Spark Spectrometer Research Articles

Effect of case hardening on the wear and hardness properties of medium carbon steel for bone crushing application

The majority of wear-related problems are connected to crushing machines because hammer failure frequently causes machine failure which eventually leads to machine downtime. Therefore, improving the reliability of crushing materials is necessary for effective production. This research investigation focused on the development of crushing material with appropriate strength properties that can function in critical, impact-prone, corrosive, and abrasive conditions. The current study used palm kernel shell, coconut shell, and sawdust powder as the media for medium carbon steel in order to valorize the agro waste. Carburising media PKS-composition, CS-composition, and SD-composition were changed to 40%: 30%: 30%, PKS-composition 100%, CS-composition 100%, and SD-composition 100%. The process was carried out in 1 h (60 mims), 1 h:30 min (90 min), 2 h (120 min), 2 h:30 (150 min), and 3 h (180 min) soak period with varied carburising temperatures of 900, 950, 1000, and 1050 °C. However, several characterisation and mechanical tests were carried out using an optical microscope, a spark spectrometer, a scanning electron microscope coupled with an energy dispersive spectrometer, wear tester to explore their microstructural features. Vicker's hardness tester, sliding wear tester, and a thermal gravimetric analysis testing machine were also employed. In order to establish reasons for failure other than the cyclic loading on the materials, the results were compared with the properties of as-received un-failed, and carburised medium carbon steel. The results of carburisation show that PKS penetrates carbon at a rate that is noticeably higher than that of other materials at various temperatures and times, indicating that carbon diffuses deeply into the material. Hence, this enhances the wear resistance, and sample's hardness number but decreased its impact toughness respectively.

Fatigue Failure Analysis of Shaft in As-developed Wind Turbine with Reinforced-welding Elbow

This paper reports the fatigue analysis for a failure of a shaft in a wind turbine in which reinforced-welding elbow to support the shaft load. The shaft was broken near the reinforcing elbow. When designing mechanical and structural components, the diameter and the characteristics of materials have been considered not to exceed the permissible limit. However, after 40 days of the cycle operation, the shaft was broken at the accepted loading conditions within reasonable limits at a wind speed of 6-10 m/s. The crack initiate fatigue in the shaft is influenced by many variables that may due to uniaxial, bending, torsion, the shape of loading curve, part size, part finish, operating temperature, and atmosphere. For these reasons, it is important to investigate the fatigue behavior on the failure of the shaft. The main goal is to investigate and analyze the fatigue behavior on a broken shaft of the wind turbine gearbox to determine the features that cause the failure. A microscopic investigation of the fatigue-fracture surface was done. The microscopic analysis was carried out in terms of the chemical composition using ARL Spark Spectrometer, energy dispersive spectroscopy (EDS), the morphology of the fatigue by using scanning electron microscopy (SEM) and hardness test. Moreover, a theoretical analysis was made to illustrate the results and comparison between these results and the corresponding stress distribution data from a finite element method (FEM) simulation to know how the fatigue fracture began and propagated along the shaft. The result of the analysis shows that the fatigue occurred due to the unbalanced of the bending and torsion stress in the junction of the reinforced-welding elbow with hardness testing at the extreme cracking area is 435 HV. It is emphasized that the microstructure of fatigue surface structure shows sensitization to facilitate intergranular cracking and fatigue corrosion.

Analysis of aluminum alloys on a Polyvac E980 (Hilger Analytical) atomic emission spectrometer modified with a multi-channel analyzer of emission spectra (MAES)

A Polyvac E980 (Hilger Analytical) photoelectric vacuum optical emission spectrometer has been modified with a multichannel analyzer of emission spectra (MAES). The line of argon supply to the spark stand has been completely renewed. A precision mass flow controller with a microprocessor control unit has been installed to adjust the argon supply for different operation modes and fix the current values with the possibility of saving data for each spectrum. The microprocessor control unit coordinates the operation of the control lines and interrupts the operation of the spark generator when the stand is open or argon is absent. The modified vacuum spark spectrometer, originally designed for the analysis of iron-based alloys, has become suitable for determining the composition of non-ferrous alloys. Analytical programs have been developed for the rapid spectral analysis of AK12M2 and AK9ch aluminum alloys. The main methodological difficulty of the analysis is attributed to the necessity of monitoring high concentrations of silicon, copper, and iron along with the content of calcium impurity in the same sample. Calcium has a negative effect on the quality of castings, thus making the possibility of Ca determination an important motivation for the modification. After the preparatory work and the construction of calibration curves, the short-term and long-term repeatability of the results of spectral analysis of standard samples of aluminum alloys has been studied on the modified spectrometer. The results completely meet the standard requirements for determining the composition of aluminum alloys.

