scholarly journals Continuous Electron Beam Post-Treatment of EBF3-Fabricated Ti–6Al–4V Parts

Metals ◽  
2019 ◽  
Vol 9 (6) ◽  
pp. 699 ◽  
Author(s):  
Alexey Panin ◽  
Marina Kazachenok ◽  
Olga Perevalova ◽  
Sergey Martynov ◽  
Alexandra Panina ◽  
...  
Keyword(s):  
Surface Layer ◽  
Electron Beam ◽  
Surface Finish ◽  
Martensitic Transformations ◽  
Post Treatment ◽  
X Ray Diffraction ◽  
Orthorhombic Martensite ◽  
Α Phase ◽  
Transmission Electron ◽  
Outermost Surface

In the present study, the methods of optical, scanning electron, and transmission electron microscopy as well as X-ray diffraction analysis gained insights into the mechanisms of surface finish and microstructure formation of Ti–6Al–4V parts during an EBF3-process. It was found that the slip band propagation within the outermost surface layer provided dissipation of the stored strain energy associated with martensitic transformations. The latter caused the lath fragmentation as well as precipitation of nanosized β grains and an orthorhombic martensite α″ phase at the secondary α lath boundaries of as-built Ti–6Al–4V parts. The effect of continuous electron beam post-treatment on the surface finish, microstructure, and mechanical properties of EBF3-fabricated Ti–6Al–4V parts was revealed. The brittle outermost surface layer of the EBF3-fabricated samples was melted upon the treatment, resulting in the formation of equiaxial prior β grains of 20 to 30 μm in size with the fragmented acicular α′ phase. Electron-beam irradiation induced transformations within the 70 μm thick molten surface layer and 500 μm thick heat affected zone significantly increased the Vickers microhardness and tensile strength of the EBF3-fabricated Ti–6Al–4V samples.

scholarly journals Experimental Study of the Influence of Shot Peening on the Microstructure and Properties of Surface Layer of a TC21 Titanium Alloy

2017 ◽  
Vol 1 (1) ◽  
pp. 17-23
Author(s):  
Y. Song ◽  
Z. Zhao ◽  
F. Lu
Keyword(s):  
Titanium Alloy ◽  
Surface Layer ◽  
Shot Peening ◽  
Original Material ◽  
X Ray Diffraction ◽  
Nano Indentation ◽  
Microstructure And Properties ◽  
Α Phase ◽  
Transmission Electron ◽  
Electron Back Scattered Diffraction

The effects of shot peening on microstructure and properties of surface layer of a TC21 titanium alloy have been studied by transmission electron microscopy, electron back-scattered diffraction, X-ray diffraction and Nano-indentation. The results indicated that an elastic-plastic strengthening layer was formed on the surface of the TC21 alloy after the shot peening. During the deformation processing, the activated slip systems were found to be in <a>, <c> and <a/c> planes with high-density dislocations formed as networks in α phase. After the shot peening, the residual stress was found in the strengthening layer, which decreased from the surface to the interior, and the thickness of the surface layer was measured about 370 μm. The hardness by nano-indentation measurement increased two times as compared with the original material. After the shot peening, the fraction of the low-angle boundaries between 0-10º was estimated as 59.3% at the depth of 100 μm from surface. This surface layer microstructure improved resistance of deformation of the TC21 alloy, and therefore increased its fatigue strength.

Relationship between the Textures and the Elastic Moduli of Electron Beam Welded Joint in Ti-6Al-4V Titanium Alloy

2014 ◽  
Vol 936 ◽  
pp. 1910-1917
Author(s):  
Xing Zhi Li ◽  
Shu Bing Hu
Keyword(s):  
Titanium Alloy ◽  
Electron Beam ◽  
Elastic Modulus ◽  
Elastic Moduli ◽  
Electron Beam Welding ◽  
Base Material ◽  
X Ray Diffraction ◽  
Electron Backscattered Diffraction ◽  
Α Phase ◽  
Transmission Electron

The microstructure, texture and elastic modulus of electron beam welding joint in Ti-6Al-4V titanium alloy were investigated by transmission electron microscopy, X-ray diffraction, electron back scattered diffraction and nanoindentation techniques. The α phase was in the majority, and a {0001} <-2110> texture of α phase was observed in the base material. A very weak {11-23} <-1-122> texture of α phase was in the fuse zone. Most of the α grain boundaries in the fuse zone were high-angle boundaries by electron backscattered diffraction, and it also confirmed that the orientations of α phase had a nearly random distribution in the fuse zone. The maximum average elastic modulus value measured by the nanoindentation techniques was in the base material due to the effect of the {0001} <-2110> texture. The average elastic moduli of three different zones in the joint were 134.8±3.5Gpa, 125.5±5.8Gpa and 123.0±4.7Gpa, respectively.

