scholarly journals Optical microscopy as a simple method for analysis of boiler tube failure

10.30544/461 ◽  
2020 ◽  
Vol 25 (04) ◽  
pp. 301-313
Author(s):  
Milan Jovanović ◽  
Zoran Mišković ◽  
Vesna Maksimović ◽  
Ivana Cvijović-Alagić
Keyword(s):  
Electron Microscopy ◽  
Optical Microscopy ◽  
Low Carbon Steel ◽  
Microstructural Characterization ◽  
Low Carbon ◽  
Boiler Tube ◽  
Simple Method ◽  
Microstructural Inhomogeneity ◽  
Steel Boiler ◽  
Scanning Electron

A severely damaged low carbon steel boiler tube was the object of this investigation. Detailed microstructural characterization was performed by optical microscopy, whereas scanning electron microscopy (SEM) was applied only in a few cases. Results show that a variety of microstructures was formed in the material of the damaged boiler tube during its exploitation. The failure of the tube is the result of very inhomogeneous overheating. The side of the boiler tube toward fire (F) was exposed to high overheating temperature, which in some locations was well above the A3 transformation temperature. The side toward boiler (BL) was subjected to lower temperatures, i.e. in the region mostly between A1 and A3 temperatures. Variations in temperatures and cooling rates, which resulted in microstructural inhomogeneity, are the main cause for the formation and multiplication of stresses leading to the rupture of the tube.

SEM Studies on the Microstructure and Phase Composition Distribution in Cr3C2 + TiC Claddings on Low-Carbon Steel

2020 ◽  
Vol 303 ◽  
pp. 59-66
Author(s):  
Konstantin V. Ivanov ◽  
Vladimir E. Ovcharenko
Keyword(s):  
Electron Microscopy ◽  
Phase Composition ◽  
Carbon Steel ◽  
Structural Parameters ◽  
Low Carbon Steel ◽  
Relativistic Energy ◽  
Low Carbon ◽  
Composition Distribution ◽  
X Ray ◽  
Scanning Electron

Using scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX) we studied the distribution of structural parameters, phase composition and alloying elements concentration across the coatings obtained by cladding of chromium and titanium carbides mixture on low-carbon steel. The beam of relativistic energy electrons extracted into the atmosphere was used to form the coatings. The homogeneity in the allying elements distribution is shown to be defined by the lifetime of the melt bath while the phase composition distribution depends on the thickness of the melt layer. Both above parameters are determined by the density of the entered energy.

Microstructures and Textures During Annealing in Low Carbon Al-Killed Steels with Low Finishing Temperatures and High Coiling Temperatures

2011 ◽  
Vol 194-196 ◽  
pp. 52-55 ◽  
Author(s):  
Bao Cai Wu ◽  
Feng Shi ◽  
Xin Yu Cheng ◽  
Rui Min Lin ◽  
Chun Ming Liu
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Optical Microscopy ◽  
Volume Fraction ◽  
Low Carbon ◽  
Coiling Temperature ◽  
X Ray ◽  
Obvious Advantage ◽  
Equiaxed Grain ◽  
Scanning Electron

Microstructures and textures after annealing at 680°C in low carbon Al-killed steels with low finishing temperature and high coiling temperature were investigated by means of optical microscopy (OM), scanning electron microscopy (SEM) and X-Ray Diffractometer (XRD). The results show that higher coiling temperature and lower finishing temperature can both cause the appearance of equiaxed grain and line cementite. The equiaxed grain in 2# steel with higher coiling temperature is the more obvious. Advantage textures are weak in the steels with higher coiling temperature and lower finishing temperature and volume fraction of {111}fiber in 2# steel with higher coiling temperature is only 7.17%, so the stamping property should be worse.

Effect of Cutting Speed during Turning of Low Carbon Steel on Mechanical Properties and Surface Roughness

2015 ◽  
Vol 1096 ◽  
pp. 340-345
Author(s):  
Zakaria Boumerzoug ◽  
Fethi Remli ◽  
Fabienne Delaunois
Keyword(s):  
Electron Microscopy ◽  
Mechanical Properties ◽  
Scanning Electron Microscopy ◽  
Surface Roughness ◽  
Surface Layer ◽  
Cutting Speed ◽  
Low Carbon Steel ◽  
Low Carbon ◽  
Speed Effect ◽  
Scanning Electron

The purpose of this paper is to study the cutting speed effect on mechanical and surface roughness (Ra) of XC18 steel. Scanning electron microscopy, hardness and roughness tests were used. We have found that the cutting speed affects the surface layer of a workpiece, induces hardening of the surface, and increases the surface roughness.