Analiza zmęczeniowa półosi napędowej samochodu osobowego

The subject of the research was the fatigue crack of the rear driveshafts in a BMW E36 car with a 2.5 L engine in sports driving conditions. The genesis of the work is the author's own experience, with the common type of damage to the driveshaft, consisting in fatigue-related twisting. The analysis was aimed at deter-mining the causes of fatigue failure. Additionally, the work proposes design changes that can improve fatigue properties. As part of the research, the analysis of steel composition with a spark spectrometer, analytical calculations identifying the stress state at the fracture site, fatigue calculations, FEM calculations and frac-tographic analysis of fatigue fractures were performed.

Accounting for Interelement Interferences in Atomic Emission Spectroscopy: A Nonlinear Theory

The article describes a nonlinear theory of how the presence of third elements affects the results of analyzing the elemental composition of substances by means of atomic emission spectroscopy. The theory is based on the assumption that there is an arbitrary relationship between the intensity of the analytical line of the analyte and the concentration of impurities and alloying elements. The theory has been tested on a simulation problem using commercially available equipment (the SPAS-05 spark spectrometer). By comparing the proposed algorithm with the traditional one, which assumes that there is a linear relationship between the intensity of the analytical line of the analyte and the intensities of the spectral lines (or concentrations) in the substance, it was revealed that there is a severalfold decrease in the deviations of nominal impurity concentrations from the measured ones. The results of this study allow for reducing the number of analytical procedures used in analyzing materials that have different compositions and the same matrix element. For instance, it becomes possible to determine the composition of iron-based alloys (low-alloy and carbon steels; high-speed steels; high-alloy, and heat-resistant steels) using one calibration curve within the framework of a universal analytical method.

Interfacial characterization and erosive wear performance of zirconia toughened alumina ceramics particles reinforced high chromium white cast irons composites

To investigate the erosive wear-corrosion behavior of ZTAP ceramic reinforced high chromium cast iron matrix composites in two types of sand at various rotational speeds, the ZTAP/Fe composites were fabricated. The interface characteristics, erosion wear-corrosion and erosive wear mechanism have been investigated in a slurry condition at various erosion rotational speeds. The chemical composition of the matrix material was determined using a spark spectrometer. SEM, TEM, 3D laser scanning microscope and AFM were used to analyze the microstructure characteristics and worn surface morphology of the composites. Furthermore, the wear loss rate and relative erosive wear resistance of ZTAP/Fe composites and Cr15 standard specimen measurements were conducted. The results showed that the interface between the ZTAP ceramics and the Cr15 matrix exhibits a continuous transition layer without visible defects and close contacts. In the case of SiO2 and SiC abrasive sand, the wear rate of ZTAP/Fe composites and Cr15 standard specimens increases with erosion time. The wear rate of ZTAP/Fe against SiO2 sand is lower than that of against SiC sand. ZTAP/Fe composites was found to exhibit a better corrosion resistance property than that of Cr15 standard specimens.

Acoustic emission assessment of measurement errors caused by gaps in chemical composition analyzes carried out using a portable spark spectrometer

During in situ tests, it was observed that the chemical composition analysis results obtained using a portable spark spectrometer significantly varied as the distance between the tested surface and the spectrometer probe nozzle increased. It was also observed that the nature of the sound emitted during the burning process was altered with the variation of this distance. Based on the Huygens-Fresnel principle, it was supposed that frequencies of the sound emitted during the burning process, as well as its magnitudes may be directly related to the quality of the chemical composition results. This paper investigated the relation between the errors associated with the results of chemical composition analyzes and the pressure of the leaked sound, since both depend on the gap thickness. The study was based on a full factorial design 3 × 8, where the test surface shape was investigated on three levels (flat; 220 mm diameter cylindrical and 325 mm diameter cylindrical) and the vertical distance factor was evaluated on eight levels (0 mm; 0.1 mm; 0.2 mm; 0.3 mm; 0.4 mm; 0.5 mm; 0.6 mm; 0.7 mm). During the tests, frequencies of the emitted sound signals were monitored using a precision microphone and a data acquisition module. The Analysis of Variance showed with a 95% confidence level that the investigated factors (vertical distance and test surface shape) and the interaction between them produced statistically significant effects in the values of the response variable (wt%) of the X65 steel. The Kruskal-Wallis and Mann-Whitney U tests showed that at least one experiment exhibited a mean value different from others and a significant number of pairs presented differences between the means. Through the analysis of acoustic sound signals, the validity of the measurement results was evaluated. An acceptance criterion based on relative error in wt% of chemical composition was defined.

