Electrodeposited Nanocrystalline Ni-Fe with Banded Structure

2012 ◽  
Vol 706-709 ◽  
pp. 1618-1623 ◽  
Author(s):  
Uta Klement ◽  
Mehrdad Shahabi-Navid ◽  
Glenn D. Hibbard
Keyword(s):  
Grain Growth ◽  
Electron Backscatter Diffraction ◽  
Growth Direction ◽  
Phase Changes ◽  
Growth Behaviour ◽  
General Behaviour ◽  
Banded Structure ◽  
Ebsd Technique ◽  
Backscatter Diffraction

The microstructure of a Ni–18 wt.% Fe electrodeposits having a banded structure is described in detail. The aim is to investigate the influence of the banded structure on grain growth behaviour and texture and to elucidate if there are other mechanisms operative in the stabilization of nanocrystalline electrodeposits. Spectroscopy techniques have been used to characterize the variations in alloy/impurity concentration perpendicular to the growth direction. The influence of these chemical variations on the microstructural evolution has been monitored by in-situ annealing treatments in the TEM. Local texture of the annealed material has been determined by use of the electron backscatter diffraction (EBSD) technique. SEM and TEM investigations have shown that the banded structure is not related to phase changes and that grain growth is not affected by the banded structure, i.e. there is no preferred growth along bands. The first grown grains have <100>, <112> and <111> orientations with the growth direction and upon further grain growth a <111> fibre texture with respect to the growth direction of the electrodeposits is formed. The banded structure seems not to affect the general behaviour of nanocrystalline electrodeposits.

Effect of Annealing on Microstructural Development and Grain Orientation in Electrodeposited Ni

2010 ◽  
Vol 160 ◽  
pp. 235-240 ◽  
Author(s):  
Uta Klement ◽  
L. Hollang ◽  
S.R. Dey ◽  
M. Battabyal ◽  
O.V. Mishin ◽  
...  
Keyword(s):  
Grain Growth ◽  
Cross Sections ◽  
Electron Backscatter Diffraction ◽  
Microstructural Development ◽  
Growth Behaviour ◽  
Coalescence Model ◽  
Transmission Electron ◽  
Columnar Grains ◽  
Backscatter Diffraction

Thick (up to 5 mm) Ni electrodeposits were produced by the pulsed electrodeposition (PED) technique. The PED-Ni was investigated in planar and cross-sections using high resolution scanning electron microscopy. Grain size and local texture were studied by electron backscatter diffraction. Thermal stability and grain growth behaviour were investigated using in-situ annealing in the transmission electron microscope. It is observed that columnar grains are present in the material and that the orientation of grains is not uniform. Textures and in-situ annealing behaviour are compared to previous data on nanocrystalline PED-Ni and Ni-Fe, where a subgrain coalescence model adopted from recrystallization is used to describe the occurrence of abnormal grain growth upon annealing and where twinning was found to be responsible for the texture development.

Grain Growth in Al: First Results from a Combined Study of Bulk and In-Situ Experiments Using a Columnar Structured Al Foil

2004 ◽  
Vol 467-470 ◽  
pp. 935-940 ◽  
Author(s):  
Sandra Piazolo ◽  
Vera G. Sursaeva ◽  
David J. Prior
Keyword(s):  
Grain Boundary ◽  
Grain Growth ◽  
Electron Backscatter Diffraction ◽  
Boundary Energy ◽  
Complete Replacement ◽  
Von Neumann ◽  
In Situ Experiments ◽  
First Results ◽  
Backscatter Diffraction

First results from grain growth experiments in a columnar structured Al foil show several interesting features: (a) the grain size distribution remains heterogeneous even after up to 300 min. annealing and (b) the Von Neumann-Mullins relation is not always satisfied. To clarify the underlying reasons for these features, in-situ heating experiments within a Scanning Electron Microscope (SEM) were combined with detailed Electron Backscatter Diffraction (EBSD) analysis. These show that the movement of boundaries can be strongly heterogeneous. For example, the complete replacement of one grain by a neighbouring grain without significant change of the surrounding grain boundary topology is frequently seen. Experiments show that grain boundary energy and/or mobility are anisotropic both with respect to misorientation and orientation of grain boundary plane. Low energy and/or mobility boundaries are commonly low angle boundaries, twin boundaries and boundaries that form traces to a low index plane of at least one of the adjacent grains. As a consequence the Von Neumann-Mullins relation is not always satisfied.

Thermomechanical behavior and microstructural evolution in tantalum thin films

2004 ◽  
Vol 854 ◽  
Author(s):  
Robert Knepper ◽  
Katherine Jackson ◽  
Blake Stevens ◽  
Shefford P. Baker
Keyword(s):  
Phase Transformation ◽  
Grain Growth ◽  
Electron Backscatter Diffraction ◽  
High Vacuum ◽  
Ultra High Vacuum ◽  
Tensile Direction ◽  
Grain Sizes ◽  
Curvature Measurement ◽  
Backscatter Diffraction

ABSTRACTTa films were prepared in the metastable β phase using an ultra-high vacuum sputter deposition system. The stresses that arose during thermal cycles to 750°C were measured using an in situ substrate curvature measurement system, allowing oxygen content in the films to be minimized. A phase transformation from β to the stable α phase takes place in conjunction with distinct “jumps” in stress in the tensile direction during heating at approximately 400°C and 650°C. X-ray and electron backscatter diffraction (EBSD) analyses were used to determine grain sizes, along with crystal phase and orientation information. These results indicate a significant amount of grain growth accompanying the phase transformation. It is found that the measured total stress change is in reasonable agreement with that predicted by the combination of grain growth, crystal densification associated with the phase transformation, and stress relaxation.

