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1.
Recently, interest in steel alloyed with∼1% Al increased. These materials are expected to show a higher resistance against
oxidation at high temperatures which will improve their performance when used as high-speed-steels. Furthermore, efforts have
been made to combine the advantages of Al-steels with those of powder-metallurgic methods like hotisostatic-pressing (hip).
This should result in a better macro- and microscopic homogeneity of the distribution of all compounds, yielding less waste-production
and a longer life-time of products.
In order to gain deeper insights in the process of “hipping” of the considered material and to see the distribution of both
main as well as trace components, 2D and 3D-SIMS measurements of the material were performed before and after having undergone
the hip process.
The measurements showed enrichments of Na, K, Mg, Ca, and S at the particle boundaries before as well as after the hip-process.
In the hipped material, the enrichments are significantly stronger in the spatial domains in-between larger particles. They
also reveal, that the concentration of C is not equal in all particles and that the particles are covered with an Al2O3-layer which is not dispersed by the hip-process. There were also found small (∼50–100 nm) nitride-precipitates before as
well as after the hip-process. 相似文献
2.
The present paper focuses on the characterisation of surface composition and alloying element in-depth distribution of water-atomised
Al–Zn–Mg–Cu alloy powders by secondary ion mass-spectrometry and Auger electron spectroscopy. A pronounced segregation of
Mg and some impurities (Fe, Ca, S) concurrently with some Zn depletion are observed on the powder surface. The oxide film
formed on the powder surface mainly consists of Al and Mg oxides. The film is non-uniform in thickness: rather coarse surface
oxide islands coexist with surface areas covered by a thin (<1.8 nm) oxide layer. The extent of surface oxidation is strongly
affected by solidification conditions: The average thickness of the surface oxides increases with increasing particle size
or with decreasing cooling rate. All alloying elements are homogeneously distributed in the bulk of individual particles.
No significant differences in chemical composition between different particles of a given powder are observed.
Received November 26, 1999. Revision September 25, 2001. 相似文献
3.
Thomas Kolber Kurt Piplits Leopold Palmetshofer Herbert Hutter 《Mikrochimica acta》2000,135(1-2):105-111
The distribution of the relevant elements within TiN coatings, made with two different physical deposition methods as the
conventional dc vacuum arc method and the filtered high current pulsed arc method (Φ-HCA) are characterized and finally compared.
Despite the rougher surface of the dc-arc produced TiN layer, which is due to accumulated droplets, there is no evidence of
different stoechiometric composition of Ti and N on the surface. The interface of the dc-arc produced TiN layer (600 nm) is
10 times wider than the one made with the new filtered high current pulsed arc method (60 nm). However the TiN layer made
by Φ-HCA shows an inhomogeneous distribution of aluminum and chlorine in the vertical direction, whereas the dc-arc sample
is homogeneous. Furthermore, the TiN layer made by Φ-HCA shows vertically an obvious local maximum of chlorine at a depth
of about 130 nm. This vertical local maximum has an homogeneous distribution in horizontal direction, which means that a thin,
chlorine enriched layer has been incorporated inside the TiN layer. Nevertheless, quantification by SIMS shows that aluminum
as well as chlorine concentrations of both samples are too low to influence any TiN properties.
Received January 3, 2000. Revision April 4, 2000. 相似文献
4.
Markus Pidun Norbert Lesch Silvia Richter Peter Karduck Wolfgang Bock Michael Kopnarski Peter Willich 《Mikrochimica acta》2000,132(2-4):429-434
A solar control coating was analysed by different methods of surface analysis with respect to the layer sequence and the
composition and thickness of each sublayer. The methods used for depth profiling were Auger electron spectroscopy, electron
probe microanalysis, secondary neutral mass spectroscopy and secondary ion mass spectroscopy based on MCs+. The structure of the coating was unknown at first. All methods found a system of two metallic Ag layers, embedded between
dielectric SnOX layers. Additionally, thin Ni-Cr layers of 1–2 nm were detected on top of the Ag layers. Thus the detected layer sequence
is SnOX/Ni-Cr/Ag/SnOX/Ni-Cr/Ag/SnOX/glass. The Ni:Cr ratio in the nm-thin layers could be quantified by every method, the Cr fraction corresponding to less than
one monolayer. We compare the capabilities and limitations of each method in routinely investigating this solar control coating.
Importance was attached to an effective investigation. Nevertheless, by combining all methods, measuring artefacts could be
uncovered and a comprehensive characterisation of the system was obtained. 相似文献
5.
Gabriele Tamborini Maria Wallenius Olivier Bildstein Leena Pajo Maria Betti 《Mikrochimica acta》2002,139(1-4):185-188
Methodologies based on secondary ion mass spectrometry (SIMS) for isotopic measurements in nuclear forensic applications
relevant to the age determination of Pu particles and isotopic composition of oxygen for geolocation assignment are described.
