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Local and near surface structure from diffraction
Materials Science and Engineering A 528 (2010) 1–2
Contents lists available at ScienceDirect
Materials Science and Engineering A journal homepage: www.elsevier.com/locate/msea
Preface
Local and near surface structure from diffraction a r t i c l e Keywords: X-ray diffraction Neutron diffraction Materials structure
i n f o
a b s t r a c t This special topic of Materials Science and Engineering A highlights novel applications of X-ray and neutron diffraction for the analysis of a range of materials, including conventional and nanostructured materials, thin films, bio-inspired materials, and superalloys. The development of ultra-brilliant synchrotron X-ray sources and recent advances in neutron diffraction provide important new opportunities for the analysis of local and near surface material structures at multiple length scales. © 2010 Elsevier B.V. All rights reserved.
The special topic starts with a group of papers focused on texture analysis in conventional materials. The manuscript by Barabash et al. demonstrates the combined application of neutron and Xray synchrotron microdiffraction in transmission and reflection geometries for the analysis of texture evolution in a Ni-based superalloy over gauge volumes ranging from hundreds of cubic millimeters down to sub cubic micrometers. The various measurements complement each other by probing texture at different length scales. It is shown that inhomogeneous subgrain dislocation arrangements evolve into the overall texture development at the macroscale. The group of Prof. Liss describes the use of well-collimated, high-energy 90 keV X-rays to study metals undergoing plastic deformation. The in-situ real-time synchrotron measurements of course-grained bulk samples show evidence for subgrain formation, grain rotation, grain refinement and the evolution from a single grain into the asymptotic texture. Lattice strain, its partition and anisotropy are simultaneously revealed. Dr. Pang and co-workers present an application of polychromatic X-ray microdiffraction to study the role of crystallographic orientation and surface proximity in the self-similar behavior of deformed Cu single crystals. They measured spatial correlations of the local lattice rotations in tensile-deformed Cu single crystals oriented with [1 2 3], [1 1 1] and [0 0 1] axes parallel to the tensile axis. Their measurements illuminate the transition from surface-like to bulk-like deformation behavior and provide new quantitative information to guide emerging models of self-organized structures in plasticity. An evaluation of the Gamma Prime volume fraction and lattice misfits in a nickel base superalloy using the external standard X-ray diffraction method is presented by the group of Dr. Tiley. The authors used extraction techniques to provide unconstrained ␥ -phase powders for both water quenched and slow cooled samples that were aged at 760 ◦ C for 0, 25, 50, 100, and 200 h. Texture characterization in bio-inspired materials is described in the manuscript from Prof. Chateigner’s group. They used Xray diffraction to study texture in a variety of bio-materials: from 0921-5093/$ – see front matter © 2010 Elsevier B.V. All rights reserved. doi:10.1016/j.msea.2010.08.065
biomineralisation to prosthetics via mollusc phylogeny. Strong textures of mollusc shell layers are utilized to provide phylogenetic information. Aragonitic and calcitic layers are the targets in their study, inside which nacre layers play an important role. The textural information is used to provide a precise structural determination of the biogenic aragonite. Such information provides useful insights into biomineralisation processes. The second group of papers demonstrates the application of diffraction to the analysis of thin films, layered structures and nanomaterials. The combined experimental-modelling study of lattice rotations and deviatoric strain gradients induced by focused-ion beam (FIB) milling in nitride heterostructures is presented in the paper by Barabash et al. The authors demonstrate that FIB milling causes both direct and indirect damage to the InGaN/GaN layers. This manuscript is followed by the manuscript from the group of Prof. Krost, which shows the use of in-situ curvature and X-ray measurements to evaluate the metal organic vapor phase growth process of distributed Bragg reflectors consisting of an AlInN/GaN system. The authors discuss the strain induced by thermal mismatch and lattice mismatch for an example of the Bragg mirror multilayer AlInN/GaN on a sapphire substrate. A comparative study of microstructure evolution during selfannealing and thermal annealing of nanocrystalline electrodeposits is described in the manuscript by Pantleon and Somers. These realtime studies of evolving microstructure in copper, silver and nickel electrodeposits used time-resolved X-ray diffraction line profile analysis and crystallographic texture analysis. Measurements were made during room temperature storage and during isothermal annealing at elevated temperatures. These in-situ studies – with time resolution – quantified the self-annealing kinetics of copper and silver electrodeposits as well as the annealing kinetics of electrodeposited nickel. The group of Prof. Brock reviewed real-time X-ray diffuse scattering studies of the evolving structure of complex oxide thin films during pulsed laser deposition in the layer-by-layer growth mode. These measurements provide detailed structural information on the time- and length scales relevant for growth kinetics.
