Pub Date : 2020-05-20DOI: 10.5772/intechopen.92607
Y. Kohzuki
Strain-rate cycling tests associated with the ultrasonic oscillation were conducted for the purpose of investigation on the interaction between dislocation and dopant ions during plastic deformation of seven kinds of single crystals: NaCl doped with Li + , K + , Rb + , Cs + , F − , Br − or I − ions separately. Relative curves between the stress decrement ( Δ τ ) due to ultrasonic oscillatory stress and strain-rate sensitivity ( λ ) of flow stress under superposition of the oscillation are obtained by the original method (combination method of strain-rate cycling tests and application of ultrasonic oscillations) at 77 K to room temperature and have stair-like shapes for the specimens at low temperatures. The Gibbs free energy for overcoming of the dopant ion by dislocation at absolute zero is calculated from the data analyzed in terms of Δ τ vs. λ . As a result, the obtained energies are found to be varied linearly with the isotropic defect around it in the each specimen.
采用超声振荡耦合应变速率循环试验，研究了7种单晶NaCl分别掺杂Li +、K +、Rb +、Cs +、F−、Br−或I−离子时，位错与掺杂离子在塑性变形过程中的相互作用。超声振荡应力引起的应力减量(Δ τ)与振荡叠加下流变应力的应变率灵敏度(λ)之间的相对曲线由原始方法(应变率循环试验与超声振荡结合的方法)在77 K至室温下得到，低温下试样呈阶梯状。根据所分析的数据，用Δ τ vs λ计算了绝对零度下掺杂离子被位错克服的吉布斯自由能。结果发现，得到的能量随其周围各向同性缺陷在每个试样中呈线性变化。
{"title":"Study on Dislocation-Dopant Ions Interaction during Plastic Deformation by Combination Method of Strain-Rate Cycling Tests and Application of Ultrasonic Oscillations","authors":"Y. Kohzuki","doi":"10.5772/intechopen.92607","DOIUrl":"https://doi.org/10.5772/intechopen.92607","url":null,"abstract":"Strain-rate cycling tests associated with the ultrasonic oscillation were conducted for the purpose of investigation on the interaction between dislocation and dopant ions during plastic deformation of seven kinds of single crystals: NaCl doped with Li + , K + , Rb + , Cs + , F − , Br − or I − ions separately. Relative curves between the stress decrement ( Δ τ ) due to ultrasonic oscillatory stress and strain-rate sensitivity ( λ ) of flow stress under superposition of the oscillation are obtained by the original method (combination method of strain-rate cycling tests and application of ultrasonic oscillations) at 77 K to room temperature and have stair-like shapes for the specimens at low temperatures. The Gibbs free energy for overcoming of the dopant ion by dislocation at absolute zero is calculated from the data analyzed in terms of Δ τ vs. λ . As a result, the obtained energies are found to be varied linearly with the isotropic defect around it in the each specimen.","PeriodicalId":378601,"journal":{"name":"Electron Crystallography","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-05-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121314204","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-05-08DOI: 10.5772/intechopen.92212
Mohammad Jafari Eskandari, Reza Gostariani, M. A. Asadabad
Structural and analytical characterization, in the nanometer scale, has become very important for all types of materials in recent years. Transmission electron microscope (TEM) is a perfect instrument for this purpose, which is summarized in this chapter. Parameters such as particle size, grain size, lattice type, morphological information, crystallographic details, chemical composition, phase-type, and distribution can be obtained by transmission electron micrographs. Electron diffraction patterns of nanomaterials are also used to acquire quantitative information containing size, phase identification, orientation relationship and crystal defects in the lattice structure, etc. In this chapter, typical electron diffraction, high-resolution transmission and scanning transmission electron microscope imaging in materials research, especially in the study of nanoscience are presented.