For the age determination of Pu particles, a relative sensitivity factor (RSF) to correct for the different ionisation efficiencies
of U and Pu, was obtained by analysing standard Pu materials with known ages. An RSF of 2.41±0.05 was obtained for PuO2 from measurements on samples with different Pu/U ratios. In a sample of known origin, using this RSF value, the age calculated
from the 238Pu/234U and 240Pu/236U ratios agreed well with the reported age of 2.3 years. For geolocation assignment, a new approach based on the measurement
of differences in the natural abundance of 18O and 16O isotopes and their ratio was developed. The instrumental mass discrimination of the 18O/16O ratio was determined using three O-isotope samples of different chemical composition. The measured precision (the standard
error of 100 cycles/analysis) obtained for the oxygen isotopic measurement on the samples was typically ±1.1‰. 相似文献
6.
Vacuum deposited films of immiscible metal–metal systems can be applied as tribological coatings for plain bearings in high
performance diesel engines. These industrially manufactured coatings show higher lifetimes than conventional electroplated
coatings. For our investigations we used aluminum-tin coatings of 1 μm thickness on a glass substrate produced by sequential
deposition from two separate targets under working gas pressure of 0.4 Pa. The tough Al matrix takes high mechanical loads
and the soft inclusions of Sn act as solid lubricant. While Sn is deposited it migrates on the Al surface and grows as islands.
We characterized the conformation and the distribution of the Sn islands on the surface and to the interstitial area between
the islands with 3-D secondary ion mass spectroscopy (SIMS). The existence of a Sn layer between the islands (“wetting layer”)
has been detected by SIMS and verified by measurements with Auger electron spectroscopy (AES). 相似文献
7.
Dagmar Dietrich Peter Willich Sabine Stöckel Kathrin Weise Günter Marx 《Mikrochimica acta》2000,133(1-4):183-186
A suitable fibre coating is essential to obtain optimal fibre-matrix interaction in fibre-strengthened composite materials.
Thin films (∼100 nm) of silicon carbide, turbostratic carbon, and boron nitride were deposited by CVD as single or double
layers on commercial multi-filament fibres in a continuous process. The fibre material itself may be carbon, alumina, silicon
carbide, or a quaternary ceramic of SiCBN. The application of MCs+-SIMS enables one to determine the composition (including impurities of H and O) of various fibre coating materials with an
accuracy of at least 20% relative. Due to the special geometry of the multi-filament samples the depth resolution of the SIMS
depth profiles is limited, nevertheless, layered structures and some details of the interface between coating and fibre can
be studied. The depth calibration of the SIMS depth profiles is derived from sputter rates established on flat samples with
a composition similar to that of the fibre coating material. However, the obtained film thicknesses are not extremely different
from the values derived from TEM on cross sections of coated fibres. 相似文献
8.
We use a multiple-analytical approach based on secondary-ion mass-spectrometry (SIMS), X-ray single-crystal structure refinement
(SREF) and electron-probe micro-analysis (EPMA) to derive the complete crystal-chemical formula of a B-rich kornerupine-group
mineral, prismatine, from Hrarigahy, Madagascar: (Ca0.01Li0.02Mg0.20Fe2+
0.10) (Mg3.57Fe2+
0.06 Al5.37) (Si3.84B0.91Al0.26)O21 (OH1.08F0.07). SIMS matrix effects related to crystal structure were investigated by analyzing two grains with a known crystallographic
orientation relative to the ion beam.
Boron orders at the T3 site. The refined site-scattering for T3, 6.33 eps (electrons per site) agrees well with the mean bond-length for this site (1.512 ?), which indicates nearly complete
occupancy by B (85% rel.). B2O3 (∼ 4 wt%), derived by SREF, agrees with the SIMS data within analytical uncertainty using Si as the inner reference for the
matrix. The occupancy of the X site obtained by combining the SIMS and EPMA data (5.30 eps; electrons per site) agrees with the refined site-scattering
value (5.75 eps). Trace quantities of Li and Ca are ordered at this site. SIMS data for H2O is in accord with the stoichiometric value, indicating complete occupancy at O10 by OH. Fluorine (∼ 0.17 wt%) orders at O10: it corresponds to ∼ 0.07 atoms per formula unit (apfu) vs. 0.15 apfu (atoms per formula unit) by SREF, indicating a slight
overestimation of F with SREF, as previously observed in fluoborite.
Our data show that SIMS chemical matrix effects are well-calibrated, and emphasize the usefulness of independent micro-analytical
techniques in testing the mutual accuracy and consistency of experimental data. 相似文献
9.