Influence of the Environment on the Operational Safety of a Fluidized Bed Boiler

Abstract The use of fluidized bed boilers in modern power engineering is a promising solution for clean and economically acceptable combustion of various fuels, including coal, biomass and waste, for the generation of electricity. The fluidized bed boilers are nowadays technically advanced and complex combustion facilities where all individual boiler elements are subjected to withstand continuous structural and thermal loads during their operation. Intensive loading of boiler elements can be quite easily linked with boiler operational safety and is quite often one of the main reasons for emergency shutdowns followed by necessary replacements of the damaged items. In case of industrial large-scale circulating fluidized bed boilers the frequency of unplanned shutdowns is also quite often affected by the hydrodynamics of the fluidized bed and some other parameters, such as the intensity of solids circulation, temperature, solids concentration, flue gas composition and velocity, solids accumulation and deposition, as well as the corrosion or erosion of heat transfer surfaces. The present paper briefly reports the results of authors investigation focused on the morphology and structure of some chosen elements (steel anchors) sampled from one of Polish circulating fluidized bed boilers. The anchors were degraded during boiler operation and lost their mechanical durability. In order to determine the reasons of anchors’ degradation chemical composition of the elements was determined with the use of a spark spectrometer SPECTROLAB and sample morphology was investigated with JEOL JSM-6610LV scanning microscope equipped with LaB6 cathode.

Determinación De La Capacidad Mecánica De Las Bielas De Los Vehículos Kia Rio, Corsa Evolution Y Volkswagen Gol Mediante FEM Y Ensayos Experimentales

Este artículo se basa en la determinación de la capacidad mecánica que soportan las bielas de los vehículos Kia Rio, Corsa Evolution y Volkswagen Gol, en base a un análisis estático por compresión y pandeo en condiciones de columna, determinando si existe o no sobredimensionamiento de estas. El estudio se desarrolla en fases:
 - Análisis químico realizado por un espectrómetro de chispa, ensayos de dureza del material y análisis micrográfico basado en normas ASTM, determinando el material específico de cada biela.
 - Cálculo analítico determinando la presión y fuerza de explosión en el motor.
 - Análisis de las bielas en condiciones de columna logrando obtener valores críticos a los cuales las bielas empezarán a pandearse, estos valores son analizados mediante FEM pudiendo determinar los factores de seguridad para cada caso.
 - Modelado y Análisis FEM a compresión de cada Biela con incremento de carga hasta obtener los valores de esfuerzo, desplazamiento y factor de seguridad últimos.
 - Realización de ensayos no destructivos por tintas penetrantes y partículas magnéticas basado en normas ASTM determinando si existe o no posibles fisuras o porosidades que influencien en los resultados.
 - Ensayo experimental a compresión en la máquina de ensayos universales obteniendo resultados que serán comparados con los obtenidos mediante FEM.
 - Comprobación de sobredimensionamiento en las bielas mediante comparación de esfuerzos obtenido del ensayo experimental y mediante FEM considerando la fuerza en el ciclo de expansión.
 - Determinación de un modelo matemático usando regresiones lineales del cual obtendremos el esfuerzo en función de la fuerza de compresión que ingresemos.

Preliminary Results on Microstructural, Chemical and Wear Analyze of New Cast Iron with Chromium Addition

A new cast-iron material was obtained by melting in an induction furnace. The material was microstructural and chemical characterized before and after a wear test. We analyze the chemical composition of the material at macro-scale using a Spark Spectrometer and at micro-scale using Dispersive Energy Spectrometer. Microstructure before and after the external solicitations was observed using a Scanning Electron Microscope. We also evaluate the influence of external force on the dendrites microstructural and chemical modification.

