This data can be used to infer growth kinetics of specific orientations, and this information can be synthesized into more accurate grain growth or recrystallization models (Vogel et al., 1996). A second role which EBSD techniques may play in recrystallization modeling is in determining initial structures for the models. A realistic starting structure is vital for evaluating the models, and attempts at predicting realistic structures with finite element simulations are not yet successful. As methodologies and equipment resolution continue to improve, it is possible that measured structures will serve as input for recrystallization models. Simulations have already been run using information obtained manually from a TEM.},
doi = {10.1007/978-1-4757-3205-4_16},
url = {https://www.osti.gov/biblio/15013398}, journal = {},
number = ,
volume = ,
place = {United States},
year = {2000},
month = {3}
}

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Works referenced in this record:

Three-dimensional deformation process simulation with explicit use of polycrystal plasticity models
journal, January 1993


An analysis of nonuniform and localized deformation in ductile single crystals
journal, June 1982


XLVI. A theory of the plastic distortion of a polycrystalline aggregate under combined stresses.
journal, April 1951


Computational modelling of single crystals
journal, April 1993


Latent Hardening in Single Crystals II. Analytical Characterization and Predictions
journal, October 1991


Crystal Plasticity
journal, December 1983


Finite element model of plastically deformed multicrystal
journal, January 1990


Shear band formation in plane strain compression
journal, September 1988


The plastic extension and fracture of aluminium crystals
journal, May 1925

  • Taylor, Geoffrey Ingram; Elam, C. R.
  • Proceedings of the Royal Society of London. Series A, Containing Papers of a Mathematical and Physical Character, Vol. 108, Issue 745, p. 28-51
  • https://doi.org/10.1098/rspa.1925.0057

The variational formulation of viscoplastic constitutive updates
journal, April 1999


Flow localization in the plane strain tensile test
journal, April 1981


High strain-rate localization and failure of crystalline materials
journal, December 1990


Single Crystal Hardening
journal, May 1990


Constitutive analysis of elastic-plastic crystals at arbitrary strain
journal, December 1972


Crack tip fields in a material with three independent slip systems: NiAl single crystal
journal, October 1992


Plastic deformation of b.c.c. polycrystals
journal, February 1964


A computational procedure for rate-independent crystal plasticity
journal, April 1996


Analysis of an aluminum single crystal with unstable initial orientation (001) [110] in channel die compression
journal, January 1991


Effect of texture on the development of grain size distribution during normal grain growth
journal, April 1996


Crystallographic texture evolution in bulk deformation processing of FCC metals
journal, January 1992


Quantitative metallography by electron backscattered diffraction
journal, September 1999


Röntgenographische Bestimmung von Kristallanordnungen
journal, April 1922


Mode mixity effects on crack tip deformation in ductile single crystals
journal, August 1992


An Analysis of Shear Localization During Bending of a Polycrystalline Sheet
journal, September 1992


Analysis of ridging in aluminum auto body sheet metal
journal, September 1998


Effects of grain interactions on deformation and local texture in polycrystals
journal, July 1995


Material rate dependence and localized deformation in crystalline solids
journal, December 1983


Non-schmid yield behavior in single crystals
journal, May 1992