{"title":"Transmission Electron Microscopy of Nanomaterials","authors":"Mohammad Jafari Eskandari, Reza Gostariani, M. A. Asadabad","doi":"10.5772/intechopen.92212","DOIUrl":"https://doi.org/10.5772/intechopen.92212","url":null,"abstract":"Structural and analytical characterization, in the nanometer scale, has become very important for all types of materials in recent years. Transmission electron microscope (TEM) is a perfect instrument for this purpose, which is summarized in this chapter. Parameters such as particle size, grain size, lattice type, morphological information, crystallographic details, chemical composition, phase-type, and distribution can be obtained by transmission electron micrographs. Electron diffraction patterns of nanomaterials are also used to acquire quantitative information containing size, phase identification, orientation relationship and crystal defects in the lattice structure, etc. In this chapter, typical electron diffraction, high-resolution transmission and scanning transmission electron microscope imaging in materials research, especially in the study of nanoscience are presented.","PeriodicalId":378601,"journal":{"name":"Electron Crystallography","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133997241","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-03-11DOI: 10.5772/intechopen.91281
T. Aizawa, T. Shiratori, T. Komatsu
Austenitic stainless steel type AISI304 sheets and plates as well as finegrained type AISI316 (FGSS316) substrates and wires were employed as a work material in the intense rolling, the piercing and the plasma nitriding. AISI304 sheet after intense rolling had textured microstructure in the rolling direction. Crystallographic state changed itself to have distorted polycrystalline state along the shearing plane by piercing, with the strain induced phase transformation. FGSS316 substrates were plasma nitrided at 623 K for 14.4 ks to have two-phase fine nanostructure with the average grain size of 100 nm as a surface layer with the thickness of 30 μm. FGSS316 wires were also plasma nitrided at the same conditions to form the nitrided surface down to the depth of 30 μm. This nitrided wire was further uniaxially loaded in tensile to attain more homogeneously nitrided surface nano-structure and to form the austenitic and martensitic fiber structure aligned in the tensile direction. Each crystallographic structure intrinsic to metals and metallic alloys was tailored to have preferable micro−/nano-structured cells by metal forming and nitrogen supersaturation. The crystallographic change by metal forming in a priori and posterior to nitriding was discussed to find out a new way for materials design.
{"title":"Micro-/Nano-Structuring in Stainless Steels by Metal Forming and Materials Processing","authors":"T. Aizawa, T. Shiratori, T. Komatsu","doi":"10.5772/intechopen.91281","DOIUrl":"https://doi.org/10.5772/intechopen.91281","url":null,"abstract":"Austenitic stainless steel type AISI304 sheets and plates as well as finegrained type AISI316 (FGSS316) substrates and wires were employed as a work material in the intense rolling, the piercing and the plasma nitriding. AISI304 sheet after intense rolling had textured microstructure in the rolling direction. Crystallographic state changed itself to have distorted polycrystalline state along the shearing plane by piercing, with the strain induced phase transformation. FGSS316 substrates were plasma nitrided at 623 K for 14.4 ks to have two-phase fine nanostructure with the average grain size of 100 nm as a surface layer with the thickness of 30 μm. FGSS316 wires were also plasma nitrided at the same conditions to form the nitrided surface down to the depth of 30 μm. This nitrided wire was further uniaxially loaded in tensile to attain more homogeneously nitrided surface nano-structure and to form the austenitic and martensitic fiber structure aligned in the tensile direction. Each crystallographic structure intrinsic to metals and metallic alloys was tailored to have preferable micro−/nano-structured cells by metal forming and nitrogen supersaturation. The crystallographic change by metal forming in a priori and posterior to nitriding was discussed to find out a new way for materials design.","PeriodicalId":378601,"journal":{"name":"Electron Crystallography","volume":"444 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-03-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115867613","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-03-03DOI: 10.5772/intechopen.91372
Devinder Singh, S. Hovmöller
Complete 3D electron diffraction can be collected by rotation electron diffraction (RED) for single-crystal powder-sized samples, i.e., <0.1 μ m, in all dimensions. Data collection takes about 1 h and data processing takes another hour. The crystal structures are solved by standard crystallographic techniques. X-ray crystallography requires crystals several micrometers big. For nanometer-sized crystals, electron diffraction and electron microscopy (EM) are the only possibilities. Two methods have been developed for collecting complete (except for a missing cone) three-dimensional (3D) electron diffraction data: the rotation electron diffraction and automated electron diffraction tomography (ADT). By collecting 1000–2000 electron diffraction patterns, a complete 3D data set is obtained. The geometry in RED is analogous to the rotation method in X-ray crystallography; the sample is rotated continuously along one rotation axis. In recent years, large number of crystal structures has been solved by RED. These include the most complex zeolites ever solved and quasicrystal approximants, such as the pseudo-decagonal approximants PD2 and PD1 in Al-Co-Ni. In this chapter, the results of our recent studies on the structure analysis of complex pseudo-decagonal (PD) quasicrystal approximants PD2 ( a = 23.2, b = 32.3, c = 4.1 Å) and PD1 ( a = 37.3, b = 38.8, c = 4.1 Å) by RED have been discussed. These are known to be the most complicated approximant structures ever solved to atomic resolution by electron crystallography. PD2 and PD1 are built of characteristic 2 nm wheel clusters with fivefold rotational symmetry, which agrees with other approximants in the PD series as well as with the results from high-resolution electron microscopy images.