Investigation of the Deformation Twins on the Bending Cross Section of TA2 Titanium Sheet

2020 ◽  
Vol 837 ◽  
pp. 41-45
Author(s):  
Shuai Sun ◽  
Kai Hua Liu
Keyword(s):  
Electron Backscatter Diffraction ◽  
Testing Machine ◽  
Pure Titanium ◽  
Titanium Sheet ◽  
Bending Tests ◽  
Three Point Bending ◽  
Deformation Twins ◽  
Ebsd Technique ◽  
Backscatter Diffraction ◽  
Deformation Area

In order to determine the evolution features of deformation twins for TA2 commercial pure titanium (cp-TA2), the TA2 samples were bent under different bending angles in three-point bending tests via a universal testing machine. The electron backscatter diffraction (EBSD) technique was applied to identify the grain boundaries (GBs) and twin boundaries (TBs) in the bending areas. The results reveal that the type of deformation area would effect the evolution of different deformation twins. It is inferred that the state of stress would promote the multiplication of the same type of deformation twins.

scholarly journals On the Use of EBSD and Microhardness to Study the Microstructure Properties of Tungsten Samples Prepared by Selective Laser Melting

Materials ◽  
2021 ◽  
Vol 14 (5) ◽  
pp. 1215
Author(s):  
Mirza Atif Abbas ◽  
Yan Anru ◽  
Zhi Yong Wang
Keyword(s):  
Selective Laser Melting ◽  
Electron Backscatter Diffraction ◽  
Fusion Reactors ◽  
Laser Melting ◽  
Kikuchi Pattern ◽  
Plasma Facing Components ◽  
Electron Backscatter ◽  
Ebsd Technique ◽  
Temperature Exposure ◽  
Backscatter Diffraction

Additively manufactured tungsten and its alloys have been widely used for plasma facing components (PFCs) in future nuclear fusion reactors. Under the fusion process, PFCs experience a high-temperature exposure, which will ultimately affect the microstructural features, keeping in mind the importance of microstructures. In this study, microhardness and electron backscatter diffraction (EBSD) techniques were used to study the specimens. Vickers hardness method was used to study tungsten under different parameters. EBSD technique was used to study the microstructure and Kikuchi pattern of samples under different orientations. We mainly focused on selective laser melting (SLM) parameters and the effects of these parameters on the results of different techniques used to study the behavior of samples.

Texture and Microstructure Evolution in Friction Stir Welded Cu-Al Sheets Characterized by EBSD

2011 ◽  
Vol 702-703 ◽  
pp. 574-577 ◽  
Author(s):  
Daniel Goran ◽  
G. Ji ◽  
M. N. Avettand-Fènoël ◽  
R. Taillard
Keyword(s):  
Microstructure Evolution ◽  
Electron Backscatter Diffraction ◽  
Texture Evolution ◽  
Weld Interface ◽  
Friction Stir ◽  
Electron Backscatter ◽  
Ebsd Technique ◽  
Backscatter Diffraction

Texture and microstructure of FSW joined Al and Cu sheets were investigated by means of electron backscatter diffraction (EBSD) technique. The analysis has revealed a strong texture evolution on both sides of the weld interface as well as a very complex microstructure. Grains were found to be fully recrystallized on both sides of the weld and with different average diameters at different specific zones of the weld.

scholarly journals Initiation and short crack growth behaviour of environmentally induced cracks in AA5083 H131 investigated across time and length scales

2019 ◽  
Vol 37 (5) ◽  
pp. 469-481 ◽  
Author(s):  
Visweswara C. Gudla ◽  
Alistair Garner ◽  
Malte Storm ◽  
Parmesh Gajjar ◽  
James Carr ◽  
...  
Keyword(s):  
Electron Backscatter Diffraction ◽  
Three Dimensional ◽  
High Strength ◽  
Time Lapse ◽  
Growth Behaviour ◽  
Spectroscopy Analysis ◽  
Crack Growth Behaviour ◽  
Rate Testing ◽  
X Ray Computed ◽  
Backscatter Diffraction

AbstractEnvironmentally induced cracking (EIC) in a sensitized high-strength AA5083 H131 alloy has been investigated using time-lapse synchrotron X-ray computed tomography combined with post-mortem correlative characterization. Small corrosion features deliberately introduced in a pre-exposure step were found to be the site of initiation for over 95% of the 44 EIC cracks that developed under slow strain rate testing. Detailed analysis using three-dimensional electron backscatter diffraction and energy-dispersive spectroscopy analysis of a single crack confirmed the intergranular nature of the cracks from the start and that the pre-exposure corrosion was associated with an α-AlFeMnSi particle cluster. It also appears that several cracks may have initiated at this site, which later coalesced to form the 300-μm-long crack that ultimately developed. Of further note is the fact that initiation of the EIC cracks across the sample started below the yield strength and continued beyond the ultimate tensile strength. The most rapid crack propagation occurred during sample extension following a period of fixed displacement.

Sign in / Sign up

Export Citation Format

Share Document