Application of new techniques for characterization of non-metallic inclusions in steel

When the quantitative characterization of non-metallic inclusions in steel is done and the effect of limiting factors is assessed, and based on that the possibility of reconstruction of the total content of non-metallic inclusions in steel is estimated, further considerations can be directed towards predicting the model of size distribution curve. The aim of this work is to establish relations on the basis of which it will be possible to quantify the content of non-metallic inclusions in extra-pure steels, when metallographic control is difficult or even impossible by routine procedures.

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Microstructural characterization of CoPtCr/Cr thin film disks by cross-section TEM and elongated probe micro-diffraction

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100088129 ◽

1991 ◽

Vol 49 ◽

pp. 762-763

Author(s):

M.A. Parker ◽

K.E. Johnson ◽

C. Hwang ◽

A. Bermea

Keyword(s):

Magnetic Recording ◽

Electron Probe ◽

Microstructural Characterization ◽

Crystallographic Structure ◽

Recording Media ◽

Layer By Layer ◽

Cross Sectional ◽

New Techniques ◽

Polished Side

We have reported the dependence of the magnetic and recording properties of CoPtCr recording media on the thickness of the Cr underlayer. It was inferred from XRD data that grain-to-grain epitaxy of the Cr with the CoPtCr was responsible for the interaction observed between these layers. However, no cross-sectional TEM (XTEM) work was performed to confirm this inference. In this paper, we report the application of new techniques for preparing XTEM specimens from actual magnetic recording disks, and for layer-by-layer micro-diffraction with an electron probe elongated parallel to the surface of the deposited structure which elucidate the effect of the crystallographic structure of the Cr on that of the CoPtCr.XTEM specimens were prepared from magnetic recording disks by modifying a technique used to prepare semiconductor specimens. After 3mm disks were prepared per the standard XTEM procedure, these disks were then lapped using a tripod polishing device. A grid with a single 1mmx2mm hole was then glued with M-bond 610 to the polished side of the disk.

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Physical Failure Analysis Techniques for Front-End-of-Line Defect Analysis

ISTFA 2016: Conference Proceedings from the 42nd International Symposium for Testing and Failure Analysis ◽

10.31399/asm.cp.istfa2016p0182 ◽

2016 ◽

Author(s):

Dirk Doyle ◽

Lawrence Benedict ◽

Fritz Christian Awitan

Keyword(s):

Cross Section ◽

Focused Ion Beam ◽

Ion Beam ◽

Gate Oxide ◽

Top Down ◽

New Techniques ◽

First Case ◽

Transmission Electron ◽

Scanning Transmission

Abstract Novel techniques to expose substrate-level defects are presented in this paper. New techniques such as inter-layer dielectric (ILD) thinning, high keV imaging, and XeF2 poly etch overflow are introduced. We describe these techniques as applied to two different defects types at FEOL. In the first case, by using ILD thinning and high keV imaging, coupled with focused ion beam (FIB) cross section and scanning transmission electron microscopy (STEM,) we were able to judge where to sample for TEM from a top down perspective while simultaneously providing the top down images giving both perspectives on the same sample. In the second case we show retention of the poly Si short after removal of CoSi2 formation on poly. Removal of the CoSi2 exposes the poly Si such that we can utilize XeF2 to remove poly without damaging gate oxide to reveal pinhole defects in the gate oxide. Overall, using these techniques have led to 1) increased chances of successfully finding the defects, 2) better characterization of the defects by having a planar view perspective and 3) reduced time in localizing defects compared to performing cross section alone.

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Characterization of Non‐Metallic Inclusions in Low‐Alloyed Steels by using PDA/OES and Offline Investigation Methods

steel research international ◽

10.1002/srin.202100223 ◽

2021 ◽

Author(s):

Hongying Du ◽

Annika Yang ◽

Andrey V. Karasev ◽

Pär G. Jönsson

Keyword(s):

Metallic Inclusions ◽

Investigation Methods

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A tool for finding inclusion clusters in steel SEM specimens

Open Engineering ◽

10.1515/eng-2020-0068 ◽

2020 ◽

Vol 10 (1) ◽

pp. 642-648

Author(s):

Anna-Mari Wartiainen ◽

Markus Harju ◽

Satu Tamminen ◽

Leena Määttä ◽

Tuomas Alatarvas ◽

...

Keyword(s):

Prediction Models ◽

Microscopic Analysis ◽

Steel Specimen ◽

Sem Analysis ◽

Quality Prediction ◽

Automatic Production ◽

Automatic Interpretation ◽

Metallic Inclusions ◽

Purity Analysis ◽

Inclusions In Steel

AbstractNon-metallic inclusions, especially large or clustered inclusions, in steel are usually harmful. Thus, the microscopic analysis of test specimens is an important part of the quality control. This steel purity analysis produces a large amount of individual inclusion information for each test specimen. The interpretation of the results is laborious and the comparison of larger product groups practically impossible. The purpose of this study was to develop an easy-to-use tool for automatic interpretation of the SEM analysis to differentiate clustered and large inclusions information from the manifold individual inclusion information. Because of the large variety of the potential users, the tool needs to be applicable for any steel grade and application, both for liquid and final product specimen, to analyse automatically steel specimen inclusions, especially inclusion clusters, based on the INCA Feature program produced data from SEM/EDS. The developed tool can be used to improve the controlling of the steel purity or for automatic production of new inclusion cluster features that can be utilised further in quality prediction models, for example.

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Removal of Ni(II) from aqueous solution using Moringa oleifera seeds as a bioadsorbent

Water Science & Technology ◽

10.2166/wst.2012.026 ◽

2012 ◽

Vol 65 (8) ◽

pp. 1435-1440 ◽

Cited By ~ 7

Author(s):

Thiago L. Marques ◽

Vanessa N. Alves ◽

Luciana M. Coelho ◽

Nívia M. M. Coelho

Keyword(s):

Moringa Oleifera ◽

Low Cost ◽

Ease Of Use ◽

Toxic Waste ◽

Adsorption Model ◽

New Techniques ◽

Sorption Data ◽

Natural Adsorbents ◽

Ph Range

Metal contaminants are generally removed from effluents by chemical and physical processes which are often associated with disadvantages such as the use of toxic reagents, generation of toxic waste and high costs. Hence, new techniques have been developed, among them the study of natural adsorbents, for instance, the use of Moringa oleifera seeds. The potential of M. oleifera seeds for nickel removal in aqueous systems was investigated. The seeds utilized were obtained from plants grown in Uberlândia/Brazil. After being dried and pulverized, the seeds were treated with 0.1 mol/L NaOH. Fourier transform infrared spectroscopy, scanning electron microscopy and thermogravimetric analyses were used for the characterization of the material. Using the optimized methodology (50 mL of 4.0 mg/L Ni(II), pH range of 4.0–6.0, agitation time of 5 min and adsorption mass of 2.0 g) more than 90% of Ni(II) could be removed from water samples. The sorption data were fitted satisfactorily by the Langmuir adsorption model. Evaluation applying the Langmuir equation gave the monolayer sorption capacity as 29.6 mg/g. The results indicate that this material could be employed in the extraction of nickel, considering its ease of use, low cost and environmental viability, which make it highly attractive for application in developing countries.

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