COMPLEX MODIFICATION OF SECONDARY SILUMINS

Purpose. Development of scientific and technological bases of formation of the specified secondary hypoeutectic (АK8M3) and eutectic (АК12М2MgН) silumins' structure; and increasing their mechanical and service properties' indices in the cast state and after heat treatment up to the level of primary alloys. Methodology. Determination of the chemical composition was conducted by spectral analysis on the spark spectrometer «SPECTROLAB» (Germany). Metallographic analysis was performed on the microscopes МIМ-7 and МIМ-8, and also by the high definition metallography method using the raster electronic microscope «JSMT-300» (Japan). Heat treatment of aluminum alloys was carried out applying T1 and T5 modes according to State Standard of Ukraine 2839-94 (GOST 1583-93). Standard techniques were used during the determination of mechanical properties. The temperature coefficient of linear expansion for the piston alloy АK12М2МgH (AL25) was determined using the specimens Ø with the diameter of 3.5 mm and length of 50 mm with the use of Shevenard optical quartz dilatometer. High temperature fracture resistance was determined according to State Standard 10145-81 as the time before fracture of the specimen at specified stress of 50 MPa and temperature of 300°С. Findings. The technology of obtaining alloys from charge, which consists of 100 % scrap and production wastes has been developed and implemented into production. This technology provides obtaining of metal of the guaranteed chemical composition and high quality with the reduction of energy costs for melting. Originality. The regularities of the formation of the structural and phase state and the level of physical and mechanical properties of eutectic and secondary hypoeutectic silumins depending on the refining and modifying processes have been established. The generalization of regularities of the secondary silumins' fracture has been carried out. Quantitative characteristics of the intermetallic phases' role in the fracture mechanisms and aluminum alloys' mechanical properties level formation have been obtained. Practical value. Structure formation processes of secondary aluminium alloys depending on their production technology have been studied. Highly efficient refining and modifying complexes for treatment of secondary hypoeutectic and eutectic aluminum alloys have been developed and the optimal quantity of modifiers depending on the charge quality has been determined.

Spark spectrometry of toxic smokes: towards a portable, inexpensive, and high-resolution environment monitoring instrument

Inductively coupled plasma mass spectrometry and laser-induced breakdown spectroscopy are the most popular techniques for monitoring toxic gases in the environments. Apart from sensitivity and resolution of the techniques, they suffer from several issues including portability and high cost. For design and realization of a low cost, spark spectrometry based portable instrument for monitoring toxic gases in our environments is the main motive of the present work. We have introduced several toxic smokes into a gas chamber containing our developed instrument. We have also investigated the capability of the instrument for online analysis of suspended particulate matter as well as various gaseous elements in the smokes. We have also developed software for the practical interface. The apparatus has been successfully tested to monitor several toxic fumes including cigarette smoke and NOx. It has also been demonstrated that the instrument is equally efficient to monitor air quality in the open environment, for example, presence of nitrogen, oxygen, and water vapor in the ambient condition. In the present work, we have demonstrated some important spectroscopic studies including role of water vapor (solvation) in the ionization of potassium, which is an active ingredient of toxic smokes, in the ionization which leading to the generation of atomic emission under the spark spectrometer can also be achieved with our instrument. The sensitivity of the instrument is found to be sub ppm (0.27 ± 0.13 ppm) in the case of cigarette smoke in ambient condition. The simplicity and extremely cost-effective design can provide an alternative method of detection of fumes in air and can serve as a cheap alternative for costly/bulky bench-top instruments.

Resonance behavior of a K S K S system near the mass 1775 MeV

The preliminary results of an investigation of a system of two K S mesons in the mass interval 1600–1950 MeV are reported. The events were obtained on a 6-m magnetic spark spectrometer at ITEP in π − p interactions at 40 GeV, using a neutral trigger which suppressed both charged particles and γ rays. A peak of width ≃30 MeV with statistical significance not lower than six standard deviations is observed with momentum transfer selection |tu|0.23 GeV2 near the mass 1775 MeV of the K S K S system. The observed phenomena can be interpreted as the existence of one resonance with the indicated parameters, or two narrower resonances. In the latter case, their masses are 1768±1.5 and 1787±1.5 MeV. The widths of these states are comparable to the mass resolution of the spectrometer (∼5 MeV). Estimates of the product σ ⋅BR(K S K S ) give ∼1.5 and 2.5 nb, respectively, for the first and second states.

Embedding of small samples for spark discharge atomic emission spectrometry

One approach to the analysis of small samples by means of an ordinary point-to-plane spark spectrometer is by embedding them in an electrically conductive material. In order to do so for steel samples of any shape, embedding in a pure tin ingot was found to be appropriate. This was carried out by putting them into a graphite crucible along with fairly large tin pieces, followed by heating above the melting point of tin. Thus the samples became firmly attached to the tin ingots. Grinding was easy despite the different hardness of steel and tin. With this procedure, samples of various types of steel gave correct analytical results upon sparking except for tin, provided that their diameter was at least 6 mm. The method is fast, cheap and more versatile than alternative ones.