Al Si Oxide Coating as Ttritium Penetration Barrier on 316L Stainless Steel Prepared by a Combined Process

2008 ◽  
Vol 59 ◽  
pp. 76-81
Author(s):  
Hong Bing Liu ◽  
Jie Tao ◽  
Jiang Xu ◽  
Zhao Feng Chen ◽  
Xian Jun Sun
Keyword(s):  
Photoelectron Spectroscopy ◽  
Hydrogen Permeability ◽  
Oxide Coating ◽  
Favorable Effect ◽  
X Ray Diffraction ◽  
Combined Process ◽  
X Ray ◽  
Transmission Electron ◽  
Outermost Surface ◽  
Glow Plasma

Based on the favorable effect of the elements Al and Si on the improvement in reducing hydrogen permeability, a new combined process of simultaneous aluminizing and siliconizing, followed by oxidizing treatments using double glow plasma technology on 316L substrate was developed in this work. Microstructure and phase structure of as- prepared coating was examined by scanning electronic microscopy (SEM), X-ray diffraction analysis (XRD), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS), respectively. The results showed that the simultaneous aluminizing and siliconizing coating consisted of an outer aluminide layer (dissolved Si) and a diffusion zone. After a combined process, a continuous and compact Al2O3-rich coating was formed at the outermost surface. SiO2 was also detectable in the oxide coating.

Cobalt and Titanium Metallization of SiGeC for Shallow Contacts

1996 ◽  
Vol 427 ◽  
Author(s):  
A. E Bair ◽  
T. L. Alford ◽  
Z. Atzmon ◽  
S. D. Marcus ◽  
D. C. Doller ◽  
...  
Keyword(s):  
Surface Layer ◽  
Electron Beam ◽  
Rutherford Backscattering Spectrometry ◽  
X Ray Diffraction ◽  
X Ray ◽  
Analysis Techniques ◽  
Annealing Conditions ◽  
Contact Metallization ◽  
Glancing Angle ◽  
Device Structures

AbstractShallow contact metallization of SiGeC was studied in anticipation of this alloys use in low power applications. It has been shown that in the solid state reaction of Co on (100) Si, that Co is the moving species with proper annealing conditions. This prevents the formation of Kirkendal voiding in certain device structures. This work studies the Co and Ti metallization of SiGeC. A bilayer of 44 nm of Co on 7 nm of Ti, were electron beam evaporated onto epitaxially grown Si0.77Ge0.21C0.02. The samples were rapid thermal processed at 600 and 900 °C for up to two minutes in a nitrogen ambient. The analysis techniques used were Rutherford backscattering spectrometry which included the used of the 4.27 MeV 12C(α,α) 12C resonance reaction, glancing angle x-ray diffraction, During annealing at all temperatures, Co diffused through the Ti layer and formed CoSi. This phase was confirmed by x-ray diffraction. The Co displaced the Ti to the surface. At 600 °C, Ge diffused to the surface layer, while at 900 °C it was rejected back into the original SiGeC. The sample annealed at 600 °C was subsequently annealed at 900 °C. The Ge in the surface layer was rejected from the surface layer, diffused across the CoSi and back into the SiGeC.

scholarly journals Enhancing the Mechanical Properties of Cross-Linked Rubber-Toughened Nanocomposites via Electron Beam Irradiation

2011 ◽  
Vol 2011 ◽  
pp. 1-8 ◽  
Author(s):  
N. A. Jamal ◽  
H. Anuar ◽  
A. R. Shamsul Bahri
Keyword(s):  
Mechanical Properties ◽  
Electron Beam ◽  
Xrd Analysis ◽  
Mechanical Tests ◽  
X Ray Diffraction ◽  
Morphological Examination ◽  
Crosslinking Degree ◽  
Transmission Electron ◽  
Rubber Toughened ◽  
Organophilic Montmorillonite

