J. Appl. Cryst.の発刊に際して

Mechanical properties of nanocrystalline materials

Perspectives on Titanium Science and Technology

The current understanding of the fundamentals of recrystallization is summarized. This includes understanding the as-deformed state. Several aspects of recrystallization are described: nucleation and growth, the development of misorientation during deformation, continuous, dynamic, and geometric dynamic recrystallization, particle effects, and texture. This article is authored by the leading experts in these areas. The subjects are discussed individually and recommendations for further study are listed in the final section.

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Current issues in recrystallization: a review

Dynamic and post-dynamic recrystallization under hot, cold and severe plastic deformation conditions

List of Contributors. 1. The Development of Automated Diffraction in Scanning and Transmission Electron Microscopy D.J. Dingley. 2. Theoretical Framework for Electron Backscatter Diffraction V. Randle. 3. Representation of Texture in Orientation Space K. Rajan. 4. Rodriques-Frank Representations of Crystallographic Texture K. Rajan. 5. Fundamentals of Automated EBSD S.I. Wright. 6. Studies on the Accuracy of Electron Backscatter Diffraction Measurements M.C. Demirel, B.S. El-Dasher, B.L. Adams, A.D. Rollett. 7. Phase Identification Using Electron Backscatter Diffraction in the Scanning Electron Microscope J.R. Michael. 8. Three-Dimensional Orientation Imaging D.J. Jensen. 9. Automated Electron Backscatter Diffraction: Present State and Prospects R.A. Schwarzer. 10. EBSD: Buying a Systems A. Eades. 11. Hardware and Software Optimization for Orientation Mapping and Phase Identification P.P. Camus. 12. An Automated EBSD Acquisition and Processing System P. Rolland, K.G. Dicks. 13. Advanced Software Capabilities for Automated EBSD S.I. Wright, D.P. Field, D.J. Dingley. 14. Strategies for Analysis of EBSD Datasets W.E. King, J.S. Stolken, M. Kumar, A.J. Schwartz. 15. Structure-Property Relations: EBSD-Based Materials-Sensitive Design B.L. Adams, B.L. Henrie, L.L. Howell, R.J. Balling. 16. Use of EBSD Data in Mesoscale Numerical Analyses R. Becker, H. Weiland. 17. Characterization of Deformed Microstructures D.P. Field, H. Weiland. 18. Anisotropic Plasticity Modeling Incorporating EBSD Characterization of Tantalum and Zirconium J.F. Bingert, G.C. Kaschner, T.A. Mason, P.J. Maudlin, G.T. Gray III. 19. Measuring Strains Using Electron Backscatter Diffraction A.J. Wilkinson. 20. Mapping Residual Plastic Strain in Materials Using Electron Backscatter Diffraction E.M. Lehockey, Yang-Pi Lin, O.E. Lepik. 21.EBSD Contra TEM Characterization of a Deformed Aluminum Single Crystal Xiaoxu Huang, D.J. Jensen. 22. Continuous Recrystallization and Grain Boundaries in a Superplastic Aluminum Alloy T.R. McNelley. 23. Analysis of Facets and Other Surfaces Using Electron Backscatter Diffraction V. Randle. 24. EBSD of Ceramic Materials J.K. Farrer, J.R. Michael, C.B. Carter. 25. Grain Boundary Character Based Design of Polycrystalline High Temperature Superconducting Wires A. Goyal. Index.

Electron Backscatter Diffraction in Materials Science

A new microscopy, called orientation imaging microscopy, is described. Imaging results from precise measurements of local lattice orientation facilitated by backscattered Kikuchi diffraction. The hardware configuration of the microscope is described, and a formal description of image formation is developed. Application of the method to several cubic materials and material conditions is described. Emphasis is given to those areas of application where new insight into polycrystalline microstructures has begun to emerge.

Orientation imaging: The emergence of a new microscopy

The accelerating rate at which new materials are appearing, and transforming the engineering world, only serves to emphasize the vast potential for novel material structure, and related performance. Microstructure-sensitive design (MSD) aims at providing inverse design methodologies that facilitate design of material internal structure for performance optimization. Spectral methods are applied across the structure, property and processing design spaces in order to compress the computational requirements for linkages between the spaces and enable inverse design. Research has focused mainly on anisotropic, polycrystalline materials, where control of local crystal orientation can result in a broad range of property combinations. This review presents the MSD framework in the context of both the engineering advances that have led to its creation, and those that complement or provide alternative methods for design of materials (meaning ‘optimization of material structure’ in this context). A variety of definitions for the structure of materials are presented, with an emphasis on correlation functions; and spectral methods are introduced for compact descriptions and efficient computations. The microstructure hull is defined as the design space for structure in the spectral framework. Reconstruction methods provide invertible links between statistical descriptions of structure, and deterministic instantiations. Subsequently, structure–property relations are reviewed, and again subjected to representation via spectral methods. The concept of a property closure is introduced as the design space for performance optimization, and methods for moving between the closures and hulls are presented as the basis for the subsequent discussion on microstructure design. Finally, the spectral framework is applied to deformation processes, and methodologies that facilitate process design are reviewed.

Microstructure Sensitive Design for Performance Optimization

Reported here is a study of the pattern of lattice curvature near the interface of deformed high-purity aluminium (99.9999%) bicrystals of specified crystallographic character (large-angle random). Curvature data are obtained from electron back-scattering diffraction pattern observations using orientation imaging microscopy. The concept of geometrically necessary dislocations (GNDs) is used as the central tool in the description of the observations. The samples studied were channel-die compressed perpendicular to the interface to plastic strain levels of 0.1 and 0.3. At a strain level of 0.1 the primary observation is the development of a pile-up of GNDs (i.e. lattice curvature) near the interface. At the higher strain level of 0.3, however, a dramatic change in the distribution is observed. The nature of this change suggests that the interface has absorbed (or emitted) some components of the nearby GND field. with an accompanying change in the local character of the interface towards a broader d...

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Observations of lattice curvature near the interface of a deformed aluminium bicrystal

Recent advances both in experimental instrumentation and computing power have made it possible to interrogate the distribution of internal interfaces in polycrystals and the three dimensional structure of the grain boundary network with an unprecedented level of detail. The purpose of this paper is to review techniques that can be used to study the mesoscopic crystallographic structure of grain boundary networks and to summarize current findings. Recent studies have shown that grain surfaces within dense polycrystals favor the same low energy planes that are found on equilibrium crystal shapes and growth forms of crystals in contact with another phase. In the materials for which comprehensive data exists, the distribution of grain boundaries is inversely correlated to the sum of the energies of the surfaces of the grains on either side of the boundary.

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Brent L. Adams

Papers

Electron Backscatter Diffraction in Materials Science

Orientation imaging: The emergence of a new microscopy

Microstructure Sensitive Design for Performance Optimization

Observations of lattice curvature near the interface of a deformed aluminium bicrystal

The Distribution of Internal Interfaces in Polycrystals