Sliding spark spectroscopy - rapid survey analysis of flame retardants and other additives in polymers

A sliding spark spectrometer with a new powerful excitation source was used to detect halogens, flame retardants and metals in non-chlorine containing polymers. The sliding spark source generated discharges using up to 2 kJ of stored energy. The new generator results in improved signal-to-background ratios (SBR) by the factor of three. With this source and a newly developed low cost charge-coupled device spectrometer it was possible to detect elements simultaneously in polymer materials within 5 s. Fillers and white pigments containing Pb, Ti, Zn, Si, Mg, Ca and Ba were qualitatively detected in polyethylene and polypropylene. Acrylnitrile-butadiene-styrene copolymer samples containing different types of flame retardants were analysed and Cl, Br, P, Sb, Al, Mg and Zn were detected. Limits of detection of about 0.1% w/w for elements in chlorine-free polymers were obtained. The use of multiple linear regression gave better results than the use of one individual spectral line.

Sliding spark spectroscopy ? a new excitation source for generating atomic emission spectra for analysis

In this paper a newly developed technique, the so-called “Sliding Spark Spectrometry” is described. The method, with a comparatively simple system, allows direct in-situ analysis of handy, compact non-conductive material without prior sample preparation. A new excitation source for optical emission spectroscopy has been developed. The basic principle of the method is the thermal vaporization, ionization and excitation of a small amount of surface substrate using a train of high-current sliding sparks. The material components in the spark plasma are activated to emit radiation. From the atomic spectrum, informations about the composition and the element concentration in the sample can be obtained. With the use of the sliding spark spectrometer, a rapid analysis, especially of chlorine containing waste plastics and their inorganic additives can be carried out.

ϑ(1700) and ξ(2230) resonances in the π−p→K s0K s0n reaction at momentum 40 GeV/ c

The reaction π −p→K s 0K s 0n was studied at the incident momentum 40 GeV/ c making use of the 6 m magnetic spark spectrometer MSS ITEP. Partial wave analysis was carried out using ∼ 6700 events of this reaction with t′<0.2 (GeV/ c) 2. In D 0 wave ( J PC =2 ++) we find three states besides the well-known resonances f(1270) and f′(1525): ϑ(1700) with the width 30 MeV, f″(1980) with the width 145 MeV (very likely a radial excitation of the f′(1525) meson) and ξ(2230) with the width 80 MeV. The measured width of the ϑ-meson is somewhat smaller, and that of the ξ-meson is somewhat higher than the known values from J ψ radiative decays. In S wave ( J PC =0 ++) we find the known states ϵ′(1440) and S ∗(1720). Using the same data we studied the reaction K − p→ K s 0 K s 0 Y ∗ , where f′(1525) was observed with very small background. No higher mass states were observed with appropriate statistical confidence. In particular, σ(ϑ(1700))× Br(ϑ → K K σ(f′(1520)) ⩽ 0.05 (90% c.l.) , which implies that ϑ cannot be interpreted as an s s state.

Automatic analysis of a huge amount of pictures related to a spark chamber experiment of the Milano-Dubna collaboration

During 1974–1977 the collaboration has collected more than 900 k events at the Serpukov accelerator using a phototaking system with a 5 m long magnetic spark spectrometer. The aim of the experiment is the study of the diffraction dissociation of π and K mesons on different nuclei at 40 GeV/ c. The major part of the events (that is 750 k events) has been processed at CNAF during 1977–1979. As the events were recorded in two views, we handled more than 1.5 × 10 6 pictures. The aim of the automatic system was the accurate measurements of spark coordinates, that were then analyzed by an off-line pattern recognition program. To guarantee a homogeneous quality of information to the pattern recognition program, we introduced suitable controls to check for good computation of fiducials and spark centres of gravity, together with distortion correction.

NEW IMPROVED SPARK SPECTROMETER

School Science and MathematicsVolume 80, Issue 3 p. 226-226 NEW IMPROVED SPARK SPECTROMETER First published: March 1980 https://doi.org/10.1111/j.1949-8594.1980.tb09620.xCitations: 1AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article.Citing Literature Volume80, Issue3March 1980Pages 226-226 RelatedInformation

Study of particle beams with energies up to 70 GeV using a spark spectrometer

Study of particle beams with energies up to 70 GeV using a spark spectrometer