Secondary ion mass spectroscopy (SIMS) is a powerful method for element distribution examination of conducting and semi-conducting
surfaces at high spatial resolution and with a high sensitivity. Routine surface analysis produces about 8 to 15 images in
a short time, each of which displays the intensity distribution of one mass, thus generating a multispectral SIMS image. Formation
of occlusions, segregations, and the overall location of the elements relative to each other, are difficult to recognise when
looking at n separate 2-D images.
Image fusion is a process whereby images obtained from various sensors, or at different moments of time, or under different
conditions, are combined together to provide a more complete picture of the object under investigation. The process of combining
SIMS images may be viewed as an attempt to compensate for the inherent effect of SIMS to channel the information obtained
from the sample into different images, corresponding to different element phases.
The wavelet transform is a powerful method for fusion of images. This work covers the use of wavelet based fusion algorithms
on multispectral SIMS images, evaluating the performance of different wavelet based fusion rules on different type of image
systems and comparing the results to conventional fusion techniques. An aim of this study is to increase the information,
i.e. the number of masses, which can be merged into one image in order to enhance the perception and interpretation of the
SIMS surface images. 相似文献
10.
The content and the three dimensional distribution of impurities play an important role in the production process of high
purity rhenium powder (99.99% purity grade) and for its further use as alloying and coating agent in high temperature applications.
In this paper the characterization of raw Re granulate, Re powder, cleaned by heat treatment, Re coatings, produced by most
common preparation methods (PVD and VPS) and PM Re by means of SIMS is presented. The analysis of the three dimensional distribution
of trace elements is performed by 3D SIMS. The quantification of carbon, which was not possible with other analytical techniques
as a result of the high volatility of Re2O7 until now, has been carried out by SIMS depth profile analysis. It is discussed if internal standards, produced by introduction
of defined amounts of carbon soot to the Re powder lead to useful results. 相似文献
11.
Stanislav Kúdela Steffen Oswald Stanislav Kúdela Jr. Stefan Baunack Klaus Wetzig 《Mikrochimica acta》2000,133(1-4):29-34
Fibre/matrix interfaces in δ-Al2O3/Mg8Li and δ-Al2O3/Mg composites have been investigated using XPS and SIMS analysis of extracted δ-Al2O3 fibres in context with previous XRD observations. Results obtained indicate that in MgLi based composites lithium enters
preferentially the interfacial redox reactions producing Li+ ions that occupy vacant cation positions in the defect δ-Al2O3 lattice which results in a strong fibre/matrix interfacial bond. On the other hand, in Mg matrix composites the magnesium
oxide appears to be the final reaction product that does not enter the solid state reaction with adjacent δ-Al2O3 fibre during the melt infiltration process, so that only relatively weak interfacial bond is created. 相似文献
12.
Gabriele Tamborini 《Mikrochimica acta》2004,145(1-4):237-242
In the framework of the projects Environmental Sampling and High Performance Trace Analysis in support to the International Atomic Energy Agency (IAEA) and the Euratom Safeguards Office (ESO), the research has been focused on the identification and characterisation of particles of interest containing mainly U and other actinides.Multiple analyses, elemental and isotopic, of single radioactive particles in the µm-size range are key-tools in environmental research and in nuclear forensics. The main purpose in the analysis of single particles by SIMS is the determination of their isotopic composition that has been demonstrated successfully for uranium and plutonium particles. From these results, the enrichment of the material produced, the process used for the enrichment as well as the starting material employed (natural or reprocessed uranium) can be identified. 相似文献
13.
Jérôme Lamontagne Lionel Desgranges Christophe Valot Jean Noirot Thierry Blay Ingrid Roure Bertrand Pasquet 《Mikrochimica acta》2006,155(1-2):183-187
The behaviour of gases produced by fission is of great importance for nuclear fuel operation. Within this context, an experimental
method for the characterisation of the fission gas including gas bubbles in an irradiated UO2 nuclear fuel was developed in our laboratory using SIMS, EPMA and SEM results. SIMS and EPMA have been used to measure the
radial distribution of xenon and SEM gives information on bubble formation across the fuel pellet radius. Using SIMS, xenon
concentration can be determined in the matrix and in the bubbles. A quantification method, allowing the determination of the
total inventory of xenon, is proposed and qualified with EPMA results. It is concluded that the complementary micro-analytical
techniques SIMS, EPMA and SEM are very powerful tools for the characterisation of the fission gas bubbles in irradiated nuclear
fuel. 相似文献
14.
Stéphane Brémier Rachid Hasnaoui Stéphane Portier Olivier Bildstein Clive T. Walker 《Mikrochimica acta》2006,155(1-2):113-120
A CAMECA IMS 6F secondary ion mass spectrometer (SIMS) for the analysis of irradiated nuclear fuel has been installed in the
Microbeam Analysis Laboratory of the Institute for Transuranium Elements (ITU). This device is specially equipped with heavy
metal shielding to enable the safe examination of irradiated nuclear fuel samples with activities up to 75 GBq. At ITU the
shielded SIMS will be used in conjunction with EPMA taking advantage of the complementary nature of the two techniques and
will make important contributions to ongoing research programmes such as the safety of nuclear fuels, the partitioning and
transmutation programme and the characterisation of spent fuels. The paper describes the shielded SIMS installation and presents
a selection of results from the commissioning tests. 相似文献
15.