2
Preface / Materials Science and Engineering A 528 (2010) 1–2
Properties of nanocrystallinne ceria domains are studied by insitu isothermal X-ray diffraction in the manuscript by from Prof. Scardi’s group. They interpreted the observed process in terms of coalescence of the existing nuclei. Using X-ray powder diffraction, the manuscript by Beyerlein et al. characterized (1 1 1) surface tailored Pt nanoparticles. They employed whole powder pattern modelling (WPPM) of the measured X-ray diffraction pattern to obtain statistical information on the particle sizes and shapes present in the sample. Ultra-small angle X-ray scattering (USAXS) was used in the paper by Bacciochini et al. for quantification of void network architectures of suspension plasma sprayed (SPS) yttria-stabilized zirconia (YSZ) coatings. They concluded that the combination of USAXS, helium pycnometry, and scanning electron microscopy (SEM), provide sufficient details to understand the void network architectures. Based on high-resolution tomographic reconstructions the manuscript by Sket et al. describes the size, shape and spatial distribution of voids along a notch radius. They show that the spatial distribution of void density has a strong correlation with stress triaxiality, maximum principal stress and the equivalent von Mises stress. An analysis of the size distribution of non-coalesced voids in terms of general power-law functions, describing nucleation and growth, indicates that void growth in E911 steel is dominated by the constrained diffusion mechanism. Applications of neutron diffraction to microstructure and defect characterization are described by the next group of papers. The general approach of line profile analysis with neutron and Xray data is described in the manuscript by Ribarik and Ungar. They described an “extended convolutional multiple whole profile” (eCMWP) software package. The application of the software package is demonstrated through the microstructure determination in a variety of polycrystalline and single crystals specimens with various texture. The manuscript by Balzar et al. reports the complete macroscopic average strain and stress tensors for a cold-rolled uranium plate, based on the neutron time of flight (TOF) measurements. The tensor analysis is based on a least-squares refinement of the interplanar spacings of 19 Bragg reflections.
Using small angle neutron scattering (SANS), Fan et al. studied the effects of molecular weight, temperature and salt on the selfassembly of triblock copolymer solutions. From SANS the authors obtained information on the size of the core and corona, intermicelle distance, aggregation number and the volume fraction of the micelles. Their study finds that temperature, polymer molecular weight and sodium carbonate concentration all have a strong influence on the phase behavior of the triblock copolymers. An in-situ neutron diffraction study on decomposition of Ti2 AlN at 1500–1800 ◦ C in vacuum is described in the paper of Pang et al. Complementory depth-profiling of near surface composition and examination of the cross-sectional microstructures of decomposed Ti2 AlN, were conducted using grazing-incidence synchrotron radiation diffraction and SEM. These measurements support neutron diffraction results that show decomposition proceeding primarily via sublimation of Al from grain surfaces. In summary, this collection of papers is a sampling of the emerging body of research that exploits powerful new neutron and X-ray diffraction capabilities. The combination of small beams, high flux synchrotron radiation, new neutron techniques and advanced computer reconstruction, allows researchers to obtain unique new information about local and near surface structure at different length scales. Guest Editor Rozaliya I. Barabash a,b,∗ Guest Editor Gene E. Ice a a MST Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831-6118, USA b Materials Science and Engineering Department, University of Tennessee, Knoxville, TN 37996, USA ∗ Corresponding
author at: MST Division, Oak Ridge National Laboratory, One Bethel valley Road, Oak Ridge, TN 37831-6118, USA. Tel.: +1 865 2417230; fax: +1 865 5747659. E-mail address: [email protected] (R.I. Barabash)
Contents lists available at ScienceDirect
Materials Science and Engineering A journal homepage: www.elsevier.com/locate/msea
Preface
Local and near surface structure from diffraction a r t i c l e Keywords: X-ray diffraction Neutron diffraction Materials structure
i n f o
a b s t r a c t This special topic of Materials Science and Engineering A highlights novel applications of X-ray and neutron diffraction for the analysis of a range of materials, including conventional and nanostructured materials, thin films, bio-inspired materials, and superalloys. The development of ultra-brilliant synchrotron X-ray sources and recent advances in neutron diffraction provide important new opportunities for the analysis of local and near surface material structures at multiple length scales. © 2010 Elsevier B.V. All rights reserved.