Improving the mechanical properties of a pristine system is the main target of developing nanocomposites. The nanocomposites systems were first prepared via intercalation technique with different organophilic montmorillonite (OMMT) loading. Two types of cross-linking techniques were applied, namely, as maleic anhydride polyethylene (MAPE) and electron beam (EB) irradiated system. The effectiveness of these systems was then compared with the control one and analyzed based on the mechanical tests and morphological examination. The mechanical tests revealed that control, MAPE, and EB irradiated systems had attained the optimum mechanical properties at 4 vol% OMMT content. EB irradiated unit of a dose of 100 kGy showed excellent mechanical properties with higher crosslinking degree which were proved by gel content analysis. X-ray diffraction (XRD) analysis confirmed the existence of delamination structure with MAPE and EB irradiation techniques based on the disappearance of characteristic peak. The degree of delamination was further investigated by transmission electron microscope (TEM).

The distribution of condensed defect structures formed in annealed boron-implanted silicon

1969 ◽  
Vol 311 (1504) ◽  
pp. 75-78 ◽  
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Surface Layer ◽  
Electron Beam ◽  
Electron Microscope ◽  
Turbulent Jet ◽  
Doping Profile ◽  
Defect Structures ◽  
Transmission Electron ◽  
Boron Ions

Silicon has been implanted with between 10 14 and 10 16 boron ions/cm 2 at energies of 25, 50, 75 and 100 keV; it has also been annealed at temperatures of between 873 and 1073 °K when the implanted boron ions occupy substitutional sites and form a ‘doped’ surface layer in which the doping profile can be accurately controlled, a desirable property in the manufacture of solid state circuits and devices (Large & Bicknell 1967). The implanted layers have been examined by both electron microscopy and electron diffraction before, during and after annealing to study the changes in crystal structures involved. For transmission electron microscope studies the silicon must be thinned to provide areas less than 1 p m in thickness, otherwise the electron beam is entirely absorbed within the specimen. It has been found that a modified form of jet etching using a turbulent jet enables large areas suitable for transmission electron microscopy to be easily produced from all types of specimens, both annealed and unannealed. Although specimens have been prepared and implanted with boron ions of different energies and doses the results discussed, which are typical of the range covered, are those obtained from silicon implanted with single energy 50 keV boron ions with a dose of 2 x 10 15 ions/cm 2 .

Characterization and Electrical Conductivity of Electron Beam Irradiated Metal Phthalocyanine Complexes

2017 ◽  
Vol 14 (1) ◽  
pp. 1-7
Author(s):  
Ashok R Lamani H S Jayanna
Keyword(s):  
Electrical Conductivity ◽  
Electron Beam ◽  
Localized States ◽  
Thermal Excitation ◽  
X Ray Diffraction ◽  
Β Phase ◽  
Α Phase ◽  
Semiconductor Behavior ◽  
Lower Temperature ◽  
Straight Lines

Variation of DC electrical conductivity with temperature from 273-473 K of electron beam irradiated Tetra-nitro zinc, and Cu-Pcs,   were carried out. It   shows semiconductor behavior and resistivity varies from 0.043×10 5 Ω -cm to 64.61×10 5 Ω -cm for all complexes. Variation of conductivity with temperature shows two straight lines of different slopes the first line (LT), resembles the α– phase, (Ea 1 ) = 0.226 eV while the second line at 362 K resembles the β - phase (Ea 2 ) = 0.460 eV (for Cu- Pcs). The β -phase shows higher activation energy than the α -phase, and the X-ray diffraction studies reveal that the crystals are monoclinic. The conductivity is explained on the basis of Davis and Mott model. The conduction mechanism at lower temperature is explained in terms of hoping through a band of localized states and at higher temperatures in terms of thermal excitation of carriers to the band edge.

