Advanced Fe-Cr Alloys Studied by Pulsed Low Energy Positron System Before and After Helium Ions Implantation

Author(s):  
Stanislav Sojak ◽  
Vladimi´r Krsˇjak ◽  
Werner Egger

Positron annihilation spectroscopy (PAS) is a non-destructive technique which provides information about microstructural damage of structural materials. In this paper, the Pulsed Low Energy Positron System (PLEPS) at the research reactor FRM-II at TU Munich was used to study depth profiling of binary Fe-Cr alloys. Fe-Cr model alloys with different chromium content were investigated in the as-received state as well as after helium ion implantation (dose up to 6.24×1017 ions/cm−2). Measured results show changes in the size of defects after implantation and also in non-implanted specimens depending on the Cr content.

2017 ◽  
Vol 68 (7) ◽  
pp. 62-65
Author(s):  
Jana Simeg Veternikova ◽  
Martin Fides ◽  
Jarmila Degmova ◽  
Stanislav Sojak ◽  
Martin Petriska ◽  
...  

AbstractThree oxide dispersion strengthened (ODS) steels with different chromium content (MA 956, MA 957 and ODM 751) were studied as candidate materials for new nuclear reactors in term of their radiation stability. The radiation damage was experimentally simulated by helium ion implantation with energy of ions up to 500 keV. The study was focused on surface and sub-surface structural change due to the ion implantation observed by mostly non-destructive techniques: positron annihilation lifetime spectroscopy and nanoindentation. The applied techniques demonstrated the best radiation stability of the steel ODM 751. Blistering effect occurred due to high implantation dose (mostly in MA 956) was studied in details.


2010 ◽  
Vol 638-642 ◽  
pp. 1384-1389 ◽  
Author(s):  
Sven Neve ◽  
Kurt Stiebing ◽  
Lothar P.H. Schmidt ◽  
Hans Eberhard Zschau ◽  
Patrick J. Masset ◽  
...  

Using the halogen effect TiAl-alloys can be protected against high-temperature oxidation. Two different fluorination methods were applied to turbine blades. The mass increase due to oxidation can be drastically reduced compared to untreated specimen. A new vacuum chamber for ion beam analysis was developed to analyze the real parts. Using PIGE-technique the F-content as a function of depth before and after oxidation was detected. Thickness and composition of the oxide scale were measured by RBS. Both ion beam methods were non destructive and thus enabled for the first time quality assurance of the halogen treatment on real components.


2015 ◽  
Vol 30 (5) ◽  
pp. 1086-1099 ◽  
Author(s):  
Yves Kayser ◽  
Philipp Hönicke ◽  
Dariusz Banaś ◽  
Jean-Claude Dousse ◽  
Joanna Hoszowska ◽  
...  

Grazing XRF measurements allow for a non-destructive investigation of the depth distribution of ion implantations.


Author(s):  
Amal Ben Hadj Mabrouk ◽  
Christophe Licitra ◽  
Antoine Chateauminois ◽  
Marc Veillerot

1995 ◽  
Vol 391 ◽  
Author(s):  
W.F. Mcarthur ◽  
K.M. Ring ◽  
K.L. Kavanagh

AbstractThe feasibility of Si-implanted TiN as a diffusion barrier between Cu and Si was investigated. Barrier effectiveness was evaluated via reverse leakage current of Cu/TixSiyNz/Si diodes as a function of post-deposition annealing temperature and time, and was found to depend heavily on the film composition and microstructure. TiN implanted with Si28, l0keV, 5xl016ions/cm2 formed an amorphous ternary TixSiyNz layer whose performance as a barrier to Cu diffusion exceeded that of unimplanted, polycrystalline TiN. Results from current-voltage, transmission electron microscopy (TEM), and Auger depth profiling measurements will be presented. The relationship between Si-implantation dose, TixSiyNz structure and reverse leakage current of Cu/TixSiyNz/Si diodes will be discussed, along with implications as to the suitability of these structures in Cu metallization.


2004 ◽  
Vol 231-232 ◽  
pp. 645-648 ◽  
Author(s):  
Sarah Fearn ◽  
Richard Chater ◽  
David McPhail
Keyword(s):  

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Y. Tong ◽  
G. R. Berdiyorov ◽  
A. Sinopoli ◽  
M. E. Madjet ◽  
V. A. Esaulov ◽  
...  

AbstractThe stability of the molecular self-assembled monolayers (SAMs) is of vital importance to the performance of the molecular electronics and their integration to the future electronics devices. Here we study the effect of electron irradiation-induced cross-linking on the stability of self-assembled monolayer of aromatic 5,5′-bis(mercaptomethyl)-2,2′-bipyridine [BPD; HS-CH2-(C5H3N)2-CH2-SH] on Au (111) single crystal surface. As a refence, we also study the properties of SAMs of electron saturated 1-dodecanethiol [C12; CH3-(CH2)11-SH] molecules. The stability of the considered SAMs before and after electron-irradiation is studied using low energy Ar+ cluster depth profiling monitored by recording the X-ray photoelectron spectroscopy (XPS) core level spectra and the UV-photoelectron spectroscopy (UPS) in the valance band range. The results indicate a stronger mechanical stability of BPD SAMs than the C12 SAMs. The stability of BPD SAMs enhances further after electron irradiation due to intermolecular cross-linking, whereas the electron irradiation results in deterioration of C12 molecules due to the saturated nature of the molecules. The depth profiling time of the cross-linked BPD SAM is more than 4 and 8 times longer than the profiling time obtained for pristine and BPD and C12 SAMs, respectively. The UPS results are supported by density functional theory calculations, which show qualitative agreement with the experiment and enable us to interpret the features in the XPS spectra during the etching process for structural characterization. The obtained results offer helpful options to estimate the structural stability of SAMs which is a key factor for the fabrication of molecular devices.


Sign in / Sign up

Export Citation Format

Share Document