The special topic starts with a group of papers focused on texture analysis in conventional materials. The manuscript by Barabash et al. demonstrates the combined application of neutron and Xray synchrotron microdiffraction in transmission and reflection geometries for the analysis of texture evolution in a Ni-based superalloy over gauge volumes ranging from hundreds of cubic millimeters down to sub cubic micrometers. The various measurements complement each other by probing texture at different length scales. It is shown that inhomogeneous subgrain dislocation arrangements evolve into the overall texture development at the macroscale. The group of Prof. Liss describes the use of well-collimated, high-energy 90 keV X-rays to study metals undergoing plastic deformation. The in-situ real-time synchrotron measurements of course-grained bulk samples show evidence for subgrain formation, grain rotation, grain refinement and the evolution from a single grain into the asymptotic texture. Lattice strain, its partition and anisotropy are simultaneously revealed. Dr. Pang and co-workers present an application of polychromatic X-ray microdiffraction to study the role of crystallographic orientation and surface proximity in the self-similar behavior of deformed Cu single crystals. They measured spatial correlations of the local lattice rotations in tensile-deformed Cu single crystals oriented with [1 2 3], [1 1 1] and [0 0 1] axes parallel to the tensile axis. Their measurements illuminate the transition from surface-like to bulk-like deformation behavior and provide new quantitative information to guide emerging models of self-organized structures in plasticity. An evaluation of the Gamma Prime volume fraction and lattice misfits in a nickel base superalloy using the external standard X-ray diffraction method is presented by the group of Dr. Tiley. The authors used extraction techniques to provide unconstrained ␥ -phase powders for both water quenched and slow cooled samples that were aged at 760 ◦ C for 0, 25, 50, 100, and 200 h. Texture characterization in bio-inspired materials is described in the manuscript from Prof. Chateigner’s group. They used Xray diffraction to study texture in a variety of bio-materials: from 0921-5093/$ – see front matter © 2010 Elsevier B.V. All rights reserved. doi:10.1016/j.msea.2010.08.065
biomineralisation to prosthetics via mollusc phylogeny. Strong textures of mollusc shell layers are utilized to provide phylogenetic information. Aragonitic and calcitic layers are the targets in their study, inside which nacre layers play an important role. The textural information is used to provide a precise structural determination of the biogenic aragonite. Such information provides useful insights into biomineralisation processes. The second group of papers demonstrates the application of diffraction to the analysis of thin films, layered structures and nanomaterials. The combined experimental-modelling study of lattice rotations and deviatoric strain gradients induced by focused-ion beam (FIB) milling in nitride heterostructures is presented in the paper by Barabash et al. The authors demonstrate that FIB milling causes both direct and indirect damage to the InGaN/GaN layers. This manuscript is followed by the manuscript from the group of Prof. Krost, which shows the use of in-situ curvature and X-ray measurements to evaluate the metal organic vapor phase growth process of distributed Bragg reflectors consisting of an AlInN/GaN system. The authors discuss the strain induced by thermal mismatch and lattice mismatch for an example of the Bragg mirror multilayer AlInN/GaN on a sapphire substrate. A comparative study of microstructure evolution during selfannealing and thermal annealing of nanocrystalline electrodeposits is described in the manuscript by Pantleon and Somers. These realtime studies of evolving microstructure in copper, silver and nickel electrodeposits used time-resolved X-ray diffraction line profile analysis and crystallographic texture analysis. Measurements were made during room temperature storage and during isothermal annealing at elevated temperatures. These in-situ studies – with time resolution – quantified the self-annealing kinetics of copper and silver electrodeposits as well as the annealing kinetics of electrodeposited nickel. The group of Prof. Brock reviewed real-time X-ray diffuse scattering studies of the evolving structure of complex oxide thin films during pulsed laser deposition in the layer-by-layer growth mode. These measurements provide detailed structural information on the time- and length scales relevant for growth kinetics.