Understanding Precursor Phenomena for the R-Phase Transformation in Ti-Ni-Based Alloys

MRS Bulletin ◽  
2002 ◽  
Vol 27 (2) ◽  
pp. 121-127 ◽  
Author(s):  
Daisuke Shindo ◽  
Yasukazu Murakami ◽  
Takuya Ohba
Keyword(s):  
Phase Transformation ◽  
Diffuse Scattering ◽  
Parent Phase ◽  
Martensitic Transformations ◽  
X Ray Diffraction ◽  
X Ray ◽  
Atomic Displacements ◽  
Transmission Electron ◽  
Critical Issues ◽  
Structural Modulation

AbstractPrecursor phenomena are critical issues for martensitic transformations. In this article, we show recent progress in understanding precursor phenomena to the R-phase transformation, which is important for both fundamentals and applications. Structural modulation in the parent phase was intensively studied by means of detailed analyses of the weak diffuse scattering of electrons with the aid of recently developed energy-filtered transmission electron microscopy coupled with x-ray diffraction. A peculiar domain-like structure, which originates from static transverse atomic displacements in the parent phase, was discovered by virtue of these advanced methods. The characteristics of this structure (e.g., size, shape, and temperature-dependence), as well as its role in the subsequent R-phase transformation, are discussed.

Hardening of the Surface Layer of Silumin by Electron Beam

2013 ◽  
Vol 872 ◽  
pp. 162-166 ◽  
Author(s):  
Yurii F. Ivanov ◽  
Elizaveta A. Petrikova ◽  
Nikolay N. Cherenda ◽  
Anton D. Teresov
Keyword(s):  
Surface Layer ◽  
Electron Beam ◽  
Bending Strength ◽  
Nanocrystalline Structure ◽  
Electron Beam Treatment ◽  
Plastic Limit ◽  
X Ray Diffraction ◽  
X Ray ◽  
The Core ◽  
Ultimate Bending Strength

In the present work has been carried out the treatment of silumin by high-intensity electron beam with different density of the input energy. The structure and phase composition of surface layer have been studied by the methods of X-ray diffraction and electron microscopy both scanning and diffraction transmission. The mechanisms are responsible for improvement of properties of modified material have been revealed. It has been shown that electron beam treatment of silumin is accompanied by the formation of multilayer submicro-and nanocrystalline structure and result in increasing the microhardness of the surface layer (towards the core) is ~ 3.5 times, the Young's modulus in a ~ 1.4 times, the ultimate bending strength (in ~ 1.2 times) and tensile strength (in ~ 1.4 times), the bending plastic limit (in ~ 1.2 times) and tensile (in ~ 1.8 times).

Microstructural Evaluation of Boron Free and Boron Containing Heat-Treated Ti-35Nb-7.2Zr-5.7Ta Alloy

2012 ◽  
Vol 18 (2) ◽  
pp. 295-303 ◽  
Author(s):  
Pallab Majumdar
Keyword(s):  
X Ray Diffraction ◽  
Second Stage ◽  
Β Phase ◽  
Solution Treated ◽  
Α Phase ◽  
Treatment Conditions ◽  
Transmission Electron ◽  
Heat Treated ◽  
Microstructural Evaluation ◽  
Diffraction Patterns

AbstractThe microstructure of Ti-35Nb-7.2Zr-5.7Ta (TNZT) and Ti-35Nb-7.2Zr-5.7Ta-0.5B (TNZTB) alloys under different heat treatment conditions has been analyzed. The solution-treated and water-quenched TNZT sample consists mainly of β phase with a very small amount of fine athermal ω precipitate. Precipitation of α can be observed when solution-treated samples are directly aged at 580°C for 8 h. The microstructure of the samples subjected to single-stage aging at 300°C or 400°C consists of ω precipitates in equiaxed β grains. Second stage aging at 580°C for 8 h after first stage of aging at 300°C or 400°C results in the replacement of ω precipitates by secondary α. In all of these samples, the amount of ω or α phase was very small, and therefore they could not be detected by X-ray diffraction studies. However, analysis of selected area diffraction patterns obtained from transmission electron microscopy studies confirms their presence. The addition of boron leads to the formation of dispersed precipitates of TiB in the β matrix of the TNZT alloy and also refines the β grains in the microstructure. However, other microstructural features of the TNZTB alloy are similar to those of the TNZT alloy.

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