Digital imaging: When should one take the plunge?

1996 ◽  
Vol 54 ◽  
pp. 602-603
Author(s):  
John F. Mansfield
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Optical Microscopy ◽  
Digital Imaging ◽  
Storage Devices ◽  
Major Benefit ◽  
Transmission Electron ◽  
New Instrument ◽  
Scanning Electron

The current imaging trend in optical microscopy, scanning electron microscopy (SEM) or transmission electron microscopy (TEM) is to record all data digitally. Most manufacturers currently market digital acquisition systems with their microscope packages. The advantages of digital acquisition include: almost instant viewing of the data as a high-quaity positive image (a major benefit when compared to TEM images recorded onto film, where one must wait until after the microscope session to develop the images); the ability to readily quantify features in the images and measure intensities; and extremely compact storage (removable 5.25” storage devices which now can hold up to several gigabytes of data).The problem for many researchers, however, is that they have perfectly serviceable microscopes that they routinely use that have no digital imaging capabilities with little hope of purchasing a new instrument.

Investigation of Die Tilting of Packages with Single and Multi-chips

2018 ◽  
Author(s):  
Lo Chea Wee ◽  
Tan Sze Yee ◽  
Gan Sue Yin ◽  
Goh Cin Sheng
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Electron Beam ◽  
Optical Microscopy ◽  
Device Performance ◽  
Electronic Components ◽  
Area Of Interest ◽  
On Chip ◽  
Scanning Electron

Abstract Advanced package technology often includes multi-chips in one package to accommodate the technology demand on size & functionality. Die tilting leads to poor device performance for all kinds of multi-chip packages such as chip by chip (CbC), chip on chip (CoC), and the package with both CbC and CoC. Traditional die tilting measured by optical microscopy and scanning electron microscopy has capability issue due to wave or electron beam blocking at area of interest by electronic components nearby. In this paper, the feasibility of using profilemeter to investigate die tilting in single and multi-chips is demonstrated. Our results validate that the profilemeter is the most profound metrology for die tilting analysis especially on multi-chip packages, and can achieve an accuracy of <2μm comparable to SEM.

The External Morphology of the Eggs of Culex (Culex) saltanensis (Diptera: Culicidae) Under Scanning Electron Microscopy

2020 ◽  
Author(s):  
J R Santos-Mallet ◽  
T D Balthazar ◽  
A A Oliveira ◽  
W A Marques ◽  
A Q Bastos ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Optical Microscopy ◽  
Osmium Tetroxide ◽  
Neotropical Region ◽  
External Morphology ◽  
Metal Supports ◽  
Scanning Electron

Abstract The aim of the present study was to describe the morphology of the eggs of Culex (Culex) saltanensis Dyar that occurs in the Neotropical region. Eggs of the Cx. (Cux.) saltanensis were collected at the Mata Atlântica FIOCRUZ campus, fixed in 1% osmium tetroxide, prepared for mounting on metal supports, observed under a scanning electron microscope, and described morphologically. The eggs had a coniform shape with a length of approximately 0.5 mm (505–510 µm) and a width in the median portion of 117 µm (113–123 µm). Upper portion is lined with tubers of irregular shape and varying sizes (0.64–1.31 µm), located on a cross-linked matrix forming bands observed under optical microscopy. The micropyle is encased in a necklace of approximately 6.6-µm plates arranged in a flower-like shape. Comparing Cx. (Cux.) saltanensis eggs with several species of different genera, important divergent characteristics can be observed. However, this study points to the need for new descriptions of eggs of species belonging to the same subgenus in order to analyze if there will be differences between them. Culex (Cux.) saltanensis eggs have particular characteristics not observed in eggs of other Culicidae genera.

Damage Analysis of Heat Resistant Steels

2007 ◽  
Vol 537-538 ◽  
pp. 303-306
Author(s):  
Tamás Bíró ◽  
László Dévényi
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Optical Microscopy ◽  
Damage Analysis ◽  
Resistant Steel ◽  
Heat Resistant Steel ◽  
Advantages And Disadvantages ◽  
Heat Resistant ◽  
Heat Resistant Steels ◽  
Scanning Electron

This paper shows the result of some metallographical examinations that have been carried out on low-alloyed Cr-Mo-V heat resistant steel. The aim of this research is to present and compare the advantages and disadvantages of the mainly applied metallographical methods. These techniques are optical microscopy, scanning electron microscopy, replica method and special applications of these methods. We have proved that using the investigated methods together gives much more information about the lifetime of the specimen than using these techniques particularly.

scholarly journals Digital Imaging: When Should One Take The Plunge?