旋转电子衍射(RED)可以收集到单晶粉末尺寸样品(即<0.1 μ m)在所有维度上完整的三维电子衍射。数据采集耗时约1小时，数据处理耗时约1小时。晶体结构用标准晶体学技术求解。x射线晶体学需要几微米大的晶体。对于纳米尺寸的晶体，电子衍射和电子显微镜(EM)是唯一的可能性。为了收集完整的三维电子衍射数据(除了缺少一个锥体)，已经开发了两种方法:旋转电子衍射和自动电子衍射层析成像(ADT)。通过采集1000 ~ 2000张电子衍射图，获得了完整的三维数据集。RED的几何结构类似于x射线晶体学中的旋转方法;样品沿一个旋转轴连续旋转。近年来，大量的晶体结构已被红外光谱解译。这些包括最复杂的沸石和准晶近似物，如Al-Co-Ni中的伪十方近似物PD2和PD1。在这一章中，讨论了我们最近用RED对复杂伪十角体(PD)准晶近似物PD2 (a = 23.2, b = 32.3, c = 4.1 Å)和PD1 (a = 37.3, b = 38.8, c = 4.1 Å)的结构分析的研究结果。这些被认为是电子晶体学在原子分辨率上解决的最复杂的近似结构。PD2和PD1是由具有五重旋转对称的2 nm特征轮簇构成的，这与PD系列中的其他近似以及高分辨率电子显微镜图像的结果一致。
{"title":"Structure Analysis of Quasicrystal Approximants by Rotation Electron Diffraction (RED)","authors":"Devinder Singh, S. Hovmöller","doi":"10.5772/intechopen.91372","DOIUrl":"https://doi.org/10.5772/intechopen.91372","url":null,"abstract":"Complete 3D electron diffraction can be collected by rotation electron diffraction (RED) for single-crystal powder-sized samples, i.e., <0.1 μ m, in all dimensions. Data collection takes about 1 h and data processing takes another hour. The crystal structures are solved by standard crystallographic techniques. X-ray crystallography requires crystals several micrometers big. For nanometer-sized crystals, electron diffraction and electron microscopy (EM) are the only possibilities. Two methods have been developed for collecting complete (except for a missing cone) three-dimensional (3D) electron diffraction data: the rotation electron diffraction and automated electron diffraction tomography (ADT). By collecting 1000–2000 electron diffraction patterns, a complete 3D data set is obtained. The geometry in RED is analogous to the rotation method in X-ray crystallography; the sample is rotated continuously along one rotation axis. In recent years, large number of crystal structures has been solved by RED. These include the most complex zeolites ever solved and quasicrystal approximants, such as the pseudo-decagonal approximants PD2 and PD1 in Al-Co-Ni. In this chapter, the results of our recent studies on the structure analysis of complex pseudo-decagonal (PD) quasicrystal approximants PD2 ( a = 23.2, b = 32.3, c = 4.1 Å) and PD1 ( a = 37.3, b = 38.8, c = 4.1 Å) by RED have been discussed. These are known to be the most complicated approximant structures ever solved to atomic resolution by electron crystallography. PD2 and PD1 are built of characteristic 2 nm wheel clusters with fivefold rotational symmetry, which agrees with other approximants in the PD series as well as with the results from high-resolution electron microscopy images.","PeriodicalId":378601,"journal":{"name":"Electron Crystallography","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129482331","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-11-26DOI: 10.5772/INTECHOPEN.90237
F. Fang, S. Paduroiu, Dugan Hammock, K. Irwin
In quasicrystals, any given local patch—called an emperor—forces at all distances the existence of accompanying tiles—called the empire—revealing thus their inherent nonlocality. In this chapter, we review and compare the methods currently used for generating the empires, with a focus on the cut-and-project method, which can be generalized to calculate empires for any quasicrystals that are projections of cubic lattices. Projections of non-cubic lattices are more restrictive and some modifications to the cut-and-project method must be made in order to correctly compute the tilings and their empires. Interactions between empires have been modeled in a game-of-life approach governed by nonlocal rules and will be discussed in 2D and 3D quasicrystals. These nonlocal properties and the consequent dynamical evolution have many applications in quasicrystals research, and we will explore the connections with current material science experimental research.
{"title":"Empires: The Nonlocal Properties of Quasicrystals","authors":"F. Fang, S. Paduroiu, Dugan Hammock, K. Irwin","doi":"10.5772/INTECHOPEN.90237","DOIUrl":"https://doi.org/10.5772/INTECHOPEN.90237","url":null,"abstract":"In quasicrystals, any given local patch—called an emperor—forces at all distances the existence of accompanying tiles—called the empire—revealing thus their inherent nonlocality. In this chapter, we review and compare the methods currently used for generating the empires, with a focus on the cut-and-project method, which can be generalized to calculate empires for any quasicrystals that are projections of cubic lattices. Projections of non-cubic lattices are more restrictive and some modifications to the cut-and-project method must be made in order to correctly compute the tilings and their empires. Interactions between empires have been modeled in a game-of-life approach governed by nonlocal rules and will be discussed in 2D and 3D quasicrystals. These nonlocal properties and the consequent dynamical evolution have many applications in quasicrystals research, and we will explore the connections with current material science experimental research.","PeriodicalId":378601,"journal":{"name":"Electron Crystallography","volume":"55 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-11-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120897243","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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