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Carbon Steel (carbon + steel)
Kinds of Carbon Steel Selected AbstractsEvaluation of Transient Liquid Phase Bonding Between Titanium and SteelADVANCED ENGINEERING MATERIALS, Issue 7 2009Ahmed Elrefaey An investigation of microstructural development in transient liquid phase (TLP) bonds between commercially pure titanium and low carbon steel is presented in this study. Changes in the joint region and surrounding substrates were examined as a function of holding time at temperatures of 870 and 910 °C. Both interfacial microstructures and mechanical properties of brazed joints were investigated to evaluate joint quality. [source] Effect of test frequency on fatigue strength of low carbon steelFATIGUE & FRACTURE OF ENGINEERING MATERIALS AND STRUCTURES, Issue 6 2009N. TSUTSUMI ABSTRACT Ultrasonic fatigue tests (test frequency: 20 kHz) and conventional tension,compression fatigue tests (10 Hz) have been conducted on annealed and 10% pre-strained specimens of 0.13% carbon steel. Small holes were introduced on the specimen surface to investigate the effect of test frequency on small crack growth. The dynamic stress concentration factor and the stress intensity factor under ultrasonic fatigue tests were checked to be almost the same as those of conventional tension,compression fatigue tests. However, the fatigue properties were dependent on the test frequency. Ultrasonic fatigue tests showed longer fatigue life and lower fatigue crack growth rate for the annealed and 10% pre-strained specimens. Slip bands were scarce in the neighbourhood of cracks under ultrasonic fatigue tests, while many slip bands were observed in a wide area around the crack under conventional fatigue tests. In order to explain the effect of test frequency on fatigue strength, dynamic compression tests with Split Hopkinson bars were carried out. The stress level increases substantially with the strain rate. Thus, the increase in fatigue strength might be, to a large extent, due to a reduction in crack tip cyclic plasticity during ultrasonic fatigue tests. [source] Cavitation peening to improve the fatigue strength of nitrocarburized steelFATIGUE & FRACTURE OF ENGINEERING MATERIALS AND STRUCTURES, Issue 10 2008S. FUKUDA ABSTRACT Shot peening is a commonly employed technique used to improve the fatigue strength of nitrocarburized components. However, the compound layer of the component can be broken by this technique. Cavitation peening (CP) is an alternative shotless technique, which can increase the fatigue strength of the component without separation of the compound layer. To evaluate the potential of CP as a means for improving fatigue strength, nitrocarburized carbon steel (JIS S50C) has been analyzed in the non-peened and CP conditions. The fatigue strength of CP specimens was increased by 15% in comparison with that of non-peened specimens. This increase in the fatigue strength of CP specimen was achieved by the increase in the maximum hardness and compressive residual stress within the diffusion zone. [source] Microstructures and adiabatic shear bands formed by ballistic impact in steels and tungsten alloyFATIGUE & FRACTURE OF ENGINEERING MATERIALS AND STRUCTURES, Issue 12 2003Z. Q. DUAN ABSTRACT Projectiles of sintered tungsten alloy were fired directly at two kinds of steel target plates. The microstructures near the perforation of a medium, 0.45% carbon steel target plate can be identified along the radial direction as: melted and rapidly solidified layer, recrystallized fine-grained layer, deformed fine-grained layer, deformed layer and normal matrix. The adiabatic shear bands cannot be found in this intermediate strength steel. The microstructures along the radial direction of perforation of 30CrMnMo steel target plate are different from that of the medium carbon steel. There was a melted and rapidly solidified layer on the surface of the perforation, underneath there was a diffusing layer, and then fine-grained layer appeared as streamlines. Several kinds of adiabatic shear bands were found in this higher strength steel; they had different directions and widths, which were relative to the shock waves, as well as the complex deformation process of penetration. The deformation of the projectiles was rather different when they impacted on target plates of medium carbon steel and 30CrMnMo steel. The projectile that impacted on the medium carbon steel target plate was tamped and its energy dissipated slowly, while that which impacted on the 30CrMnMo steel target plate was sheared and the energy dissipated quickly. [source] Characteristics of transient heat transfer during quenching of a vertical hot surface with a falling liquid filmHEAT TRANSFER - ASIAN RESEARCH (FORMERLY HEAT TRANSFER-JAPANESE RESEARCH), Issue 6 