1997 ◽  
Vol 5 (4) ◽  
pp. 14-15
Author(s):  
John F. Mansfield
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Optical Microscopy ◽  
Digital Imaging ◽  
High Quality ◽  
Storage Devices ◽  
Major Benefit ◽  
Transmission Electron ◽  
Scanning Electron

The current imaging trend in optical microscopy, scanning electron microscopy (SEM) or transmission electron microscopy (TEM) is to record all data digitally. Most manufacturers currently market digital acquisition systems with their microscope packages. The advantages of digital acquisition include: almost instant viewing of the data as a high-quality positive image (a major benefit when compared to TEM images recorded onto film, where one must wait until after the microscope session to develop the images); the ability to readily quantify features in the images and measure intensities; and extremely compact storage (removable 5.25” storage devices which now can hold up to several gigabytes of data).

Identification of Nd163 phase in melt-textured NdBa2Cu3O7−δ bulk samples

2003 ◽  
Vol 18 (9) ◽  
pp. 2050-2054 ◽  
Author(s):  
Marcello Gombos ◽  
Vicente Gomis ◽  
Anna Esther Carrillo ◽  
Antonio Vecchione ◽  
Sandro Pace ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Optical Microscopy ◽  
Room Temperature ◽  
Polarized Light ◽  
Energy Dispersive ◽  
X Ray ◽  
Spontaneous Formation ◽  
The Stability ◽  
Scanning Electron

In this work, we report on the observation of Nd1Ba6Cu3O10,5 (Nd163) phase of the NdBaCuO system in melt-textured Nd123 bulk samples grown from a mixture of Nd123 and Nd210 phase powders. The observation was performed with polarized light optical microscopy and scanning electron microscopy–energy dispersive x-ray analyses. Images of the identified phase crystals show an aspect quite different from Nd422 crystals. Unexpectedly, Nd163 was individuated, even in “pure” Nd123 samples. Moreover, after long exposure to air, Nd163 disappeared completely in samples synthesized from powders containing Nd210. Thermogravimetry analyses of powders show that the stability of this phase in air is limited to temperatures higher than 900 °C, so Nd163 is unstable and highly reactive at room temperature. Moreover, an explanation of the observation of Nd163 in Nd210 free samples, based on the spontaneous formation of Nd163 phase in a Nd123 melt, is proposed.

Measuring Coral Skeletal Architecture Using Image Analysis v1

2021 ◽  
Author(s):  
Rowan Mclachlan ◽  
Ashruti Patel ◽  
Andrea G Grottoli
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Image Analysis ◽  
Scleractinian Coral ◽  
Coral Species ◽  
Energy Materials ◽  
Simple Method ◽  
Coral Skeletons ◽  
Skeletal Structures ◽  
Scanning Electron

Coral morphology is influenced by genetics, the environment, or the interaction of both, and thus is highly variable. This protocol outlines a non-destructive and relatively simple method for measuring Scleractinian coral sub-corallite skeletal structures (such as the septa length, theca thickness, and corallite diameter, etc.) using digital images produced as a result of digital microscopy or from scanning electron microscopy. This method uses X and Y coordinates of points placed onto photomicrographs to automatically calculate the length and/or diameter of a variety of sub-corallite skeletal structures in the Scleractinian coral Porites lobata. However, this protocol can be easily adapted for other coral species - the only difference may be the specific skeletal structures that are measured (for example, not all coral species have a pronounced columella or pali, or even circular corallites). This protocol is adapted from the methods described in Forsman et al. (2015) & Tisthammer et al. (2018). There are 4 steps to this protocol: 1) Removal of Organic Tissue from Coral Skeletons 2) Imaging of Coral Skeletons 3) Photomicrograph Image Analysis 4) Calculation of Corallite Microstructure Size This protocol was written by Dr. Rowan McLachlan and was reviewed by Ashruti Patel and Dr. Andréa Grottoli. Acknowledgments Leica DMS 1000 and Scanning Electron Microscopy photomicrographs used in this protocol were acquired at the Subsurface Energy Materials Characterization and Analysis Laboratory (SEMCAL), School of Earth Sciences at The Ohio State University, Ohio, USA. I would like to thank Dr. Julie Sheets, Dr. Sue Welch, and Dr. David Cole for training me on the use of these instruments.

Sign in / Sign up

Export Citation Format

Share Document