2
Preface / Materials Science and Engineering A 528 (2010) 1–2
Properties of nanocrystallinne ceria domains are studied by insitu isothermal X-ray diffraction in the manuscript by from Prof. Scardi’s group. They interpreted the observed process in terms of coalescence of the existing nuclei. Using X-ray powder diffraction, the manuscript by Beyerlein et al. characterized (1 1 1) surface tailored Pt nanoparticles. They employed whole powder pattern modelling (WPPM) of the measured X-ray diffraction pattern to obtain statistical information on the particle sizes and shapes present in the sample. Ultra-small angle X-ray scattering (USAXS) was used in the paper by Bacciochini et al. for quantification of void network architectures of suspension plasma sprayed (SPS) yttria-stabilized zirconia (YSZ) coatings. They concluded that the combination of USAXS, helium pycnometry, and scanning electron microscopy (SEM), provide sufficient details to understand the void network architectures. Based on high-resolution tomographic reconstructions the manuscript by Sket et al. describes the size, shape and spatial distribution of voids along a notch radius. They show that the spatial distribution of void density has a strong correlation with stress triaxiality, maximum principal stress and the equivalent von Mises stress. An analysis of the size distribution of non-coalesced voids in terms of general power-law functions, describing nucleation and growth, indicates that void growth in E911 steel is dominated by the constrained diffusion mechanism. Applications of neutron diffraction to microstructure and defect characterization are described by the next group of papers. The general approach of line profile analysis with neutron and Xray data is described in the manuscript by Ribarik and Ungar. They described an “extended convolutional multiple whole profile” (eCMWP) software package. The application of the software package is demonstrated through the microstructure determination in a variety of polycrystalline and single crystals specimens with various texture. The manuscript by Balzar et al. reports the complete macroscopic average strain and stress tensors for a cold-rolled uranium plate, based on the neutron time of flight (TOF) measurements. The tensor analysis is based on a least-squares refinement of the interplanar spacings of 19 Bragg reflections.
Using small angle neutron scattering (SANS), Fan et al. studied the effects of molecular weight, temperature and salt on the selfassembly of triblock copolymer solutions. From SANS the authors obtained information on the size of the core and corona, intermicelle distance, aggregation number and the volume fraction of the micelles. Their study finds that temperature, polymer molecular weight and sodium carbonate concentration all have a strong influence on the phase behavior of the triblock copolymers. An in-situ neutron diffraction study on decomposition of Ti2 AlN at 1500–1800 ◦ C in vacuum is described in the paper of Pang et al. Complementory depth-profiling of near surface composition and examination of the cross-sectional microstructures of decomposed Ti2 AlN, were conducted using grazing-incidence synchrotron radiation diffraction and SEM. These measurements support neutron diffraction results that show decomposition proceeding primarily via sublimation of Al from grain surfaces. In summary, this collection of papers is a sampling of the emerging body of research that exploits powerful new neutron and X-ray diffraction capabilities. The combination of small beams, high flux synchrotron radiation, new neutron techniques and advanced computer reconstruction, allows researchers to obtain unique new information about local and near surface structure at different length scales. Guest Editor Rozaliya I. Barabash a,b,∗ Guest Editor Gene E. Ice a a MST Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831-6118, USA b Materials Science and Engineering Department, University of Tennessee, Knoxville, TN 37996, USA ∗ Corresponding
author at: MST Division, Oak Ridge National Laboratory, One Bethel valley Road, Oak Ridge, TN 37831-6118, USA. Tel.: +1 865 2417230; fax: +1 865 5747659. E-mail address: [email protected] (R.I. Barabash)