2007Hiroaki Matsueda Abstract An experimental study has been conducted to elucidate characteristics of transient heat transfer during quenching of a vertical hot surface with a falling liquid film. The experiment was done at atmospheric pressure for the following conditions: an initial surface temperature from 200 to 400°C, a subcooling of 20, 80 K, average velocity of 0.52, 1.24 m/s, and the block material is copper and carbon steel. The surface temperature and heat flux are estimated from the measured temperatures in the block during the quench by a two-dimensional inverse solution. It follows that as the position of wetting advances downward, the position at which the heat flux becomes a maximum also advances downward. The time at which the position of maximum heat flux begins to move is one of the most important parameters and can be predicted by a proposed correlation. In addition, it is revealed that the maximum heat flux for copper depends on the length to which it occurs from the leading edge. © 2007 Wiley Periodicals, Inc. Heat Trans Asian Res, 36(6): 345, 360, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/htj.20167 [source] Abrasive Wear of DLC/PVD Multilayer Coatings: AFM StudiesLUBRICATION SCIENCE, Issue 3 2004C. Martini Abstract The tribological behaviour of multilayered coatings deposited on plain carbon steel was investigated by microscale abrasion tests (MSATs). The multilayered coatings consisted of an outer diamond-like carbon (DLC) layer, a physical vapour deposition (PVD) nitride-based interlayer, and an inner electroless Ni-P layer. PVD TiN- and Ti(C,N)-coated samples with and without the DLC outer layer were studied in order to evaluate the influence of each layer on the tribological behaviour of the multilayer-coated system. The MSATs were carried out using a device based on ball-cratering geometry: a hard steel sphere was rotated against the coated specimen in the presence of an aqueous suspension of SiC particles. The wear coefficients of the multilayers were calculated from the diameter of the wear craters. The morphology of the wear scars produced by the MSATs was studied by atomic force microscopy (AFM). The wear damage was described by measuring the r.m.s. roughness (Sq) on the sides of the wear craters. Roughness values were related to the wear coefficients (kc) for the different multilayers on the basis of mathematical elaboration typical of the ,design of experiment' (DOE) statistical technique. The presence of the DLC outer layer reduced the roughness of the crater sides and significantly increased the wear resistance of the multilayer only in the case of the PVD TiN sublayer. [source] Evaluation of corrosion inhibitors for cooling water systems operating at high concentration cyclesMATERIALS AND CORROSION/WERKSTOFFE UND KORROSION, Issue 5 2009E. A. de Souza Abstract The present work aimed at evaluating AISI 1020 carbon steel corrosion resistance of a 6:4:1:1 (MoO/HEDP/PO/Zn2+) inhibitor mixture present in a solution which simulates an industrial cooling water system operating at high concentration cycles (1050 ppm Cl, and 450 ppm Ca2+). High concentration cycles are desirable, because system purge and treated water consumption are decreased. On the other hand, a high number of concentration cycles can increase the concentration of salts and dissolved impurities, causing corrosion, incrustations, and deposits inside the pipes, heat exchangers, and cooling towers. Thus, the chloride (Cl,) and calcium (Ca2+) ions aggressiveness was studied on the proposed inhibiting mixture, at the temperatures of 40 and 60,°C, through electrochemical techniques like open circuit potential measurements, anodic and cathodic polarization, and weight loss. The results showed that the inhibitor mixture conferred adequate protection to carbon steel in low concentrations, even in high aggressive media. [source] On-line corrosion and corrosion-wear monitoring using a modified electrochemical noise techniqueMATERIALS AND CORROSION/WERKSTOFFE UND KORROSION, Issue 6 2005P.-Q. Wu Abstract In this study, a modified electrochemical noise (EN) technique was used to monitor uniform corrosion and pitting corrosion. In the EN technique, one working electrode is coupled to a microelectrode (e.g. Pt) through a zero resistance ammeter to sense current noise. Results show that the EN technique with a properly selected microelectrode appears to be able to distinguish different corrosion processes like uniform corrosion on mild carbon steel and pitting corrosion on stainless steel. Furthermore, this EN technique was successfully implemented in on-line corrosion-wear monitoring of stainless steel. In addition, the modified EN technique can sensitively detect the interface of nitrogen ion implanted layer and the stainless steel substrate, thus determining the thickness of the implanted layer. [source] Synergistic or additive corrosion inhibition of mild steel by a mixture of HEDP and metasilicate at pH 7 and 11MATERIALS AND CORROSION/WERKSTOFFE UND KORROSION, Issue 11 2004D. Mohammedi Abstract Electrochemical measurements (steady-state current-voltage curves and AC impedance) were coupled with mass-loss measurements, SEM examinations, and EDSX analyses to investigate the inhibition of corrosion of a carbon steel by a mixture of phosphonic acid HEDP (acid 1, hydroxyethylene, 1-1 diphosphonic) and sodium metasilicate pentahydrate Na2SiO3. 