Jérôme Lamontagne Jean Noirot Lionel Desgranges Thierry Blay Bertrand Pasquet Ingrid Roure 《Mikrochimica acta》2004,145(1-4):91-94
The formation of gas bubbles is a key issue for nuclear fuel behaviour. The first measurements of xenon during a depth profile in irradiated nuclear fuel evidenced some peaks over a non-zero baseline. In comparison with EPMA mappings of xenon and SEM image of the sputtered surface, it is proven that the peaks correspond to bubbles while the baseline corresponds to xenon included in the UO2 matrix. 相似文献
16.
In April 1998 Raimond Castaing left the world of electrons, of ions and others particles, his wife and his family, his numerous
students, for the world of stars.
Raimond Castaing (Fig. 1) had a very strong personality. No one will forget their first meeting with him and all his students
remember how brilliant he was as a teacher. A lot of anecdotes about his famous hot temper are still circulating among his
friends and his former students. But in this paper, we would like to evoke Castaing’s memory through his achievements in Instrumental
Physics, from the time of his doctoral thesis to later developments with his students, which were all centred on the imaging
of the microstructures of materials and their quantitative chemical analysis. 相似文献
17.
The characterisation of disposable screen-printed electrodes for stripping analysis is described. The graphite surface of
the working electrode is used as substrate for plating a thin mercury film, which allows the electrochemical preconcentration
of heavy metals. Optimisation procedures and experimental results are presented. Detection limits around the ppb level were
obtained for different metals [Pb(II), Cd(II), Cu(II)].
Received June 6, 1998. Revision November 10, 1988. 相似文献
18.
Determination of Selenium Species in Environmental Samples 总被引:6,自引:0,他引:6
Krystyna Pyrzyńska 《Mikrochimica acta》2002,140(1-2):55-62
The essential nature of selenium as well as its toxicity depend on the concentration and the chemical forms in which this
element is present in a given sample. Dissolved inorganic selenium can be found in natural water and soil as selenides, selenite
and selenate. Organoselenium compounds present in air, soil and plants are volatile methylselenides, trimethylselenonium ion
and several selenoamino acids. This review is a summary of recent research on the determination of selenium species in environmental
samples such as water, air, soil and plants. Stability of selenium species in solutions and their storage is also discussed.
In the metabolic pathway in the body selenide could act as the common intermediate for inorganic and organic Se sources as
well as the checkpoint between further utilisation and excretion of selenium.
Received May 30, 2001; accepted October 19, 2001; published online July 15, 2002 相似文献
19.
The iodine-azide reaction induced by eight thiosemicarbazones was investigated. Inducing properties of thiosemicarbazones
are different and depend on the parent carbonyl compound used for synthesis. The inductor coefficients of the examined thiosemicarbazones
vary from 61 to 176. Optimum conditions for the determination of microamounts of thiosemicarbazones are given. The detection
limit for the determination by the back-titration method depends on the inducing activity and is 0.9 μg for phenyl-thiosemicarbazones
and 2 μg for diethyl-thiosemicarbazone in a 5-mL sample, and this corresponds to a concentration of 0.9 × 10−6 mol/L and , respectively. The automatic titration with the diluted iodine solution decreases the detection limit to about 50 ng in a
10-mL sample.
Received October 28, 1998. Revision April 9, 1999. 相似文献
20.
Mohamed S. Ibrahim Mohamed S. El-Maazawi Khaled M. Al-Magboul Moustafa M. Kamal 《Mikrochimica acta》2001,137(3-4):215-220
A sensitive method for the determination of amitraz pesticide at nanomolar level by adsorptive stripping voltammetry at a
hanging mercury drop electrode is described. The cyclic voltammograms demonstrate the adsorption of this compound on the mercury
electrode. A systematic study of the various experimental parameters, that affect the stripping response, was carried out
by differential pulse voltammetry. Using an accumulation potential of −0.50 V, and 30 s accumulation time, the limit of detection
was found to be 2.3 × 10−9 mol L−1 and the relative standard deviations (n = 5) was 2.2% at concentration level of 5.0 × 10−8 mol L−1 of amitraz. The influence of diverse ions and some other pesticides was investigated. Finally, the method was applied to
the determination of amitraz in spiked soil and water. The relative standard deviation is 4.5% for 5 determinations of amitraz
in water and 3.2% for 5 determinations in soil.
Received December 6, 2000. Revision March 1, 2001. 相似文献