5H2O in an industrial hard water containing 3.10,3 M Ca2+ ions. At pH 7, HEDP and Ca2+ act in a synergistic manner, by formation of a HEDP and calcium containing layer. Addition of silicate at this pH value, allows to reach an efficiency of 94% due to an additive inhibition effect. At pH 11, metasilicate, HEDP, and Ca2+ ions reinforce the passive layer in a synergistic way. The mixture (1.7 · 10,5 M HEDP + 2.6 · 10 -3 M SiO2,3) in the Ca2+ containing electrolyte is shown to be able to inhibit efficaciously the corrosion of iron at room temperature, considering uniform corrosion at pH 7 or pitting corrosion at pH 11. [source] Spatially resolved defect studies on fatigued carbon steelPHYSICA STATUS SOLIDI (C) - CURRENT TOPICS IN SOLID STATE PHYSICS, Issue 10 2007P. Eich Abstract Several samples of the common ferritic tool steel AISI 1045 were fatigued in cyclic load tests. The local distribution of the Von-Mieses stress ,VM was simulated using the finite elements method (FEM). In the regions of interest, where ,VM reaches maximum values, the defect distribution was measured spatially resolved by Doppler-spectroscopy (DBAR) employing the Bonn Positron Microprobe (BPM). The lateral distribution of the S-parameter, which could be described by a simple model derived from linear fracture mechanics, corresponds well with the simulated Von-Mieses stress. (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Corrosion inhibition of carbon steel under two-phase flow (water-petroleum) simulated by turbulently agitated systemTHE CANADIAN JOURNAL OF CHEMICAL ENGINEERING, Issue 2 2008Qasim J. M. Slaiman Abstract The corrosion of carbon steel in single-phase (water with 0.1N NaCl) and two immiscible phases (kerosene-water) using turbulently agitated system was investigated. The experiments were carried out for Reynolds number (Re) range of 38 000 to 95 000 using circular disc turbine agitator at 40°C. In two-phase system, test runs were carried out in aqueous phase (water) concentrations of 1% vol, 5% vol, 8% vol, and 16.4% vol mixed with kerosene at various Re. The effect of Re, percent of dispersed phase, dispersed droplet diameter, and number of droplets per unit volume on the corrosion rate were investigated and discussed. Test runs were carried out using two types of inhibitors: sodium nitrite of concentrations 20, 40, and 60 ppm and sodium hexapolyphosphate of concentrations 485, 970, and 1940 ppm in a solution containing 8% vol aqueous phase (water) mixed with kerosene (continuous phase) at 40°C for the whole range of Re. It was found that increasing Re increased the corrosion rate and the presence of water enhanced the corrosion rate by increasing the solution electrical conductivity. For two-phase solution containing 8% vol and 16% vol of water, the corrosion rate was higher than single phase (100% vol water). The main parameters that play the major role in determining the corrosion rate in two phases were concentration of oxygen, solution electrical conductivity, and the interfacial area between the two phases (dispersed and continuous). Sodium nitrite and sodium hexapolyphosphate were found to be efficient inhibitors in two-phase solution for the investigated range of Re. On a étudié la corrosion de l'acier au carbone dans des conditions monophasiques (eau avec 0,1N de NaCl) et diphasiques immiscibles (kérosène-eau) à l'aide d'un système agité turbulent. Les expériences ont été menées pour une gamme de nombre de Reynolds (Re) de 38000 à 95000, avec un agitateur de type Rushton à 40°C. Des tests pour le système diphasique ont été effectuées dans des concentrations de phase aqueuse (eau) de 1%, 5%, 8% et 16,4% en volume, mélangée à du kérosène pour différentes valeurs de Re. L'effet du nombre de Reynolds (Re), le pourcentage de la phase dispersée, le diamètre des gouttelettes dispersées et le nombre de gouttelettes par unité de volume sur le taux de corrosion a été étudié et analysé. Les essais ont été réalisés avec deux types d'inhibiteurs: du nitrite de sodium à des concentrations de 20, 40 et 60 ppm et de l'hexapolyphosphate de sodium à des concentrations de 485, 970 et 1940 ppm dans une solution contenant 8% en volume de phase aqueuse (eau) mélangée à du kérosène (phase aqueuse) à 40°C pour la gamme complète de Re. On a trouvé que l'augmentation du Re augmentait le taux de corrosion et que la présence d'eau améliorait le taux de corrosion en augmentant la conductivité électrique des solutions. Pour la solution diphasique contenant 8% et 16% en volume d'eau, le taux de corrosion est plus grand qu'en monophasique (100% en volume d'eau). Les principaux paramètres qui jouent un rôle majeur dans la détermination du taux de corrosion dans la solution diphasique sont la concentration d'oxygène, la conductivité électrique de la solution et l'aire interfaciale entre les deux phases (dispersée et continue). On a trouvé que le nitrite de sodium et l'hexapolyphosphate étaient des inhibiteurs efficaces dans la solution diphasique pour la gamme de Re étudié. [source] Effect of precipitate size and dispersion on recrystallization behavior in Ti-added ultra low carbon steelsJOURNAL OF APPLIED CRYSTALLOGRAPHY, Issue 3-1 2003E. J. Shin The effect of coiling temperature on precipitates and solid solution was investigated in P-free and P-added Ti-stabilized ultra low carbon steels. The volume fractions of the fine precipitates smaller than 60 nm were evaluated by using small-angle neutron scattering technique. The solute P was quantified from the lattice parameters obtained from neutron diffraction patterns. In the P-free steels, TiC and Ti4C2S2 with various sizes ranging from 5~60 nm were observed. In addition to these precipitates, FeTiP precipitates of a size exceeding 50 nm were also observed in the P-added steel. The amount of fine precipitates smaller than 10 nm and the concentration of solute P was higher in the samples coiled at low temperature. The recrystallization temperature increases if the coiling temperature decreases in both, P-free and P-added steels. The recrystallization temperature of P-free steels is lower than that of P-added steels. In the P-free steels, the pinning effect of fine precipitates played a key role for the retardation of the recrystallization. In the P-added steels, the retardation of recrystallization is due to both, the pinning effect of fine precipitates and the solute drag effect of P in solid solution. [source] Electrical Resistivity and Phase Transformation in SteelsMATERIALWISSENSCHAFT UND WERKSTOFFTECHNIK, Issue 1 2003O. N. Mohanty Elektrischer Widerstand; Phasenumwandlung; Magnetische Eigenschaften Abstract Changes in electrical resistance accompanying transformations in steels with magnetic change (e.g. , , martensite/bainite) and without magnetic change (e.g. , , ,, above Curie temperature) have been examined; the former class affects the resistivity the latter does not. Next, while the efficacy of electrical resistivity measurement in capturing the well-known features of austenite stabilization (e.g. over , ageing, reversibility, and influence of prior martensite amount and so on) in high carbon steels has been reported in an earlier publication, new features (e.g. increase in resistance -increase at very low temperatures, change in temperature co-efficient of resistivity in the stabilized material etc.) are highlighted here. Finally, the work shows that a quantitative estimate of precipitation in the copper bearing, age-hardenable HSLA-100 steel during tempering can be done by continuous electrical resistivity measurement. These data also allow an in-depth kinetic analysis using the Johnson-Mehl-Avrami equation. Zusammenhang zwischen elektrischem Widerstand und Phasenumwandlungen in Stählen Änderungen des elektrischen Widerstands wurden im Zusammenhang mit Phasenumwandlungen, die zu Änderungen der magnetischen Eigenschaften führen (z.B. , , Martensit/Bainit), und solchen, die keine Änderungen der magnetischen Eigenschaften bewirken (z.B. , , , oberhalb der Curie-Temperatur), untersucht. Während sich die erste Umwandlungsart auswirkt, gilt dies für die andere nicht. Während über die Empfindlichkeit von Widerstandsmessungen zur Erfassung der Austenitstabilisierung (z.B. Überalterung, Umkehrbarkeit, Einfluß des vorher vorhandenen Martensitanteils, usw.) in übereutektoiden Stählen in einer früheren Veröffentlichung berichtet wurde, wird im zweiten Teil der hier vorgelegten Veröffentlichung auf neuerdings erfassbare Merkmale (z.B. der Anstieg des Widerstands bei sehr niedrigen Temperaturen, die Änderung der Temperaturabhängigkeit des Widerstands im stabilisierten Material, usw.) eingegangen. Schließlich zeigt die Arbeit, daß durch kontinuierliche Widerstandsmessungen während des Anlassens eine quantitative Abschätzung der Ausscheidungsgehalte im kupferhaltigen, ausscheidungsverfestigenden HSLA-100-Stahl erfolgen kann. Die Daten hierzu erlauben zudem eine vertiefte kinetische Analyse auf Basis der Johnson-Mehl-Avrami-Gleichung. [source] | ||||||||||||||||